SOUTHWEST RETORT
SEVENTY-FOURTH YEAR
March 2022
Published for the advancement of Chemists, Chemical Engineers and Chemistry in this area published by The Dallas-Fort Worth Section, with the cooperation of five other local sections of the American Chemical Society in the Southwest Region.
Vol. 74(7) March 2022 Editorial and Business Offices: Contact the Editor for subscription and advertisement information. Editor: Connie Hendrickson: retort@acsdfw.org Copy and Layout Editor: Lance Hughes: hugla64@gmail.com Business Manager: Martha Gilchrist: Martha.Gilchrist@tccd.edu The Southwest Retort is published monthly, September through May, by the Dallas-Ft. Worth Section of the American Chemical Society, Inc., for the ACS Sections of the Southwest Region.
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TABLE OF CONTENTS Fifty Years Ago………………………….......5 ARTICLES and COLUMNS Letter from the Editor…..…..……..............25 The Evolution of an Envirmental Scientist…..……………………………………….13 NEWS SHORTS A Potentially Longer-lasting Cholera Vaccine……….…………………………………..7 Increased Infectivity, Antibody Escape Drive SARS-CoV-2 Evolution, Studies Say...…….8 Broccoli and Kale Microgreens Pack a Nutritional Punch that Varies with Growing Conditions…………………......………..…..11 Colorfully Detecting Stressed-out Polymer Films, Gels before They Break (video)… .18
Tiny Probes could Sail to Outer Planets with the Help of Low-Power Lasers …………..19 ‘E-nose’ could Someday Diagnose Parkinson’s Disease by ‘Smelling’ skin..………...20 ANNOUNCMENTS
Contact the DFW Section General: info@acsdfw.org Education: ncw@acsdfw.org Elections: candidates@acsdfw.org Facebook: DFWACS Twitter: acsdfw
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INDEX OF ADVERTISERS Huffman Laboratories……………..…........3 TMJ Data Entry and Editing.………......…3 ANA-LAB…………………………...….…..4 Positions Available……………….....3, 7, 24
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Fifty Years Ago in the Southwest Retort DFW ACS Section initiates new local section award named after Wilfred T. Doherty. This award has been established to promote the advancement of chemistry and chemical engineering and to emphasize the role and contributions of these fields of science to modern society. This award publicly recognizes the contributions of scientists who have made meritorious advances in chemistry or chemical engineering in the area of the Dallas-Fort Worth Section. Accomplishments for the award must be significant, but they may arise in a plethora of areas. Possibilities are chemical research, teaching, ACS activities, establishment of a new chemical industry, solution of pollution problems, advances in curative or preventive chemotherapy, chemical physics, radiology, nuclear fission, biological engineering, geochemistry, plant chemistry, chemical genetics, or application of chemistry to health are some possible fields for consideration. Meritorious innovations in teaching chemistry or chemical engineering in high school, colleges, junior colleges, or universities will be considered also.
The person, persons, or groups to whom awards are given must be residents in the area assigned to the Dallas-Forth Section of the ACS. The work on which the award is based usually will have been done in this area. The award has been named for one of the four original trustees of the Robert A. Welch Foundation, whose deep interest in March 2022
science, particularly chemistry, has been a cohesive force in this area for many years. Wilfred Thomas (Doc) Doherty was one of those founding trustees and was President of the Robert A. Welch Foundation at the time of his death on Nov. 16, 1971. Doherty’s warmth, humanity, enthusiasm, vigor Compiled by E. Thomas and interest in chemistry contributed vastly to his imStrom portant role in leading chemical research in Texas from its slow beginnings to its present high status. Morton Mason wins initial ACS DFW Doherty Award. Dr. Morton Mason, Professor of Clinical Chemistry at UTSouthwestern Medical School and Director of the Dallas-City County Criminal Investigation Laboratory is the first winner of the section’s Doherty Award. Dr. Mason has been on the faculty of the medical school since 1944, the year after the school was founded. A recognized research authority, he is the author of 65 publications dealing with kidney and liver physiology, hypertension, analytical toxicology and electrolyte distribution. A native of Pasadena, CA, Dr. Mason received his doctorate from Duke in 1934. He served on the faculties of Duke and Vanderbilt’s departments of medicine before coming to Dallas. The ACS tour speakers for March are Dr. Martin S. Frant from Orion Research
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Fifty Years Ago
2021 DFW Section Officers
continued from page 5
Chair: Trey Putnam speaking on “Recent Industrial Applications of Ion Electrodes,” Dr. Howard V. Malmstadt of the University of Illinois discussing “Digital and Analog Instrumentation for Scientists,” and Dr. Robert L. Burwell, Jr. of Northwestern talking on “Hydrogenations and Related Reactions on Metallic Catalysts.” The DFW ACS Section’s Meeting-inMiniature will be held on Friday, April 28, at Texas Woman’s University. TWU faculty member L. C. Sams attended the first winter fluorine conference held in St. Petersburg, FL Jan. 23-29. Faculty member Lyman Caswell and student Daisy Lee gave a presentation at the San Antonio ACS SW Regional Meeting. Dr. Peggy Dunlap of Mobil’s Dallas Field Research Laboratory was appointed to the ACS Women Chemists Committee. At UTDallas Dr. Harold Werbin presented a paper at the 16th annual Biophysical Society meeting held Feb. 24-27 in Toronto. At East Texas State University Drs. L. Bone and D. Quane received two year Welch Foundation grants for $24,000. At Texas Tech Prof. William Herndon will present seminars on his theoretical organic research at Utah, Colorado, and Utah State universities. Dr. Edward Janzen of the University of Georgia gave a seminar here.
