The Element – Summer 2021

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ELEMENT GODOLPHIN & LATYMER

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SUMMER 2021

ISSUE 2

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Welcome Welcome to the second edition of The Element, Godolphin’s chemistry magazine.

This magazine was created by a group of the LVI with the aim of collating articles from a variety of areas within chemistry, which we hope you will find fascinating and informative.

In this issue we have articles ranging from sustainable fashion to explosive chemistry and inspirational women in STEM. You will also be able to get some great book reviews from our very own chemistry department, which is great for wider reading if you want to study chemistry later, or are just enthusiastic like us!

We hope you enjoy reading the articles!

Tabitha and Rojin Editors

Tabitha Iliffe Rojin Zahaki

Writers

Nadia Baghai Jacqueline Byun Roxanna Fahid Clara Gilardi Jess Gilbert Hannah Goldin Alice Grossman Freya Gubbay Tabitha Iliffe Angelina Kim Aya Kodmani Ella McKean Lara Weeks Rojin Zahaki

Cover by

Jess Gilbert

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Contents Chemistry in warfare The atomic bomb of Hiroshima and Nagasaki

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Herbicidal warfare: the chemistry of the Vietnam War

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Chemistry in medicine Cocaine- poison or medicine?

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Chemistry on anti-aging

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PET scans and antimatter

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The chemistry of cocaine

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The chemistry behind the placebo effect

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The chemistry of autopsy

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Sustainability spotlight How MOFs are being, and could be, used to combat climate change 28 Can sustainable fashion start from food waste?

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Should we be reconsidering our lockdown athleisure wear?

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New frontiers The future of nanotechnology

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Atom thick graphene: the new super material

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Women in STEM Marie Maynard Daly

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Editors’ picks

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Teachers’ picks

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The Atomic Bomb of Hiroshima and Nagasaki Atomic bombs are nuclear weapons that use nuclear fission to create explosions. The difference between a nuclear bomb and a hydrogen bomb is that nuclear bombs use fission whereas hydrogen bombs use fission and fusion to power the explosion.

Fission is the process of splitting a nucleus in an atom into smaller particles. They were often used by the US in the course of warfare, particularly during WWII. The most prominent uses of the atomic bomb were “little boy” in the US attack on Hiroshima and “fat man” in the US attack on Nagasaki. The bombings created huge destruction on the japanese people - most of them being civilians.

Common types of atomic bombs, or at least the two that were used during the second world war, use the isotope uranium 235 or plutonium 239. The isotope uranium 235 is used because of its ability to sustain a fission nuclear chain reaction. The free neutron is released and when it hits the nucleus of uranium, the uranium is forced to split into two smaller atoms. However, in order to detonate the bomb, you need to have enough U-235 to ensure that neutrons released by the fission will allow for it to strike through another nucleus, hence the chain reaction. If the material is more fissionable, the chances of creating a reaction is greater due to the greater chance of the nucleus being hit.

The destructive power that is derived from an atomic bomb is due to the sudden release of energy that is produced from splitting the nucleus of a fissile element in the bomb core. The Americans developed two types of atomic bombs: “little boy” and “fat man”. Whilst both are used as atomic bombs and require similar processes to be detonated, ‘little boy” is powered

by Uranium-235 and “fat man” is powered by Plutonium-239.

LITTLE BOY

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FAT MAN Little boy is powered by the uranium isotope U-235. Over 99.3% of the world's uranium is the isotope U-238 with only 0.7% being U-235. This made it extremely difficult to find and extract. When a neutron is released and hits a U-238 isotope, the neutron is captured and converted into U-239.

However, it fails in the fission process and hence does not allow for a chain reaction to occur that would’ve allowed for the bomb to detonate. The difficulty in creating an atomic bomb with U-235 is that scientists had to find the most efficient way to separate the U-235 from the U-238 and then be able to purify it. Standard ways of separation were proved to be difficult to use because of their strong chemical similarities. Eventually, scientists found 4 different ways they could separate and purify U-235: gaseous diffusion, centrifuge, electromagnetic separation and liquid thermal diffusion.

When enough U-235 was gathered to be able to detonate the bomb, Little boy was constructed using a gun style design that allowed for one mole of U-235 to be fired at another and combine masses. The combining of masses created a set mass that was able to set off a fission chain reaction and eventually detonate the bomb. If the two moles didn’t combine fast enough, they could not avoid the spontaneous fission of the atoms and caused the bomb fizzle thus failing to explode.

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Fat man is powered by the plutonium isotope Pu-239. The difference between Fat man and Little boy is that Fat man couldn’t have used the same gun type design due to the form of plutonium being collected from the nuclear reactors. The plutonium that initially was extracted was less pure than the Uranium. The isotope of Plutonium-240 high fission rate would’ve caused the atoms to undergo a spontaneous fission reaction before the gun style allowed for the two Plutonium masses to merge together.

This would’ve lowered the energy involved in the actual detonation of the bomb. Hence, a new design had to be created in order for the fission of Plutonium to be successful and detonate with enough aggression. A design was created to work around the central Plutonium mass. It would quickly squeeze and consolidate the plutonium which allowed for an increase in pressure and density of the substance. If density increased, this allowed for the plutonium to reach a critical mass that would force it to fire neutrons and allow a fission chain reaction to occur. The only way the bomb would detonate would be if it was ignited releasing a shock wave

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compressing the inner plutonium and causing its explosion.

By Jacqueline Byun References and further reading: https://www.atomicheritage.org/history/ science-behind-atom-bomb

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Herbicidal Warfare: The Chemistry of the Vietnam War T h e Vi e t n a m Wa r w a s l a r g e l y characterised by chemical warfare by the US forces, particularly the use of Agent Orange. Agent Orange, which was discontinued in the 1970s, was one of the US tactical-use Rainbow Herbicides, named according to the colour of the barrels they were stored in. It was used to strip forests of their leaves in order to reveal concealed members of the Vietcong and to deprive the Vietcong of crops needed for food, traps and weapons.

Before we can begin to understand the effects of Agent Orange, we must first understand its composition. The active ingredient in Agent Orange is an equal mixture of two phenoxy-herbicides, 2,4-dichlorophenoxyacetic acid (2,4-D) and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T), both of which are common but powerful defoliants. Both work by mimicking the plant growth hormone group, auxin. They are absorbed by plants and translocated to the meristems in the roots and shoots and there, they cause uncontrolled, unsustainable growth which causes the stems to curl over, leading to the death of the plant. Both also specifically target broadleaf plants.

The main issue with this synthetic auxin cocktail is that in their iso-octyl ester form (the specific isotope used in Agent Orange), they contain trace 8

amounts of a dioxin, which are persistent environmental pollutants, or POPs for short. The dioxin found in Agent Orange was 2,3,7,8tetrachlorodibenzo-p-dioxin (TCDD), which even in the tiny amounts p r e s e n t , w a s a s i g n i fi c a n t contaminant.

A molecule of TCDD TCDD is one of the most harmful dioxins and is believed to be a human carcinogen. Dioxins readily enter the body by ingestion or physical contact and they do this by binding to a protein called the aryl hydrocarbon receptor (AhR), which is a transcription factor.

When the protein moves to the nucleus of a cell, TCDD affects gene expression. It’s also fat-soluble, so it can be stored in the body for long periods of time before it ever enters the bloodstream. TCDD’s half-life in the human body is 11-15 years, and in the environment it can have a half-life of 1-100 years, depending on where it lands. This presented as a major issue during the Vietnam War, given that it meant that it existed in the water supplies and in crops grown in the affected areas for years to come, harming generations of people who had not even been directly exposed to Agent Orange when it was first deployed. Dioxins bioaccumulate, meaning that due to their long half-life

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in the environment, they can be passed through the ecosystem and build up in different organisms due to processes such as eating and drinking. For example, if a fish absorbs TCDD from the body of water it lives in and a human eats four fish just like it, then the human will have accumulated four times as much of TCDD. This, paired with the health risks of TCDD, means that the implications of the use of Agent Orange, especially to the massive extent during the Vietnam War, are much wider for a much greater population than originally perceived. After its use in the Vietnam War, Agent Orange was identified as the cause of reproductive problems, developmental issues, hormonal interferences and birth defects in multiple generations. Furthermore, the populations living off the land that was defoliated suffered from devastating famine due to the vast areas of land that were rendered almost completely agriculturally redundant for several years.

Sweden have suggested a link between exposure to herbicides and sarcoma. For now, it has been concluded that there is enough experimental evidence for TCDD’s carcinogenicity and that a small proportion of human malignant tumours may be due to exposure.