Chair-elect: Mihaela C. Stefan Past Chair: Mihaela C. Stefan
Treasurer: Martha Gilchrist Secretary: Heidi Conrad Councilors: Mary Anderson, Linda Schultz, E. Thomas Strom, and Jason McAfee Alternate Councilors: Michael Bigwood, John McIlroy, Daniela Hutanu, and Danny Tran
POSITIONS AVAILABLE Texas Christian University (Fort Worth, TX) is looking to hire several adjuncts to supervise General Chemistry Labs in Spring 2022. Ph.D. preferred, M.S. or Ph.D. in progress will be considered. Post-docs looking for teaching experience or retired teachers are encouraged to apply.
Send your resume to kayla.green@tcu.edu
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From the ACS Press Room
A Potentially Longer-lasting Cholera Vaccine “Virus-like Particle Display of Vibrio cholerae O-specific Polysaccharide as a Potential Vaccine against Cholera” ACS Infectious Diseases Cholera, a diarrheal disease caused by the highly transmissible bacteria Vibrio cholerae, kills tens of thousands of people each year worldwide. Current vaccines last only 2 –5 years, and they don’t work very well in young children. Now, researchers reporting in ACS Infectious Diseases have developed a new type of cholera vaccine consisting of polysaccharides displayed on virus-like par-
endemic countries. The immune system produces antibodies against the O-specific polysaccharide (OSP) on the surface of V. cholerae, but this polysaccharide in isolation does not generate a strong, long-lasting immune response. Peng Xu, Edward Ryan, Xuefei Huang and colleagues wondered if attaching OSP to virus-like particles could induce stronger, longer-lasting immunity.
So the researchers developed a method to efficiently link multiple copies of OSP to Qβ, a virus-like particle that infects bacteria. The modified virus-like particles were recognized by antibodies in blood taken from recovering cholera patients, but not from patients with typhoid, another bacterial disease. Next, the team immunized mice with Qβ-OSP, observing that three doses caused a strong antibody response that persisted at least 265 days after the first dose. The immunized mice had antibodies that recognized the OSP from the natural lipopolysaccharide of V. cholerae. When the researchers mixed serum antibodies from A virus-like particle (Qβ-OSP conjugate) disthe mice with other immune system proteins playing a polysaccharide from Vibrio cholerae that kill bacteria and with live V. cholerae, anbacteria generates a strong, long-lasting imtibodies from two of the five mice triggered mune response in mice. more bacterial death than those from mice imticles. The vaccine generated long-lasting munized with Qβ alone. The virus-like partiantibody responses against V. cholerae in cle could mimic natural bacteria by presenting multiple copies of OSP on its surface, the remice. searchers say, and it warrants further evaluaCurrent cholera vaccines contain killed or tion as a next-generation cholera vaccine. weakened V. cholerae bacteria and are administered orally. They offer the lowest level The authors acknowledge funding from the NIH, the Fogarty International Center and and duration of protection in young children, Michigan State University. Xuefei Huang is who are commonly affected by cholera in the founder of Iaso Therapeutics Inc. March 2022
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From the ACS Press Room
Increased Infectivity, Antibody Escape Drive SARS-CoV2 Evolution, Studies Say “Emerging Vaccine-Breakthrough SARSCoV-2 Variants” ACS Infectious Diseases “Omicron Variant (B.1.1.529): Infectivity, Vaccine Breakthrough, and Antibody Resistance” Journal of Chemical Information and Modeling First announced by the World Health Organization on Nov. 26, 2021, the SARS-CoV-2 omicron variant spread rapidly around the world, becoming the dominant variant in the U.S. and elsewhere. Now, researchers report in ACS Infectious Diseases and the Journal of Chemical Information and Modeling that omicron and other variants are evolving increased infectivity and antibody escape, according to an artificial intelligence (AI) model. Therefore, new vaccines and antibody therapies are desperately needed, the researchers say.
Then, they used an AI model to predict how these mutations affect binding strength of the RBD to ACE2 and to 130 antibody structures, including several monoclonal antibodies used as therapies. The team found that mutations to strengthen infectivity are the driving force for viral evolution, whereas in highly vaccinated populations, mutations that allow the virus to escape vaccines become dominant. The researchers also predicted that certain combinations of mutations have a high likelihood of massive spread.
In another study in the Journal of Chemical Information and Modeling, Wei and colleagues took a deep Understanding how SARS-CoV-2 evolves is dive into essential to predicting vaccine breakthrough the omicron and designing mutation-proof vaccines and variant’s infectivity, vaccine breakthrough monoclonal antibody treatments. In a recent and antibody resistance. They used their AI study in ACS Infectious Diseases, Guo-Wei model to analyze how the variant’s unusually Wei and colleagues analyzed almost 1.5 mil- high number of mutations on the spike prolion SARS-CoV-2 genome sequences taken tein affect RBD binding to ACE2 and antifrom people with COVID-19. They identified bodies. Their results indicated that omicron is 683 unique mutations in the receptor binding over 10 times more infectious than the origidomain (RBD), the region of the SARS-CoV nal coronavirus and 2.8 times more infectious -2 spike protein that attaches to the human continued on page 21 ACE2 receptor on the surface of human cells.
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The Doherty Award is given for excellence in chemical research or chemistry teaching, meritorious service to ACS, new chemical methodology (for the industry), solution of pollution problems, and advances in curative or preventive chemotherapy. Nominees may come from industry, academia, government, or small business. The nominee should be a resident member in the area served by the ACS DFW Local Section, and the work should have been performed here. The award is $1500 and an engraved plaque.
The Schulz Award is given to high school chemistry teachers, who, like the late Dr. Werner Schulz, bring that something extra to the teaching of chemistry. The nominee and/or nominator need not be ACS members. Nominees should show excellence in chemistry teaching, as demonstrated by testimonials from students and fellow teachers, results in student competitions, and diligence in updating and expanding scientific/teaching credentials. The award is $1500 and an engraved plaque. The DFW Section instituted the Chemistry Ambassador Award to recognize an outstanding Section member who has made a significant impact by promoting chemistry to the community. The 2022 Chemistry Ambassador of the Year award is based on peer or selfnominations to the selection committee. Submissions should be one page in length and address the community outreach activities either through teaching, service, or working with legislators to affect public policy. Submissions will be evaluated on the impact made, which may include but not limited to how many people were reached, impact on individual people in the community, and exemplary commitment to the promotion of chemistry in the community. The award is $1000. Each nomination should contain a completed nomination form, a cover letter highlighting the nominee’s accomplishments, and a copy of the CV. One or two additional letters may accompany nominations. The nomination package should be sent by email as a single pdf file Dr. Gabriele Meloni at gabriele.meloni@utdallas.edu. Nominations remain active for five years but should be updated annually. The deadline is May 01, 2022
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From the ACS Press Room Broccoli and Kale Microgreens Pack a Nutritional Punch that Varies with Growing Conditions “Profiling of Polyphenols and Glucosinolates in Kale and Broccoli Microgreens Grown under Chamber and Windowsill Conditions by Ultrahigh-Performance Liquid Chromatography High-Resolution Mass Spectrometry” ACS Food Science & Technology Although microgreens were initially gourmet ingredients for upscale restaurants, they’ve become popular among gardeners and home cooks. Despite their “superfood” label, the levels of healthful compounds, such as phytonutrients, in most varieties of microgreens are unknown. Researchers in ACS Food Science & Technology now report that kale and broccoli microgreens grown in either windowsills or under commercial growing conditions are rich in phytonutrients, though the levels of some compounds varied considerably between the two environments.