Due to dioxins’ omnipresence in the environment (not just because of the Vietnam War), there is a constant background exposure and a certain level in the body, although this varies from person to person depending on diet and geographical location. This leads to something called “body burden”, which is the accumulation of synthetic materials that are stored in the human body at detectable levels.

Current normal background exposure is not enough to be harmful on average, although due to the high toxic potential of dioxins, it is vital that more research be conducted in order to learn more about the effects of bioaccumulation.

By Roxanna Fahid

There has been an ongoing debate as to whether post-Vietnam cancers can be attributed to exposure to TCDD. It was classed as a “known human carcinogen” by the WHO’s International Agency for Research on Cancer but, as far as scientists know, it does not alter genetic material as a normal carcinogen would. While it alters gene expression, it never changes an organism’s sequence of nitrogenous bases, which would cause uncontrolled growth, leading to tumour formation. Several studies from 9

References and further reading: h t t p s : / / w w w. a s p e n i n s t i t u t e . o r g / programs/agent-orange-in-vietnamprogram/what-is-agent-orange/ https://www.britannica.com/science/ Agent-Orange

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https://www.history.com/news/agentorange-wasnt-the-only-deadlyc h e m i c a l - u s e d - i n vietnam#:~:text=In%201961%2C%20t est%20runs%20began,looked%20like %20that%20to%20Pilsch.) https://en.wikipedia.org/wiki/ Agent_Orange http://npic.orst.edu/factsheets/ 24Dgen.html https://study.com/academy/lesson/ what-is-bioaccumulation-definitioncauses-examples.html https://www.medicalnewstoday.com/ articles/17685#health-risks https://www.who.int/news-room/factsheets/detail/dioxins-and-their-effectso n h u m a n health#:~:text=Dioxins%20are%20hig hly%20toxic%20and,hormones%20an d%20also%20cause%20cancer. https://ehp.niehs.nih.gov/doi/10.1289/ ehp.8562329

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Cocaine- Poison or medicine? Chemistry behind the dangerously addictive drug.

Cocaine, or chemically named as benzoylmethylecgonine (C17H21NO4), is categorised as a tropane alkaloid extracted from the coca leaves- found most abundantly in South America. It is thought that native Peruvian tribes in the Andes would chew on the plant to increase their heart rate and help them cope in the low oxygen-high altitude atmosphere they would experience in the mountains.

However, cocaine only became popularised medically in the 1880’s when chemists advertised its “magical” benefits for curing depression and increasing happiness. Even psychoanalyst Sigmun Freud was a regular user of the drug and readily promoted the “beneficial” impacts of it.

Its popularity continued through the 19th century and was further highlighted when the drinks company “Coca-cola” even added it to their sodas and advertised the drink as a ‘euphoric energy booster.’ It wasn't until 1922 that the United States banned the use of the drug as the number of cocaine-related deaths skyrocketed. Undeniably, the effects of cocaine when used recreationally are destructive, however, the question still remains- could cocaine be useful in medicine?

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Within the human brain, there is a structure of neurons which are all connected forming the “reward circuit.”

When someone experiences something pleasurable, such as eating food or winning a race, the brain releases the hormone dopamine from one neuron to dopamine receptors on the surface of another neuron through a synaptic gap (the space between two neurons.) This triggers the protein receptors to stimulate a response which continues the circuit. Then, the dopamine molecules are released back into the original neuron to be reused again. Ultimately, this causes the feeling of happiness and causes the body to want to repeat the action.

However, when someone ingests cocaine and dopamine is released, the cocaine molecules block the neurons releasing the hormone, causing a build up of dopamine to accumulate in the synapse (as the recycling process is blocked.) As a result, the receiving neuron thinks the person is continuously being exposed to this pleasing activity and continues stimulating the “happy” response.

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In the short term, this causes that ‘euphoric’ feeling of energy and pleasure. In the long term, it causes increased depression as natural things such as food no longer stimulates the release of dopamine. Instead, users become addicted to the drug and it becomes, quite literally, their only source of pleasure. The withdrawal from the drug stimulates the stress circuit to become over-sensitive leading to anxiety when not taking the drug, worsened moods, increased frustration and irritability. Elsewhere in the body, cocaine also has detrimental impacts. It reduces blood flow through the gastrointestinal tract causing holes and tears to occur in the stomach and intestines. Numerous reports have demonstrated that cocaine significantly affects the cardiovascular system- causing increased heart attacks and strokes. In the case of overdosing, when a person takes more cocaine than their body can physically handle, the brain becomes overstimulated. This causes a dangerously fast heart rate, high blood pressure and temperature.

Consequently, it can lead to vomiting, seizure and in many cases: death.

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U n d e n i a b l y, the consequences of recreationally using cocaine are deathly. But, interestingly enough, its uses in medicine are prevalent. The main use of the drug in hospitals is as an anaesthetic. It’s ability to block nerve ends and prevent the transmission of nervous signals makes it ideal to numb, or relax, certain parts of the body (in preparation for a procedure.)

It is also commonly used as a vasoconstricting agent by reducing the amount of natural nitrous oxide in the body- a strong vasodilating agent. This causes the blood vessels to constrict, reducing the volume of blood flowing to body cells.

This is, therefore, useful in procedures as it prevents too much blood from being lost from the body. However, doctors must be wary of using the correct dosage of cocaine for the purposes of vasoconstriction. Too much- cells will die from starvation of oxygen and organs will be damaged.

Interestingly enough, cocaine is the only drug which possesses these abilities making it stand out amongst similarly powerful drugs.

In conclusion, the uses of cocaine have clearly changed a lot ever since the native Peruvians chewed on it for survival. Yet even now, when medicine has developed astronomically, the uses of the drug to save lives are still minute, in comparison to the deadly effects of it when used recreationally.

Consequently, there is no debate that

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cocaine is far more poisonous than it is medicinal.

By Aya Kodmani

h t t p s : / / w w w. d r u g f r e e w o r l d . o r g / drugfacts/cocaine/a-short-history.html https://www.drugabuse.gov/videos/ reward-circuit-how-brain-responds-tococaine h t t p s : / / w w w. d r u g a b u s e . g o v / publications/research-reports/cocaine/ how-does-cocaine-produce-its-effects https://drugabuse.com/drugs/cocaine/ overdose/ https://www.therecoveryvillage.com/ cocaine-addiction/faq/vasoconstriction/ h t t p s : / / w w w. e n t n e t . o r g / c o n t e n t / medical-use-cocaine

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Chemistry on Anti-Aging It is well known that everyone wants to ‘stay young’ forever. There are millions of products out there that claim to supply you with the elixir of eternal youth, however is it even scientifically possible to erase/prevent signs of aging?

To discuss this question let’s start off by looking at anti aging creams: Most anti-aging creams will tend to advertise themselves as reducing the appearance of wrinkles. Now let's dive deeper into what these products contain.

1. Retinoids: The definition of a retinoid is any of a group of compounds having effects in the body like those of vitamin A. They are used to reduce the appearance of wrinkles by increasing the production of collagen which is an insoluble fibrous protein found all over the body, it gives skin its strength and elasticity. Collagen production usually decreases with age leading to wrinkles , so if production is increased then skin will maintain its elasticity and strength decreasing the appearance of aging. Retinoid containing products such as retinol can be purchased in a drugstore but they won’t decrease the signs of ageing as much as tretinoin would and that has to be prescribed by a doctor.

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2. Another Common thing that anti aging products contain are AHAs , these are typically used to exfoliate the top layer of your skin (unclogs and continued use prevents future clogs from forming).

Now how does it work?: AHAs work by slowly breaking down the intracellular ‘glue’ that makes old dead skin cells stick to the epidermis and as a result the outermost layer of your skin will look more smooth and bright.

Below is an example of an AHA:

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3. Other popular ingredients include VItamin C and E. These are antioxidants, they help to prevent damage from the sun. This is vital to prevent aging as Ultraviolet radiation causes DNA changes in the skin that can lead to premature aging and skin cancer!

Formula of Vitamin C :

suggestion that ‘staying young forever’ is possible, aging is natural and shouldn’t be feared or viewed as negative. In my opinion instead of focusing on not aging, you should instead focus on aging gracefully.