As indoor gardening has taken off in recent years, microgreens have added a pop of color to the windowsills of many homes. The most commonly planted varieties of these small seedlings are from the Brassica family, which includes broccoli, kale, cabbage and mustard. The mature, fully-grown versions of these vegetables are rich in vitamins, minerals and March 2022
phytochemicals, and environmental conditions can impact the plants’ nutritional contents. But not much is known about the levels of these compounds in young microgreens. In a previous study, Thomas Wang, Pei Chen and colleagues observed that red cabbage microgreens had higher amounts of phytonutrients that have been reported to have antioxidant and anticancer properties, including polyphenols and glucosinolates, than the fullgrown vegetables. However, similar assessments haven’t been done on other Brassica seedlings. So, the researchers wanted to measure the levels of polyphenols and glucosinolates in broccoli and kale microgreens, and then compare data from those grown on windowsills to those raised in commercial growth chambers. The researchers placed trays of newly planted broccoli and kale seeds either on a windowsill in natural sunlight or inside a temperature- and humidity-controlled refrigeratorlike growth chamber with artificial sunlight for 12 hours a day. Ten full days after seeding, the team harvested the plants and assessed the phytonutrient content with a liquid chromatography high-resolution mass spectrometry system. The broccoli and kale microgreens were rich in polyphenols and glucosinolates, no matter how they were grown. But there was considerable variability in the amounts of individual compounds when comparing the two growth environments. For continued on page 24
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Now accepting applications for fall 2022 Ph.D Program The Department of Chemistry and Biochemistry at the University of Texas at Dallas is now accepting applications for the fall 2022 Ph.D. program. We have 24 tenuretrack research active faculty, 8 professors of instruction, and 120 graduate students. The Ph.D. program focuses on innovation and problem-solving in interdisciplinary, cutting-edge research areas such as organic and inorganic materials, nanotechnology, biochemistry, and polymer chemistry, preparing graduates with the following skills: •
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The Evolution of an Environmental Scientist Part I “There are very few living organic peroxide chemists,” warned my first professor of organic chemistry when introducing that relatively brief topic at the end of our second semester. I instantly recalled this precaution some years later when I accidentally dropped a several-pound container of benzoyl peroxide and caught it before it could hit the floor and detonate. This early alert about this acute, if personal environmental insult, thus made a valuable impression on me. However, this was not my only introduction to environmental exposure back in the 20th Century! Hopefully, I am one of the few who has lost a chemist colleague to a chemical hazard, in this case to carbon monoxide.
Dr. Robert “Bob” Landolt
Other chemists may have similar experiences, but other factors subsequently stimulated my personal concern for environmental impacts. In grad school, I was a shocked at the very bitter comment about Rachel Carson’s Silent Spring from a respected faculty member who stated, “that woman is going to ruin everything.” This 1960s attitude resulted from publicity that chemicals constituted unanticipated hazards to birds and the food chains generally. Lesson learned? There are risks to ubiquitous introduction of money-making products into the environment! As a 1960s post-doc, two other experiences impressed to me the need for safety considerations upon exposure to chemicals. The first occurred during two years of very careful work using sodium cyanide as a reagent: “Keep that damn stuff in the hood!” Even novices knew of its danger, due in part Nazi practices in WW II. The second was slow recognition of chronic consequences in our lab when a colleague conducted column chromatography on an open bench. The problem arose when he practiced eluting with chlorinated solvents as well as benzene. At the same time, the general public was at risk when living close to industrial facilities known to belch these things routinely! A health problem may even arise when a common substance, expected safe, is used. Our family experienced this after our three children, upon recovery from chicken pox, developed life threatening cases of Reye’s Syndrome , which widely impacted children in the Midwest in the late 1970s. Our kids recovered with excellent medical care, but I was stimulated to help determine causative agents experienced in common by Reye’s patients. I claim no distinctive contribution to this effort, but ultimately it was discovered that aspirin was the culprit. Read the label on your aspirin bottle! Moreover, the environment has been ‘insulted,’ even from more ubiquitous/routine use of something as common as drinking water, as it became obvious to me upon conducting reMarch 2022
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search about exposing coal to hypochlorite. What’s coal got to do with drinking water? At the same time in the mid 1970s that I explored using bleach to useful products from coal, others discovered the unexpected presence of chloroform and some of its cousins in drinking water. Chlorine was found not only to kill bacteria but also to cause certain organic compound generation in raw water during widely-used disinfection practices, including for swimming pools! My most direct early involvement with a notable environmental problem occurred in 1980 on projects to understand how best to clean up ‘priority pollutant sites’ identified in the 70s. Subsequent research focusing on how pH influences such results led me to coauthor a series of publications with my students. We showed how the chlorinated compounds and unexpected pH changes resulted during hypochlorite reactions similar to those going on when folks sanitize clothes in washing machines! At the Radian corporation in 1980 I joined efforts to mitigate public exposure to hazardous stuff. This required extensive use of online resources, to see how our work dovetailed with that of scientists generally. Online access was equally important a short time later when I was invited work an environmentally focused project at the Naval Research Lab, to understand the best way to combat chemical warfare agents with hypchlorite. One does not have to go to scientific literature to know why this was a concern for the Navy, due to Cold War interest by the Russians in nerve agents. Significantly, bleach was a recognized way to counteract chemical warfare agents, but factors governing its reactivity required further study. From studies at Texas Wesleyan, we had learned that chloroform was a reaction product from citric acid, with reactivity dependent on pH. The Navy had found that the buffering agent, citric acid/citrate, decomposed hypochlorite at the pH of seawater. This led to research for the Navy Lab, farmed out to us at Wesleyan, that demonstrated bleach stability in sea water. Environmental hazards with acute impacts tend to get quick attention, but the story is far more complicated when the threat is chronic. Not only do chronic threats require more than raising public consciousness, but also managing remedial efforts requires much more than scientific input, especially when military, government or private business is involved. Case in point: ‘priority pollutant’ (and associated ‘Superfund” sites) management. A comparable challenge was learning to deal with Climate Change. PART 2 “What we need is one-handed scientists,” said the Committee Chair, frustrated by ‘expert’ panelist’s reluctance to be pinned down regarding causes for the Ozone Hole. The occasion was a Congressional Hearing on potential remedies for the recently discovered Hole discovered at antarctica. As an ACS Congressional Assistant Fellow with Jim Wright in the mid 1980s I attended this and other hearings. This occasion focused not only on this threat, but also raised alarm that a concerted, multi-nation effort would be required. Fortunately, March 2022
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there’s evidence of Ozone Hole remediation through halocarbon regulation, but it’s taken some time! Beside war, famine, and attendant problems of global proportion, the world began to recognize shortfalls of energy supplies during the “energy crisis” in 1973. It became increasingly obvious that sustainable energy sources were going to become important, especially when nuclear power lost its attractiveness due to Chernobyl and Three Mile Island accidents. Making fossil fuels more available through fracking etc., has drawn attention to a host of environmental problems from ‘greenhouse gases’ including carbon dioxide emissions from combusting coal, oil, and natural gas. When highly profitable businesses are impacted, economic as well as environmental factors come into play. Conservation routinely is practiced as a last resort. Some time ago when home builders were told that alternatives, including electric heating would be required, their reported response was, “Now we’ll have to insulate!” It's not an overstatement that, "The best way to learn something is to teach it" Providentially for me, teaching environmental courses for non-science majors at Texas Wesleyan included conveying the challenges of climate change. Further, in the 21 st Century, the American Chemical Society (ACS) authorized development of its Climate Science Toolkit. An associated planning grant has enabled DFW ACS Section to sponsor programing, which for years served North Texas Community College Faculty as well as church and civic organizations. Our activities were recognized by an ACS ChemLuminary Award in 2017!
Being human brings us all to hold beliefs in high regard, but when it comes to Climate Change issues, please consider Bernard Baruch’s admonition, “Every man has a right to his opinion, but no man has a right to be wrong in his facts.” It’s been useful to interact with diverse audiences using insights drawn from “This Spaceship Earth,” cartoons, and communication with the public.