By Hannah Goldin References and further reading: https://www.compoundchem.com/ 2017/03/06/anti-aging/ h t t p s : / / w w w. h e a l t h . h a r v a r d . e d u / staying-healthy/do-retinoids-reallyreduce-wrinkles

4. Finally but most importantly we come to sunscreen (UV protection) this is a vital component of few skincare products.

So how does sunscreen work?: It works by blocking and absorbing dangerous UV rays through a combination of physical and chemical particles. Physical particles , such as zinc oxide and titanium dioxide, are usually used as they have the ability to reflect UV radiation from the skin.

It is important to wear sunscreen everyday and remember to reapply as this will prevent the aging effects of the sun!

In conclusion it is possible to prevent and lessen the signs of aging , however this mostly applies to the face and neck region as most skincare products are directed towards those areas. I disagree with the 15

https://www.healthline.com/health/ beauty-skin-care/alpha-hydroxyacid#_noHeaderPrefixedContent https://www.thehealthy.com/beauty/ anti-aging/how-to-use-alpha-hydroxyacids-to-reduce-wrinkles/

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How PET scans utilise antimatter In 1982, Paul Dirac discovered new equations to describe how particles such as electrons behave when travelling close to the speed of light (shown below). However, upon completion, he found that his equation always had two possible solutions, much as the √4 = ∓2. For his equation, one answer described the electron, however one described something with the same mass and spin as the electron but with an opposite charge: an antielectron, also known as a positron. This is a type of antimatter. Dirac's equation proved true not only for just electrons, but also for other kinds of particles: quarks have antiquarks and because quarks make up protons, antiprotons also exist. Similarly, antiprotons and antielectrons can make up antiatoms and so on.

Positrons can be used for medical purposes in positron emission tomography (PET) scans which construct images to check for things such as checking brain function, metastasis, the body's response to a cancer treatment or examining blood flow. PET works by using a scanning machine to detect photons emitted by a radioisotope, an atom with excess nuclear energy, in the organ being examined. These radioisotope are

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made by a particle accelerator called a cyclotron through this process: 1.

A negatively charged hydrogen ion is injected into the vaccum chamber of the cyclotron where two D shaped plates are enclosed between the poles of a strong electromagnet 2.

An alternating positive and negative voltage is sent through the D shaped plates which attracts and repels the ion in a circular path.

Each time the ion passed the gap between the D shaped plates, it accelerates as it gains energy

3.

On the outside of the D shaped plates is extraction foil. When the ion reaches the outside and hits this foil, it is stripped of its electrons, leaving a positively charged proton 4.

This proton travels down a beamline towards a target containing atoms. When the proton collides with the nucleus of an atom in the target, a nuclear reaction changes the atoms structure which creates the radioisotope The radioisotope is then added to a molecule that is easily absorbed by the body such as a sugar, hormone or

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protein. Each of these performs a specific function in the body, allowing doctors to see where in the body that function is happening.

Once the biological molecule and radioisotope have been synthesised it is purified and checked it will properly function before being injected into the patient's bloodstream to reach the target organ.

By Alice Grossman

Inside the body, the radioisotope on the newly synthesised molecule emits a positron/ antielectron. Because the positrons and electrons are oppositely charged, when they collide and are both destroyed. Energy is produced in this collision due to the 2 equation 𝐸 = 𝑚𝑐 and released as two gamma rays which travel out of the body in opposite directions. Due to the spherical shape of the PET scanner, when it detects two gamma rays on opposite sides of the ring, it is able to locate exactly where in the body the tracer is. By detecting thousands of these events every second, an image can be produced in 3D of the structure of the target organ.

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References and further reading: https://www.hopkinsmedicine.org/ health/treatment-tests-and-therapies/ positron-emission-to mographypet#:~:text=How%20does%20PET%2 0work%3F,organ%20or%20tissue%20 being %20examined. https://phys.org/news/2006-10antimatter-chemistry.html https:// www.chemistryworld.com/news/ antimatter-persuaded-to-react-withmatter/3000369.ar ticle https:// iopscience.iop.org/journal/1367-2630/ page/ Focus%20on%20Antimatter%20Physi cs% 20and%20Chemistry https://fedorukcentre.ca/resources/ what-is-a-cyclotron.php

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The chemistry of cocaine While we are surrounded by constant conversations about drugs and their dangers, we rarely consider how they have come about and what effect they have on us.

Consider the class A drug cocaine holding second place on the list of the most commonly used illegal drugs in the world. Whilst you may know about its white powder appearance and possibly a little about its effects - do you know what it actually is, or why it even holds that amount of power upon such a large number of humans?

The beauty about chemistry is that it is all around us, and in everything. So, by taking such a commonly known yet confusing concept of illegal drugs and actually learning about the science behind it, we can clear up some misconceptions about it, what it does to you, and how we test for it.

Hopefully, this will make you never want to go near it!

Cocaine, or its IUPAC name: methyl (1R,2R,3S,5S)-3-(benzoyloxy)-8methyl-8-azabicyclo[3.2.1] octane-2carboxylate, is a strong stimulant made from coca leaves from one of the four species of plant in the Erythroxylaceae family. Its chemical formula is C17H21NO4 and it is what is known as a tropane alkaloid. This sounds complicated, but it is just explaining that it belongs to a class of alkaloids and secondary metabolites and has a tropane ring in its chemical 18

structure. To understand this, we need to break it down - alkaloids are naturally occurring organic compounds containing at least one nitrogen atom, secondary metabolites are organic compounds produced by bacteria, fungi or plants that are not used in their normal processes and a tropane ring just refers to the bonding of the compounds! See, not complicated, just unfamiliar.

As you now know, cocaine is actually naturally occurring. So, how was it found? Three thousand years BC, ancient Incas in the Andes chewed coca leaves, because the coca bush grows wild there. The bush makes cocaine from the amino acid Lglutamine as a protection mechanism to stop insect predators from eating it, and studies show that its leaves contain around 0.3-0.7% cocaine. The ancient Incas chewed coca leaves in order to get their hearts racing and to make their breathing faster, getting more oxygen into their bodies, in order to counter the effect of living in the mountains. Nowadays, cocaine users don’t actually chew leaves 'thanks' to the work of a few chemists, starting with Heinrich Wackenroder, who was a German pharmaceutical chemist that was able to produce an extract of the active ingredient in the coca leaves.

He did this by creating a solution with 84% ethanol and 14% water producing a solution that reacted with isinglass (purified gelatin) solution and iron (III) chloride - so we weren’t quite there yet. Two years later, Friedrich Gaedecke was able to evaporate an aqueous extract of the leaves, and

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with its dry residue he obtained white crystals. However, these crystals were coated in an oily residue, so still not there yet, and he named them “Erythroxyla coca”. Finally, Albert Niemann came along and used the ethanol and water mixture with a dash of dilute sulfuric acid at 40 degrees to produce the final product, giving it the name cocaine.

So, now we know about how cocaine was found and synthesised - let's try and understand why so many people are addicted to it and the answer lies i n i t s c h e m i c a l s t r u c t u r e . To understand the difference it makes, we need to understand the normal brain activity to see the contrast, and in order to do this we can look at the neurotransmitter - dopamine.

Neurotransmitters are made by the body and used by the nervous system in order to send messages between nerve cells - they act as a sort of ‘chemical messenger.’ The chemical formula for dopamine is C8H11NO2.

Usually, neurons release dopamine into the synapses (gaps between neurons) where it binds to dopamine receptors (special proteins) on the adjacent neuron. This movement is why dopamine is a chemical messenger, as it is able to carry a signal from one neuron to the other.

Once this movement happens, the dopamine can be recycled so another special protein, a transporter, removes the dopamine from the synapse to take it elsewhere. However, this is the process in which cocaine gets involved. Once a person has cocaine

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in their system, it blocks the so-called ‘recycling step’ I previously mentioned.

The chemical structure of cocaine allows it to bind to the transporter as it is on its way to pick up the dopamine, prohibiting it from doing so as the space is taken up. Therefore, the dopamine is stuck in the synapse, meaning that over time, the lack of transporters picking the dopamine up creates a build-up of dopamine in the synapse, essentially amplifying the signal to the receiving neurons. This a m p l i fi e d s i g n a l r e s u l t s i n t h e ‘euphoric’ feeling users get when they take the drug. This process is a reason why cocaine is known as a SNDRI, a serotonin–norepinephrine– dopamine reuptake inhibitor.

While cocaine can ruin a user’s life very easily, it can surprisingly also be used in different ways to do good.