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Understanding the past may be easier that predicting the future, but the latter is important for decision making. Significantly, scenarios may be generated using computer technology, allowing users to show the predictable impacts of decision making. Like the weather, time will tell the utility of such predictions. Cole, Voyage of Life Paintings: video at https://www.youtube.com/watch? v=e0tKdL0QcgQ&t=27s https://www.ccohs.ca/oshanswers/chemicals/organic/organic_peroxide.html https://pubmed.ncbi.nlm.nih.gov/33657411/#:~:text=Environmental%20insults% 20impair%20human%20health,of%20chemicals%20and%20environmental% 20stressors. https://www.acs.org/content/acs/en/education/whatischemistry/landmarks/rachelcarson-silent-spring.html https://encyclopedia.ushmm.org/content/en/article/at-the-killing-centers
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https://www.epa.gov/toxics-release-inventory-tri-program; earlier, https:// www.sciencedirect.com/science/article/abs/pii/S0095069696909559
https://www.uspharmacist.com/article/reyes-syndrome-a-rare-but-serious-pediatriccondition https://www.osti.gov/biblio/7308254-chemicals-derived-from-coal-battellehydrothermal-coal-process https://www.cdc.gov/healthywater/global/household-water-treatment/chlorinationbyproducts.html?CDC_AA_refVal=https%3A%2F%2Fwww.cdc.gov% 2Fsafewater%2Fchlorination-byproducts.html
“Hypochlorite-Induced Ipso-Substitution Reactions of Aromatic Alcohols and Related Compounds,” Synlett, 2011(14): 2069-2071 and references cited therein. https://chemm.hhs.gov/countermeasure_sodium-hypochlorite.htm https://pubs.acs.org/doi/pdf/10.1021/jo00366a040
https://www.epa.gov/superfund/what-superfund https://www.unep.org/ozonaction/who-we-are/about-montreal-protocol https://www.theweathernetwork.com/en/news/climate/solutions/ozone-layer-hole-that -was-once-larger-tan-antarctica-has-finally-closed. “Ohio Energy Seminar,” Columbus, 1973. https://www.quora.com/The-best-way-to-learn-something-is-to-teach-it-How-much-is -this-true-for-you-Can-you-deepen-the-concept
https://www.acs.org/content/acs/en/climatescience.html “Climate Science Is the Answer, But What are the Questions?” https://www.acs.org/ content/dam/acsorg/climatescience/challenge-grant-recepients.pdf
https://thisspaceshipearth.org/ https://climatecommunication.org/wp-content/uploads/2011/10/Somerville-HassolPhysics-Today-2011.pdf
https://en-roads.climateinteractive.org/scenario.html?v=22.1.1
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From the ACS Press Room
Colorfully Detecting Stressed-out Polymer Films, Gels before They Break (video) “Ratiometric Flapping Force Probe That Works in Polymer Gels” Journal of the American Chemical Society Stretchy films and squishy gels help make wearable electronics, soft robotics and biocompatible tissues a reality. But too much force can cause these polymers to break apart without warning. To detect stress before it’s too late, researchers reporting in the Journal of the American Chemical Society show they have designed a compound with “wings” that makes these materials change color when they are stretched or crushed. Watch a video of the materials here. Youtube ID: Lu4j3Qn8m0U
Plasticky films and polymer gels — soft 3D networks filled with liquids — can be bendable, stretchable or compressible. And while most polymer films only snap apart when pulled too far, many gels aren’t very strong, cracking under relatively small amounts of pressure. Yet there isn’t a way to predict how tough the spongy material will be. In previous research, Shohei Saito and colleagues developed V-shaped molecules, known as flapping molecular (FLAP) force probes. FLAPs have two side structures resembling wings that flatten under pressure, causing a color change from blue to green fluorescence. This probe worked as expected when incorporated into a polyurethane film, but when added to a liquid-soaked polymer gel, the compound spontaneously turned fluorescent green without any external force.
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So, Saito and Takuya Yamakado set out to improve the FLAP molecule so that it would accurately detect mechanical stresses in both a polymer gel and a film. The researchers modified their earlier version by replacing the two anthraceneimide wings with pyreneimide ones, attaching them to opposite sides of the same flexible central cyclooctatetraene joint. When they added the probe into a polymer film and stretched the material, its fluorescence shifted strongly from blue to green. It also produced a color change that was visible to the naked eye. Next, the researchers incorporated the new FLAP probe into a polyureA FLAP probe with thane gel soaked in an “wings” makes polymer films and gels organic solvent, creating change color when they a yellow cylinder that are stretched or fluoresced blue, and crushed. then compressed the material. The cylinder’s fluorescence became measurably greener as more pressure was exerted. In their final test, the researchers placed metal letters F-L-A-P on a rectangular block of the gel. They used maps of the green to blue fluorescence ratio to calculate the pressure each letter placed on the gel below, which ranged from 0 to 1 MPa. The researchers say this study could help them develop tougher gel materials and nanoscale tension probes for cell membranes.
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From the ACS Press Room Tiny Probes could Sail to Outer Planets with the Help of Low-Power Lasers “Low-Power Laser Sailing for Fast-Transit Space Flight” Nano Letters Space travel can be agonizingly slow: For example, the New Horizons probe took almost 10 years to reach Pluto. Traveling to Proxima Centauri b, the closest habitable planet to Earth, would require thousands of years with even the biggest rockets. Now, researchers calculate in ACS’ Nano Letters that lowpower lasers on Earth could launch and maneuver small probes equipped with silicon or boron nitride sails, propelling them to much faster speeds than rocket engines. Instead of catching wind, like the sails on boats, “laser sails” would catch laser beams and could, in principle, push spacecraft to nearly the speed of light. Scientists have been working on this concept for In this illustration, a lowa while. For exam- power laser (red cone) on ple, one privately Earth could be used to shift funded project the orbit (red lines) of a small probe (grey circle), or called the Break- propel it at rapid speeds to through Starshot Neptune and beyond. initiative aims to send a small, sailed probe weighing about a gram to Proxima Centauri b with a flight taking only 20 years. It would be propelled to 20% of light speed by a 100 GW, kilometersquare laser array. Ho-Ting Tung and Artur Davoyan wondered if much lower-power, March 2022
smaller laser arrays could find use in applications where conventional electric and chemical rockets are now used. The lasers might someday be able to adjust the orbit of satellites after launch or propel tiny sailed probes on interplanetary or interstellar missions, without requiring large amounts of fuel. The researchers performed calculations to show that even lasers with powers of about 100 kW and array sizes of about a meter could power a 1-gram probe at velocities far exceeding the current record, with only minutes to hours of laser illumination. According to their calculations, the lasers could maneuver small probes between different Earth orbits in only a day, which is not possible with current electrical and chemical rockets. The team determined that the best materials for the laser sails, which allowed high reflectivity and rapid cooling, were silicon nitride and boron nitride structured at the nanoscale. Finally, the researchers calculated that these tiny laser-propelled probes could travel fast enough to escape the solar system, reaching 5 times higher velocities than the New Horizons probe. These prototype sailed spacecraft, driven by low-power lasers, could pave the wave for fast space exploration and future interstellar flight, the researchers say.
The authors acknowledge funding from NASA, the Air Force Office of Scientific Research, UCLA and the Hellman Society of Fellows.
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From the ACS Press Room
‘E-nose’ could Someday Diagnose Parkinson’s Disease by ‘Smelling’ Skin (GC)-mass spectrometry to analyze odor compounds in the sebum of people with PD. But the instruments are bulky, slow and exACS Omega pensive. Jun Liu, Xing Chen and colleagues wanted to develop a fast, easy to use, portaA couple of years ago, a woman named Joy ble and inexpensive GC system to diagnose Milne made headlines when scientists discov- PD through smell, making it suitable for ered that she could “smell” Parkinson’s dispoint-of-care testing. ease (PD) on people with the neurodegenerative disorder. Since then, researchers have The researchers developed an e-nose, combeen trying to build devices that could diag- bining GC with a surface acoustic wave sennose PD through odor compounds on the sor — which measures gaseous compounds skin. Now, researchers reporting in ACS through their interaction with a sound wave Omega have developed a portable, artificially — and machine learning algorithms. The intelligent olfactory system, or “e-nose,” that team collected sebum samples from 31 PD could someday diagnose the disease in a doc- patients and 32 healthy controls by swabbing their upper backs with gauze. They analyzed tor’s office. volatile organic compounds emanating from PD causes motor symptoms, such as tremors, the gauze with the e-nose, finding three odor rigidity and trouble walking, as well as non- compounds (octanal, hexyl acetate and perilmotor symptoms, including depression and lic aldehyde) that were significantly different dementia. Although there’s no cure, early di- between the two groups, which they used to agnosis and treatment can improve one’s build a model for PD diagnosis. quality of life, relieve symptoms and prolong survival. However, the disease usually isn’t Next, the researchers analyzed sebum from identified until patients develop motor symp- an additional 12 PD patients and 12 healthy toms, and by that time, they’ve already expe- controls, finding that the model had an accurienced irreversible neuron loss. Recently, racy of 70.8% in predicting PD. The model scientists discovered that people with PD se- was 91.7% sensitive in identifying true PD crete increased sebum (an oily, waxy sub- patients, but its specificity was only 50%, instance produced by the skin’s sebaceous dicating a high rate of false positives. When glands), along with increased production of machine learning algorithms were used to anyeast, enzymes and hormones, which com- alyze the entire odor profile, the accuracy of bine to produce certain odors. Although hu- diagnosis improved to 79.2%. Before the eman “super smellers” like Milne are very ra- nose is ready for the clinic, the team needs to re, researchers have used gas chromatography test it on many more people to improve the “Artificial Intelligent Olfactory System for the Diagnosis of Parkinson’s Disease”
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From the ACS Press Room accuracy of the models, and they also need to consider factors such as race, the researchers say. The authors acknowledge funding from the National Natural Science Foundation of China, the National Key Research and Development Program of China, the Zhejiang Public Welfare Technology Application Research Project, the Key Research and Development Program of Shaanxi, the Major Scientific Project of Zhejiang Lab, the Zhejiang Provincial Natural Science Foundation of China, the China Postdoctoral Science Foundation and the Major Consulting Project of the Chinese Academy of Engineering.