While the medicinal use of cocaine has decreased due to the uprising of other local aesthetics, no other drug is able to combine the anaesthetic and vasoconstricting properties in the same way as cocaine. Cocaine is a good anaesthetic because of its ability to block nerve impulses, especially norepinephrine which allows it to be an anaesthetic and a vasoconstricting agent. Cocaine hydrochloride is an ester local anaesthetic and has been approved for use in the United States for adults. Additionally, it can be used in the form of a topical solution as a numbing agent. While these are a few good uses of cocaine to help people, these positive characteristics exist only in medical settings - any cocaine

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distributed elsewhere will always be dangerous.

the two main fragments of the molecular ion.

It is also quite interesting to observe the chemical reactions that take place when the body deals with cocaine, occurring in the liver. This human organ uses carboxylesterase enzymes hCE1 and hCE2 in order to metabolise cocaine and after these processes only 1% of the cocaine leaves our body unchanged. The liver metabolises cocaine by hydrolysis, and the reaction is catalysed by carboxylesterases and excreted in the urine, and this allow us to detect cocaine use because only a mere four hours after the intake of cocaine, the cocaine metabolites for example, benzoylecgonine, are detectable in urine. Furthermore, if cocaine is taken with alcohol (ethanol), the hCE1 enzyme can turn the cocaine into coca ethylene which is an ethyl ester. This is why the combination of both is more toxic than taking cocaine or ethanol separately.

Now you know the history behind cocaine - the effects it has on the body, how harmful it can be, and how we test for it. After all, it's just chemistry!

Finally, due to the way that cocaine is sometimes ‘snorted’ with bank notes, a 2007 study showed that the majority of euro notes had detectable levels of cocaine on them! How did they work this out? They used the technique of mass spectrometry. Essentially, if the note is heated up to 285 degrees for one second, the cocaine molecules are released and carried on a stream of air into the spectrometer. If the spectrometer is looking for cocaine, it is programmed to pick out the peaks with the m/z values of 182 and 105 -

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By Nadia Baghai References and further reading: https://pubchem.ncbi.nlm.nih.gov/ compound/Cocaine

https://sites.duke.edu/thepepproject/ module-1-acids-bases-and-cocaineaddicts/content-background-chemicalcharacteristics-of-cocaine/

https://www.reagent.co.uk/what-iscocaine-made-of/

https://edu.rsc.org/feature/cocaine-ashort-trip-in-time/2020119.article

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The Chemistry Behind the Placebo Effect: One phenomenon within medicine which has always fascinated me is the placebo effect. The placebo effect can be defined as either a psychological or physiological improvement due to treatment of a patient with either an intent substance, such as a sugar pill, or a simulated procedure. Although numerous studies have been conducted on possible explanations for the placebo effect, so far no decisive conclusion has been reached.

It’s more indicative that the effect is caused by the patient's expectation of the treatment, rather than as a direct effect of the drug or procedure.

In modern medicine, a placebo drug is often used as a control in clinical trials.

For example, when trialling the COVID AstraZeneca vaccine recently, some volunteers were unknowingly given placebo vaccines. Most notably, certain antidepressants have failed to provide more benefits than the placebo effect, suggesting how the placebo effect could be more psychological than physical.

Interestingly, the colour, size and price of a pill can also affect patient expectations for effectiveness of the drug. A study in 2008 found that

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participants who took a painkiller sold at a relatively higher price experienced greater pain tolerance when subjected to a mild electric shock.

Ethical issues can surround the use of placebo medications within clinical trials. The researchers know that the medication is fake, but they imply that the treatment is real. This could be considered dishonest, and against the bioethical code of medical practitioners. The declaration of Helsinki has updated their guidelines surrounding placebo use in clinical trials, and states that they can only be used when there isn’t another effective option for a control.

Possible explanations for the placebo effect have a physiological and psychological basis, and are influenced by factors such as expectations and cultural beliefs.

Studies have shown that the release of the neurotransmitter dopamine in the ventral striatum in the brain could influence the placebo effect. Also, patients with chronic illnesses who frequently experience a positive outcome from their treatment, and therefore strongly anticipate

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therapeutic benefit, could be experiencing a form of the placebo effect. This positive expectation from treatment is especially common in patients with Parkinson’s disease, who experienced dopamine release in the basal ganglia in the brain, and this draws the associations between increased dopamine activity and the placebo effect. Parkinson’s disease is unusual in how it is affected by the placebo effect, since the placebo effect usually only impacts levels of pain and nausea, or patient reported outcomes, rather than actual diseases which aren’t dependent on patient perception.

However, it should also be considered whether the placebo effect is actually an unintentional impact of confounding variables. The placebo effect could be due to a response bias from subjects, for example from answers of politeness, or experimental subordination. Moreover, the placebo effect could possibly be due to non inert ingredients inside placebo medications having an unintended effect. However, this is unlikely since placebo medications are usually just sugar pills. Also, since so many studies have been conducted using the placebo effect, it’s unlikely to be 22

completely due to confounding variables only.

As well as positively impacting the treatment of a patient, the placebo effect also has an effect on a number of other physiological systems. These organ systems include the nervous system and digestive system. For example, placebos can decrease the levels of appetite stimulating hormones by convincing the participant they have eaten calorie rich food. Appetite levels are then decreased based on expectation alone. Furthermore, researchers have also found that placebos can affect the immune system. For example, in one study it was found that watching advertisements for the anti allergy drug Claritin led to the drug being more effective than in participants who didn’t receive propaganda promoting the drug.

A more negative aspect to the placebo effect is called the nocebo effect. This is when a patient who receives an inert substance experiences a negative effect or a worsening of symptoms. This is due to negative expectations from the treatment, rather than an outcome from the substance itself. Ethically, this issue has to be considered in clinical trials, due to the number of side effects which can be associated with placebo treatment. Furthermore, withdrawal symptoms can also occur after a placebo treatment. For example, a study by the Women’s Health Initiative study of hormone replacement therapy for menopause found that moderate or

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severe withdrawal symptoms were reported by 4.8% of those on placebo.

I think the placebo effect can have both positive and negative therapeutic effects. This is demonstrated by both the negativity of the nocebo effect and potential for withdrawal symptoms, and the positive association between placebo medication and the relieval of sickness. The placebo effect must be further investigated in order to gain a more conclusive understanding of the neurochemistry behind the effect.

By Lara Weeks References and further reading: https://s4be.cochrane.org/blog/ 2014/08/06/the-placebo-effect/ https://www.britannica.com/science/ placebo-effect https:// www.neuroscientificallychallenged.co m/blog/influence-placebos-brain https://www.ncbi.nlm.nih.gov/pmc/ articles/PMC6013051/

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https://www.health.harvard.edu/ mental-health/the-power-of-theplacebo-effect

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The Chemistry of Autopsy When a person dies, their body cycles through four stages of death. First comes pallor mortis. Within 15-30 minutes of death, capillary circulation collapses and the skin goes pale (an effect most prominent in those with light skin). Pallor mortis is quickly followed by algor mortis during which the body cools to match the temperature of the surroundings and as the body cools, the muscles stiffen and the body grows rigid, a phenomenon known as rigor mortis.

Six to eight hours later, the final stage of death takes hold of the body- livor mortis. A stage characterised by the pooling of the blood to certain areas of the body due to the force of gravity.

These four stages are often quite helpful in determining the time of death, but to gain more insight into how someone has died, autopsies or post-mortem exams are performed. An autopsy involves the examination of the external body, the internal organs and the substances that lie within them.

Let's take a look at this case example: “A 55 year old male is found deceased in a bed in a secure residence . There is an antidepressant medication on scene next to the bed including the tricyclic antidepressant imipramine. In addition, there is a half full bottle of wine on the floor. At autopsy, the medical examiner can find no immediate anatomical cause of death.

The medical examiner submits venous 24

blood, heart blood, vitreous humor and liver to the forensic toxicologist for analysis.”

There are several pieces of important information in this extract, the most prominent of which being the presence of medication and alcohol. This is particularly important as no immediate anatomical cause of death was found by the medical examiner, meaning the cause of death is most likely accessible on a molecular level. The individual’s age and sex will come in useful when interpreting the toxicology results later and as for the submitted specimens, they would be ideally stored between 2-8 degrees celsius to slow distribution and putrefaction (decomposition).

Unfortunately, determining whether the imipramine and/or alcohol was responsible for the death is not as simple as measuring the concentrations of the relevant compounds in the specimens, however several other factors must be taken into account. Most prominently, the phenomenon of post-mortem redistribution (PMR).

Postmortem redistribution involves the changes in drug concentrations after death. Simply put, a drug’s movement around the body from blood to tissue and tissue to blood after death.

The extent to which a drug will display PMR is down to its chemistry. Various drug properties such as volume of distribution, lipophilicity and acid-base

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dissociation are all factors that affect a drug’s post mortem redistribution.

Volume of distribution relates the total amount of drug to the concentration of the drug in the plasma at any given time. Simply put, it’s a proportionality constant represented by the equation below: Volume of Distribution (L) = Amount of drug in the body (mg) / Plasma concentration of drug (mg/L) From this, we can tell that a drug with a high volume of distribution tends to leave the plasma and enter the tissues and those with a low Vd tend to stay in the plasma and thus a drug’s Vd is highly relevant to its overall postmortem redistribution.

PMR is also affected by the drug’s lipophilicity, which is defined as the affinity of a drug for a lipid environment. The greater a drug’s lipophilicity, the faster its redistribution.

The final property that dictates a drug’s likelihood to display PMR is its acid-base dissociation constant (Ka).

In fact, toxicologists are more often concerned with a drug’s pKa, which is the negative log of Ka useful in giving smaller values, which are often more comparable for analysis. Most drugs are weak acids or bases and the smaller the pKa the stronger the basic properties of the drug and conversely the larger the pKa, the stronger the acidic properties of the drug. The pKa of a drug influences its lipophilicity, 25

solubility, ability to bind to proteins and permeability which together impacts its tendency to distribute. All in all, basic, highly lipophilic drugs with a high volume of distribution are most likely to undergo PMR. As you may recall, the antidepressant imipramine was found on the scene.

This drug belongs to a family of tricyclic compounds, named as such due to their characteristic three ring structure. More specifically, imipramine is a dibenzazepine, which refers to its two benzene rings attached to a single azepine group. As for the wine also found in the room, the primary compound in question is ethanol.

Ethanol is not as straightforward a compound as its presence in the body is not all down to the consumption of alcohol. After death, bacteria can metabolise the contents of the body to ethanol altering its concentration meaning determining whether there was excess amounts of alcohol in the body can be quite difficult.

Now let’s say we had two sets of data following the examination of the specimens provided from the initial autopsy.

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The next step is interpreting these results through comparison with reference data. Below are the reference values for the levels of both compounds in a live individual, postmortem levels in a natural death and postmortem levels in death by intoxication fatality.

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In both scenarios, the imipramine has undergone PMR post mortem. We know this by referencing its central to peripheral blood ratio both times. The reference level i.e. the level if it had not redistributed is 1.8. The ratio in scenario one is 3.5 and scenario two is 2.5. Seeing as both of these are higher than the reference level, we can conclude that the drug has undergone PMR- we need to consider this when deciding on the cause of death. With all of this in mind, we can conclude that with the data from scenario one the death was due to an intoxication and with the data from scenario two, the cause of death was likely natural. An interesting conclusion we can draw with scenario two is that we don’t actually know whether or not the wine had been ingested. This is

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because the ethanol present could have been the product of bacteria metabolism.

Overall, chemistry is hugely significant in post-mortem examinations, particularly in forensic toxicology.

Without considering the chemical properties of the compounds within the body, any conclusions we come to would be misinformed.

By Rojin Zahaki References and further reading: https://www.sciencedirect.com/top ics/ pharmacology-toxicology-and-p harmaceutical-science/volume-of-di stribution#:~:text=Volume%20of % 20distribution%20(Vd)%20is,and% 20unbound%20in%20tissue%20wa ter). https://www.ncbi.nlm.nih.gov/book s/ NBK545280/ https://emerypharma.com/blog/dr uglipophilicity-and-absorption-a-co ntinuous-challenge-toward-the-goal -of-drug-discovery/#:~:text=Lipoph ilicity%20is%20defined%20as%20t he, %2C%20pharmacokinetic%2C% 20and%20metabolic%20properties. https://pubmed.ncbi.nlm.nih.gov/1 6035199/ https://journals.sagepub.com/doi/f ull/ 10.1177/1177391X0700100003 https://chem.libretexts.org/Booksh elves/General_Chemistry/Map%3A_ A_Molecular_Approach_(Tro)/16%3 27

A_Acids_and_Bases/16.04%3A_Acid _Strength_and_the_Acid_Dissociatio n_Constant_(Ka)#:~:text=For%20an% 20aqueous%20solution%20of,aK b%3DKw.&text=At%2025%C2%B0 C%2C%20p,%2BpKb%3D14.00. acs.org/content/acs/en/acs-webina rs/ popular-chemistry/death-chemis try.html https://www.scienceabc.com/huma ns/ post-mortemstages-of-death-diff erentstages-the-body-goes-through -afterdeath.html https://www.pathologyoutlines.com / topic/forensicschemistry.html https://link.springer.com/chapter/ 10.1007%2F978-1-59745-127-7_8

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How MOFs are being, and could be, used to combat climate change Metal-Organic Frameworks, or MOFs, are a class of materials which are increasingly being found and used in the world today. They are compounds made up of metal ions and organic molecules (ligands) that form structured frameworks. This gives them the ability to take-up, hold, and release molecules from their pores, similar to sponges. More than 20,000 MOFs have been discovered in the last 20 years, and this number is predicted to grow in the future.

Due to the highly structured framework of pores, MOFs have the largest surface areas per gram of any material.

This gives MOFs enhanced abilities in offering more space for chemical reactions and the adsorption of molecules. Not only is the large surface area responsible for the boom in the growth of MOFs, but the metals and organic ligands which make up the framework can be combined in an almost infinite number of ways to create new materials. This creates a lot of 28

possibilities by changing the functionality of the MOF. Use of MOFs in capturing carbon dioxide Carbon dioxide levels have increased dramatically due to the increased burning o f fossil fuels. One of the most effective ways to combat this issue is to capture and store the carbon dioxide (known as carbon capture, or sequestration). The captured carbon dioxide can then be converted into valuable products, such as chemical fuel (methane) or industrial raw materials (for example, plastic). However, current methods of carbon capture are very expensive, intensive, and they are not able to keep up with the rate at which carbon dioxide is generated.

MOFs are proving to be very effective in capturing carbon dioxide due to the large surface area, their solid state which makes them very easy to handle, the differing pore sizes for selective adsorption of gases from gas mixtures, and the modifiable functional groups for selective adsorption of gases.

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Use of MOFs as a way to store hydrogen In the transport sector, the use of fossil fuels is also a large contributor to climate change, and hydrogen has been proposed as a way to avoid the use of fossil fuels. Hydrogen as a fuel has many benefits, as when it is burned or consumed in a fuel cell to generate electricity, the only emission is water vapour. Unlike fossil fuels which produce NOx, SOx, and CO2 which pollute the air and contribute to climate change, hydrogen as a fuel is clean.

Hydrogen is going to play a big role in the future as a fuel that can be used to satisfy the world’s energy need, however the challenge with hydrogen as a transport fuel is that it is a very light and low-density gas. If a fuel cell car was to use atmospheric pressure to store 1kg of hydrogen (the amount needed to drive 100km), the fuel tank would have to be 11m3. A solution to this storage issue is to use compressed hydrogen gas, squeezing around 5kg into a smaller reinforced tank. However, this also has problems, as a heavy, awkwardly shaped, expensive fuel container has to be used, and a large amount of energy is required to compress the gas.

Adsorbents are structures which provide a surface for atoms, ions or molecules to bind to, and they have the potential to store hydrogen at a lower pressure. MOFs are examples of hydrogen adsorbents. However, even MOFs have some problems, as 29

hydrogen binds too weakly to the porous material for enough of it to be held. This is because hydrogen does not easily ‘stick’ to adsorbents as, in general, to get molecules to stick to the surface, a polarisation effect is used, however, hydrogen only has two electrons, so it is very difficult to polarise. By adding low-coordinate metal cation sites, the MOF will become ‘stickier’, however there is still a lot of research going on in this area, so it is uncertain whether this will provide an effective solution to the hydrogen storage problem.

Other uses of MOFs Not only can MOFs combat the causes of climate change, but they are also increasingly being used to lessen the impacts of climate change. The prevalence of water shortages in hotter areas has risen due to climate change, and MOFs are able to provide a short-term solution to this. Due to the pores in the framework, MOFs can absorb water from the air at night, and during the day they can use solar power to empty the MOF of water.

MOFs are also being used to prevent food waste, as a lot of food is lost between harvest and retail. For example, fruit ripens due to the

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production of ethylene gas, which promotes ripening in other fruits, and 1-MCP (1-methylcyclopropene, a type of MOF) can bind the ethylene and the ethylene action inhibitor, preventing the fruit from ripening.