“Detecting Stressed-out Polymer Films” Continued from page 18
The authors acknowledge funding from a Japan Science and Technology Agency PRESTO (FRONTIER) grant, a Japan Science and Technology Agency FOREST grant, a Japan Society for the Promotion of Science KAKENHI grant, a Japan Society for the Promotion of Science Fellowship, the Inoue Foundation for Science and the Toray Science Foundation.
“Increased Infectivity” Continued from page 8 than the delta variant. In addition, omicron is 14 times more likely than delta to escape current vaccines, and it is predicted to compromise the efficacy of several monoclonal antibody therapies. Many of these predictions have been verified by emerging experimental results, stressing the importance of developing a new generation of vaccines and monoclonal antibodies that won’t be easily affected by viral mutations, the researchers say. The authors acknowledge funding from the National Institutes of Health, the National Science Foundation, NASA, the Michigan Economic Development Corporation, the Michigan State University Foundation, Bristol-Myers Squibb and Pfizer.
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From the ACS Press Room
“Broccoli and Kale” Continued from page 11 instance, three flavanol compounds that contribute to the plant’s dark color and bitter taste were higher in windowsill-grown microgreens. However, chamber-grown plants had higher levels of two glucosinolates, which are antioxidant- and anticancerrelated compounds. Overall, the growth environment for kale and broccoli microgreens affects the abundance of individual phytonutrients, the researchers say, which could affect their flavor and potential health benefits. The authors acknowledge funding from U.S. appropriated funds to the U.S. Department of Agriculture, Fundamental Research Funds for the Central Universities of China and the State Scholarship Fund of China Scholarship Council.
Title: Lecturer of Chemistry Employer/Institution: University of North Texas Salary: Competitive salary & benefits Location: Denton, TX The Department of Chemistry at UNT invites applications for a full-time, non-tenure track faculty position at the rank of Lecturer or, to begin in August 2022. Applicants should have a Ph.D. in Chemistry or a related field and some teaching experience. Primary duties for the position will be in our high-enrollment General Chemistry and/ or Organic Chemistry courses, which serve as important gateway courses for students in STEM majors and have a major impact on students’ ability to attain their educational goals. The University of North Texas (UNT) is a Carnegie R1 research university and a federally designated Hispanic-Serving Institution and MinorityServing Institution, with a diverse population of over 40,000 students. The selected candidate will have opportunities to interact with many established programs on campus that focus on chemistry and science education, including the Teach North Texas (TNT) teacher training program and the Texas Academy of Mathematics & Science (a residential magnet high school for high achievers). For additional information and to apply for the position, visit our job application website at http:// jobs.untsystem.edu and search for Posting Number F735P (Lecturer). Applicants should submit a cover letter, curriculum vitae, statement of teaching philosophy, and a diversity statement. In addition, please supply names and contact information for three professional references, and arrange for three reference letters to be emailed to chemjobs@unt.edu with “Lecturer” in the email subject line. Evaluation of applications will begin on February 20, 2022 and will continue until the position has been filled.
UNT is an Affirmative Action/Equal Opportunity/ Veteran/ADA Employer. The UNT Chemistry Department is dedicated to creating a climate that values diversity, equity, and inclusion, and we welcome applications from people of color, women, and LGBTQ+ individuals.
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From the Editor
Registration for the Meeting-in-Miniature is still open, as well as registration of the Chemistry Olympiad qualifying exam.
Awareness of the COVID crisis and omicron variant is widespread (see page 8), but there are other endemic infections still afloat in some parts of the world. For example, chlolera, a diarrheal disease caused by Vibrio cholerae, kills many, many people each year worldwide. Cholera vaccines are available but last only 2–5 years; the available vaccines are not as effective in young children (who are especially susceptible). A new vaccine formed by attaching a polysaccharide to virus-like particles (Peng Xu, Edward Ryan, Xuefei Huang and colleagues) shows great promise in induction of stronger, longer-lasting immunity. Last, but by no means least, we have an article by Bob Landolt on the his journey to environmental consciousness and responsibility, something all of us have experienced.
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