Carbon dioxide emissions pose the greatest threat to our atmosphere, and MOFs provide a very effective and efficient solution to this problem by being able to selectively adsorb carbon dioxide. Not only do MOFs combat this issue, but they are also increasingly being used to solve other issues related to climate change, such as water shortages, food waste, and the hydrogen fuel storage problem.

By Jess Gilbert References and further reading: https://www.chemistryworld.com/ features/hydrogen-storage-gets-real/ 3010794.article https://blog.novomof.com/blog/howmofs-save-the-climate-from-carbondioxide-and-other-greenhouse-gases https://www.nature.com/articles/ s41467-019-09365-w https://pubs.rsc.org/en/content/ articlelanding/2009/cs/b802256a#! divAbstract h t t p s : / / w w w. s c i e n c e d i r e c t . c o m / science/article/abs/pii/ S004896971935082X

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Can sustainable fashion start from food waste?

Sustainable fashion and some alternatives that have recently been developed in the chemistry research field. With the rise of global warming and threat to the environment, the need to develop or change the sources and exports of human fashion is greatly increased. Sustainability in general is seen as an essential part of the change needed to decrease human effect on the environment.

So what actually is sustainable fashion?

Sustainability itself is being able to maintain and meet the needs of the present without compromising the ability of future generations to meet their needs.

In terms of fashion, being sustainable would focus on sustainable sources of material, shipping methods, packaging and other social and ecological aspects.

For materials to be sustainable they need to tick a certain number of boxes. Namely they must be organic, natural, biodegradable fabrics, use parts of recycled clothing, repurposed materials and use Non-toxic dyes.

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What are some examples of unsustainable fabrics?

Polyester - this is not biodegradable [takes an extremely long time to be broken down naturally by the environment] and when it is being produced it is partially derived from oil.

The oil and gas industry is a major contributor to greenhouse gases that are causing the global temperature to rise significantly each year.

Cotton - it can take more than 20,000 litres of water to produce one cotton tshirt and a pair of jeans. The excess water ends up polluting rivers with the chemicals produced when making cotton clothes.

Leather - although it is a byproduct from another industry, the carbon footprint of this industry is extremely large. The tanning process of leather uses chrome. This produces a lot of toxic waste and serious harm to industrial tannery workers.

What is vegan leather?

Vegan leather is a material that mimics the look and feel of animal leather.

Historically, vegan leather was produced using unsustainable and non-eco friendly PU (polyurethane).

This is a type of plastic which is incredibly damaging to the

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environment because of how long it takes to biodegrade. Just because this leather is vegan doesn’t make it environmentally friendly. In more recent developments, bio-based polymers are being created What are bio-based polymers?

These polymers are materials made with a part organic component.

Although bio-based products are not always biodegradable or compostable, the carbon footprint produced when using these materials would be much less than other polymers that are not bio-based. Many of these products are created from food waste.

Apple leather The core and skin of the apples you ate could be made into a flexible leathery sheet called apple leather.

The apple leather used is made using 50% apple waste (that has been powderised) mixed with 50% Polyurethane

Grape leather This is a 100% recyclable bio-based polymer called grape leather. This is made using grape waste from the wine industry. This was created by a company called VEGEA that received

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the top prize of the global change award.

Pineapple leather Another example is pineapple leather.

It is just as the name says, it is created by taking the long fibres from pineapple leaves. Although it is not biodegradable, it is partially made using a waste product. This means no extra land, water and other resources are used when growing the leaves.

There is also none of the toxic chemicals used in animal leather production.

How does this work?

After pineapple harvest, the plant leaves are collected and the long fibres are extracted using semiautomatic machines.

The fibres are washed and dried. The dry fibres go through a purification process to remove any impurities which results in a fluff-like

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material.The key to creating the pineapple leather is the use of corn based polylactic acid (PLA).

References and further reading: https://www.eco-stylist.com/a-guide-tothe-most-and-least-sustainablefabrics/

Polyurethane vs polylactic acid?

Polyurethane is a ‘thermoset plastic’.

This means that it hardens as it is heated, making it hard to recycle.

Polyurethane also emits toxic fumes if burned. Specific agents in polyurethane produce greenhouse gases like carbon dioxide.

Polyurethane definitely causes a negative impact on the environment.

Polylactic acid (PLA) is a plastic substitute made from fermented plant starch (usually corn). It is biodegradable and can be referred to as a ‘thermoplastic’. This means that PLA can liquify instead of burning, so it can return to its original state without much damage. This would mean easier recycling!

These bio-based polymers are a step forward into sustainable fashion. This can only be achieved by further research into the chemical makeup of more plants and crops that have less impact on the environment. This research is still continuing to produce more sustainable and eco friendly fashion alternatives to help develop the sustainable fashion industry even further. Next time you go shopping why don’t you have a look at whether your favorite stores source sustainable materials?

By Angelina Kim

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https://compareethics.com/ sustainable-fashion-101/ https://www.sustainyourstyle.org/en/ sustainableleather#:~:text=Leather%20will%20ne ver%20be%20an,need%20additional %20land%20and%20resources. https://www.tortoiseandladygrey.com/ 2016/05/02/environmental-impactsleather-fashion/ #:~:text=Around%2080%25%20of%20 leather%20worldwide,harm%20to%20i ndustrial%20tannery%20workers.&text =It%20is%20true%20that%20making, will%20not%20go%20to%20waste https://www.watsonwolfe.com/ 2018/09/22/what-is-vegan-leather/ https://www.ananas-anam.com/aboutus/ https://www.hunker.com/13414626/ the-disadvantages-of-polyurethane https://olivercompanylondon.com/ pages/applehttps://www.creativemechanisms.com/ blog/learn-about-polylactic-acid-plaprototypes

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Should we be Reconsidering our Lockdown Athleisure wear?

As we have faced lockdown after lockdown, going for months at a time without having to get dressed up to go anywhere or see anyone, it is safe to say that many of us have turned to more comfortable clothing, especially when having to face hours of online school and work. Athleisure and loungewear sets have finally become the fashion norm as people have continually been prioritising comfort to help get them through the day. As lockdown has given a lot of people more time on their hands, there has also been a huge increase in working out whether that be running, hopping on your peloton, or doing an at home cardio session - and as a result of all of these factors we are all spending a lot more time in Lycra.

To put it simply, leggings are the new black. And surely this is no cause for concern, if anything an increase in exercise is a good thing, right? But it seems that 34

there are actually several environmental consequences that come from both purchasing and using activewear.

The majority of activewear is made from synthetic materials, such as polyester, spandex/Lycra and nylon, which are all man-made, plastic based materials, and it is understandable as to why - no one wants to get to the end of a particularly energetic workout only to find that their clothes are drenched in sweat, and so manufacturers came up with a solution that would allow people to get a sweat on whilst also staying (relatively) dry.

Sweat wicking, breathable material has been without a doubt one of the most valuable inventions for both professional athletes and amateurs, but unfortunately it comes at a cost (and not just the ridiculously high prices of shops like lululemon and Sweaty Betty).

Whilst everyone is aware of the issue that ‘large’ plastic, products such as bottles and plastic bags, is causing, as well as the focus that has been on microbeads, which are the bright, colourful beads used in toothpastes and exfoliants under the names of polyethylene and polypropylene, so much so that they have now been banned in many countries, there has not been that much awareness surrounding microfibres.

Microfibres are tiny pieces of plastic which measure at about 100 times finer than a strand of human hair and they are found in all plastic fabrics,

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such as the ones used to make our activewear. When these clothes are washed, the microfibres get pulled out of the fabric and because they are so incredibly tiny, they are released into the water and eventually make their way into rivers, lakes and oceans.

Microfibres are usually not visible to the human eye and so they have often been overlooked as a problem, because, as the saying goes: out of sight, out of mind.

However, they are potentially even more damaging due to the fact that they can’t be seen - perhaps they aren’t as offensive to the eye as the floating plastic island in the Pacific Ocean, but at least those don’t end up in the food chain. As they are so small, microfibres are even being ingested by creatures such as plankton and worms which are right at the very start of the food chain, and from there they are passed on to fish, and scientists are increasingly finding samples of plastic in fish that humans are eating. Last year samples of plastic were even found in the placenta of a pregnant woman, showing that even unborn babies are being affected by this enormous problem.

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One of the most significant issues with microfibres is that once these plastics are out in the environment it is impossible for them to be discarded safely, as it is not only ‘new’ plastics that release these microfibres, but also recycled plastics. One potential solution is to install filters that are small enough to catch the microfibres so that they can be disposed of in landfills, which will reduce the amount in the ocean and subsequently in our food chain. But an arguably more urgent and sustainable solution is for companies to stop using fabrics made with microfibres all together, in favour of natural materials that will have a significantly smaller impact on the environment. However, that is easier said than done, especially in the case of activewear as manufacturers can’t just switch to cotton as it doesn’t have the same sweat proof effect that is so necessary.

Nevertheless, many sustainable brands have been exploring options that can be used to make their clothing more sustainable, both in terms of the fabrics themselves and the environmental impact of actually making the products. At this point in time, the majority of brands trying to reduce their environmental impact are recycling plastic - either in the form of single use plastic waste, like Adidas, or recycling polyester and nylon, like Tala - which, although not a perfect solution, does help to stop new plastics being created which at least reduces the total amount of plastic in the system. However, there are some brands which have gone even further

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and have created activewear out of natural materials. One example is the brand Pangaia, which uses both recycled cotton, cashmere and wool, as well as materials such as leather made from grapes and fabric from seaweed fibres. Another brand, Maikoda, uses bamboo and soy, along with organic cotton and lyocell (a synthetic fibre made from wood pulp) to make their athleisure apparel. This shows that brands are moving forward and evolving to help combat the increasingly urgent environmental problems that our world is facing.

Whilst a lot of these more environmentally friendly, sustainable brands can be rather expensive, many people will be happy spending significant chunks of money on name brand activewear, so why not take that money and put it towards a product that is equally as comfortable and durable, but infinitely better for the environment.

By Ella McKean References and further reading: https://lsponline.ca/2019/01/08/whatare-the-types-of-material-used-tomake-sportswear/ https://www.vogue.co.uk/article/whymicrofibres-are-the-new-microbeads https://www.wired.co.uk/article/ microbeads-international-bandamage-marine-life-plastic https://www.sciencedirect.com/topics/ chemistry/microfiber 36

https://forloveofwater.org/ microplastics-invading-the-food-chain/ https://www.theguardian.com/ environment/2020/dec/22/ microplastics-revealed-in-placentasunborn-babies https://www.stylist.co.uk/fashion/ ethical-activewear-uk-womenswimwear-gym-clothes-yoga-ecoenvironmentally-friendly-sustainablegreen/226744 https://thepangaia.com/pages/impactinnovative-materials https://mygreencloset.com/ecoexercise-brands/ https://schimiggy.com/lululemonfabric-guide-cheatsheet/

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The Future of Nanotechnology Nanotechnology is the manipulation of materials on an atomic or molecular scale and can involve the usage of nanoparticles, which are microscopic particles with at least one dimension less than 100 nanometers. Examples of prevalent nanomaterials include carbon based nanoparticles such as the buckminsterfullerene, graphene sheets and nanotubes, liposomes and metal based nanoparticles such as silver or gold. Nanotechnology, despite not being used yet on a larger scale, has huge potential implications in fields such as drug delivery, improving air quality and increasing the energy efficiency of products.

Much of the research going into nanotechnology is focused on drug delivery systems whose efficacy is thereby drastically improved by modification or usage of nanoparticles.

These tiny particles have the capacity to mitigate huge problems such as targeting cancer cells with excellent precision, permitted by their extremely high surface area to volume ratio compared to the same mass of 37

material in a larger form. This allows drug delivery to have reduced toxicity, improved efficacy and enhanced distribution. Nanoparticle drug delivery systems, on account of their minute size, can easily penetrate across barriers in small capillaries into single cells, for example the blood brain barrier, which allows the specific drug to accumulate at the targeted locations in the body more successfully.

Therefore this reduces the toxicity of the therapeutic agent as well as decreasing the drugs side effects and increasing treatment efficacy. The impact of the drugs side effects are reduced by nanoparticles not releasing the medicine till they reach the target cell or tissue, which prevents the drugs from damaging healthy tissues around the tumour, which are the cause of side effects. Furthermore, the therapeutic agents can be packed into nanoparticles that are unidentifiable by the human immune system essentially giving them “stealth mode” properties which allow antiviral drugs to target for example, human immunodeficiency virus (HIV) infected cells.

For example, cancer chemotherapy cytostatic drugs damage both malignant and normal cells alike.

However nano drug delivery, such as nanoshells coated with gold, selectively target malignant breast cancer cells only. This is done by combining infrared optical activity with properties of gold colloid, which allows the particle, of size smaller than 75 nanometers in diameter, to absorb and scatter the incidence of light.

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Antibodies to breast cancer can be directly attached to gold nanoshells, which strongly absorbs infrared light in contrast to normal tissue which is transparent to it. The nanoshellantibody complex binds strongly to cancerous cells only where an infrared laser will then heat up the nanoshells thereby destroying the cancer cells.

Nanotechnology is also being used to treat and improve the quality of air and water through separation and filtration, bioremediation and disinfection. This is vital as only 30% of all water on Earth is not trapped in ice or glaciers and only 0.08% of this is clean water, hence providing adequate safe and clean water is often a challenge.

Remediation is the process to remove, minimise or neutralise the water contaminants that damage human health or ecosystems. Traditional methods of remediation such as extraction and oxidation are less effective, expensive and timeconsuming. In contrast, an advanced method that can be used is nanomaterials which have enhanced affinity, capacity and selectivity for heavy metals and other contaminants in water. Using nanomaterials has wide ranging advantages including their higher reactivity, larger surface 38

contact and better disposal capabilities.

An example of this would be remediation using nanosized semiconductor photocatalysts. This is achieved through using materials such as titanium dioxide (TiO2), iron (III) oxide (Fe2O3) and zinc oxide (ZnO) which can serve as photocatalysts. In relation to air and water remediation, these photocatalysts are able to oxidise organic pollutant molecules into non toxic materials by light. At a sufficient level of light, the charge will be transferred from the valence band to the conduction band causing the surrounding substance to be oxidised.

Nanotechnology has allowed semiconductor photocatalysts, such as those described above, to be modified in terms of reactivity and selectivity.

Titanium dioxide is often used for remediation due to its low levels of toxicity, high photoconductivity and photostability as well as it’s easy availability and inexpensive nature. It has been trialed to remove contaminators from groundwater such as 1,1-dicholorethane, cis-1,1dischloroethane and toulene (methylbenzene). The surface of the TiO2 catalyst, which is developed using nanotubes, is proven to be more effective at eliminating organic materials in relation to the usual structure of TiO2. In effect, nanotechnology has an abundance of uses and provides more sophisticated and targeted solutions which are vital to mitigating prevalent environmental and health issues.

By Clara Gilardi

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References and Further reading: Yunus, Ian Sofian, et al.

“Nanotechnologies in Water and Air Pollution Treatment.” Environmental Technology Reviews, vol. 1, no. 1, Nov. 2012, pp. 136–148, 10.1080/21622515.2012.733966.

ALMEIDA, A, and E SOUTO. “Solid Lipid Nanoparticles as a Drug Delivery System for Peptides and Proteins .”

Advanced Drug Delivery Reviews, vol.

59, no. 6, 10 July 2007, pp. 478–490, 10.1016/j.addr.2007.04.007.

“Types and Preparation of Nanomaterials.” AZoNano.com, 17 Nov. 2015, www.azonano.com/ article.aspx?ArticleID=4147.

“Nanotechnology in the Chemical Industry.” Nano Magazine - Latest Nanotechnology News, nanomagazine.com/news/2018/6/27/ nanotechnology-in-the-chemicalindustry.

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Just as bronze, iron, and steel have driven new technological advances over the course of history, shaping societal developments and ultimately determining geopolitical superpowers we recognise today, a new materialgraphene- has the potential to alter our future today. Considered a ‘wonder material’ by scientists currently grappling over how to better understand it, graphene’s seemingly infinite list of remarkable characteristics could have drastic implications for the future of engineering and technology.

thin it is, but graphene is also flexible, transparent, highly conductive, and impermeable to most gases and liquids. Despite graphite being used since the Neolithic era, until recently graphene was a myth since scientists doubted if we would ever be able to isolate graphite down to a single, atom-thin sheet. Funnily enough the tool ultimately changing the world in this case was merely sellotape. By peeling layer after layer of graphite from a large block, scientists Andre Geim and Konstantin Novoselov were eventually able to generate the thinnest possible sample: graphene.

Since then, the list of potential uses has grown exponentially year after year.

Graphene is a single, thin layer of graphite, which is an allotrope of carbon. The carbon atoms in graphene are structured in a hexagonal arrangement resembling a honeycomb. Being one atom thick, graphene has already made history in being the first two-dimensional material ever discovered. Moreover, with a tensile strength of 130 gigapascals, it is over 100 times stronger than steel and one of the strongest materials known thus far.

Not only does graphene have an unbelievable strength considering how

Currently, our phones, laptops and other electronic devices rely on silicon as a key component. However, silicon transistors will soon be reaching the limit at which they can be effective, ultimately rendering these technologies slower and counterproductive. With graphene as their conductive element, it may be possible to manufacture ultra-thin and flexible touch screens that would be essentially unshatterable due to graphene’s strength. Smartphones would be as thin as a piece of paper, flexible, and light since touch screens can be printed on thin plastic rather than glass. Furthermore, graphene can be tuned to behave as both an insulator and a superconductor. This allows for both the investigation of unconventional superconductivity in science as well as opening many possibilities for new quantum devices.

Atom thick graphene: the new super material

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For example, graphene can be utilised for improving current protonconducting membranes, which are essential segments of fuel-cell technology. This combined with the fact that graphene’s impermeability to even the smallest of atoms still allows it to be used to sieve hydrogen atoms stripped of their electrons, indicates graphene could be used to construct mobile electric generators powered by hydrogen extracted from the air. In the future, vehicles and electronics could be fueled by small amounts of hydrogen in the air around us.

most pressing environmental concern, maintaining clean water supplies will become ever-increasingly crucial.

Over a billion people suffer from water scarcity, a figure that is constantly rising, and graphene filters could hold the billion dollar answer for improving water purification, and increasing the amount of safe freshwater available.

Moreover, engineers have recently developed a graphene filter called ‘Perforene’, which could reduce the amount of energy required for reverse osmosis in desalination plants to filter out salt of seawater.

From a less engineering-related standpoint, graphene could be invaluable for alleviating water shortages worldwide. Another exception to graphene’s impermeability is water as it can evaporate through graphene. This renders graphene an excellent tool for filtration and it could be incredibly helpful in purifying water of toxins.

Some of the most notorious environmental hazards, including nuclear waste and chemical runoff, could be cleansed from water thanks to graphene. Indeed, a study at the Royal Society of Chemistry proved oxidized graphene could even filter out radioactive materials such as uranium and plutonium present in water, leaving the liquid free of contaminants.

After nuclear incidents, like that of Chernobyl, which polluted food and water supplies all over Europe, a discovery like this can alleviate the growing global strain due to a dwindling freshwater supply. As overpopulation continues to be the

The potential uses of graphene are infinite. From hair dye to bulletproof vests and rust prevention measures.

One interesting potential use of graphene, however, is for mosquito defense. Although this is surprising, researchers at Brown University have devised a logical explanation: a graphene film on the skin physically blocks mosquitoes from biting, thanks to graphene’s impermeability, and also mitigates them from coming into contact with us in the first place. A possible explanation is that it prevents mosquitoes from being able to smell the prey, so perhaps there is some sort of chemical barrier within graphene.

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It is obvious by now that graphene has very many strengths and uses. Since its discovery 17 years ago, research has consistently identified new uses and ways to revolutionise not only science and engineering, but also society and health as a whole and we may be able to split other potentially

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semiconductor materials into atomthick layers. Although graphene is still extremely costly to produce in mass quantities, which consequently limits research possibilities, the future of graphene and its impact on humanity is bright. The existence of silicon was revealed almost a century before silicon semiconductors paved the way for computers. Only time will tell whether graphene will be the resource driving the next era of human history.

Just like the stone and bronze ages, we may even live in a graphene age one day.

By Tabitha Iliffe References and further reading: https://bits.blogs.nytimes.com/ 2012/10/12/graphene-could-usherflexible-ultra-slim-gadgets/?_r=0 https://www.treehugger.com/waysgraphene-could-change-theworld-4863867 https://www.explainthatstuff.com/ graphene.html https://www.theguardian.com/science/ 2013/nov/26/graphene-moleculepotential-wonder-material

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Marie Maynard Daly

NYU- essentially an academic award of distinction, awarded to very few students.

“Courage to be is the key to revelatory power of the feminist revolution.”- Dr Marie Maynard Daly

Of the most influential women in Chemistry, Marie Maynard Daly stands out significantly as being the first African American woman to obtain a PhD in the United States. She fought battles of both gender and racial bias whilst participating in crucial research involving the effects of biological molecules on the organisms. Not only is she an inspiration in the scientific field, she is also an inspiration to women and African Americans.

She was born on April 16, 1921, and raised in Queens, New York, in a modest household. Her father worked as a postman, after being forced to drop out of his degree in chemistry, at Cornell University, because he was unable to afford the tuition. Her mother had a passion for literature, which strongly influenced Marie as a child.

After graduating from her high school, Marie pursued her undergraduate degree at Queens College (also in New York) before moving onto her graduate degree, in chemistry, at New York University. She exceeded expectations at both schools, graduating ‘magna cum laude’ from 43

In 1943, Marie was admitted into the PhD program in chemistry at Columbia University, New York. This was a huge achievement for Marie, as a woman, and especially as a woman of colour.

As well as her immense hard work and diligence to earn this acceptance, she was also aided by the timing of her application. Due to many men leaving to fight in World War 2, there was a shortage of scientists working across the country. As a result, many schools were encouraging and admitting more women to enter the field and obtain PhDs. Led by the successful American chemist- Mary L Caldwell- Marie studied, in depth, the role of chemicals produced by the body in the process of digestion. After three years, she was awarded her doctoral degree in chemistry, officially securing her title as the first African American woman to receive a PhD in history.

Following her monumental achievement, Daly went on to be a professor of biochemistry at Columbia University. As well as this, she did a lot of research with other scientists on what heart attacks are caused by and, more importantly, the link between the fat cholesterol and how it blocks

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arteries (ultimately leading to heart attack.) Moreover, Daly was influential in developing multiple programmes to encourage minority students to enroll and attend science-related courses at universities across the country.

Eventually, she retired in 1986 and died in 2003 but her achievements as a scientist and woman of colour still remain an inspiration to young scientists all over the world.

By Aya Kodmani References and further reading: https://www.biography.com/scientist/ marie-m-daly https://www.sciencehistory.org/ historical-profile/marie-maynard-daly https:// blackhistory.news.columbia.edu/ people/marie-maynard-daly https://www.medicalnewstoday.com/ articles/dr-marie-maynard-daly-thefirst-black-woman-with-a-phd-inchemistry

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Editors’ Picks Our favourite books: Non-fiction The Poisoner’s Handbook - Deborah Blum The Disappearing Spoon - Sam Kean Herding Hemingway’s Cats - Kat Arney Why chemical reactions happen - James Keeler Mathemagics: How to look like a genius without really trying - Arthur T. Benjamin and Michael Shermer Fiction This Mortal Coil Series - Emily Suvada (seventeen-year-old Cat must use her gene-hacking skills to decode her late father’s message concealing a vaccine to a horrifying plague.)

Brave New World - Aldous Huxley (set in a futuristic World State, inhabited by genetically modified citizens and an intelligence-based social hierarchy.)

Do Androids Dream of Electric Sheep? - Philip K Dick (set in a post-apocalyptic San Francisco, where Earth's life has been greatly damaged by a nuclear global war, leaving most animal species endangered or extinct.)

Podcasts: Chemistry in its Element- a wonderful tour of the periodic table and the many chemical compounds found worldwide in a series of short episodes Stereo Chemistry- this is amazing for learning about chemistry’s frontiers and exciting research happening around us Chemistry in Everyday Life- explains chemical phenomena and how they manifest all around us

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Music:

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Teachers’ Picks Miss Mills- Antimony, Gold, and Jupiter’s Wolf: How the elements were named (By Peter Wothers)

Dr Hollis- Atkins’ Molecules (By Peter Atkins)

Miss McLaren- The Poisoner’s Handbook: Murder and the Birth of Forensic Medicine in Jazz Age New York (By Deborah Blum)

Mr Upton- Molecules of Murder (By John Emsley)

Ms Whitbyhttps://myheplus.com/subject/chemistry

Dr Harnett- “ChemistrySupport for sixth form studies” resources on the library website

Dr Badger- Chemistry: A Volatile History (BBC Four)

Miss Smarthttps://player.fm/podcasts/ Chemistry-Education (Collection of podcasts)

Miss Lloyd- Crash Course Chemistry on youtube

Ms Andrade- Why Chemical Reactions Happen (By James Keeler and Peter Wothers)

Mrs Swann- Shocking History of Phosphorus: A Biography of the Devil’s Element (By John Emsley)

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