Synthesis, characterization, and photothermal effect of CuS nanoparticles deposited over graphene nanosheets
Paris Semien Mentor: Gururaj Neelgund Department of Chemistry Introduction: The employment of near-infrared (NIR) radiations in photothermal therapy (PTT) to treat cancer is a current high-pitched interest aside from its classical applications such as telecommunication, sensing ablation, etc. [1]. The reason is that the NIR region (700-1100 nm) is an ideal clinical phototherapeutic window for PTT as attenuation of NIR radiations by skin, blood, and tissues is low, and it allows for the treatment of deep-seated tumors. [2]. The application of PTT in the treatment of tumors has been identified as a minimally invasive alternative to conventional hyperthermia treatment owing to its remote controllability, low systemic toxicity, and minor side effects [3]. While the implementation of PTT relies on the development of suitable photothermal coupling agents. On account of the importance of photothermal agents in PTT, herein, we designed the robust NIR active agent, GR-CuS, by deposition of CuS nanoparticles over graphene (G.R.) nanosheets. Materials and Methods: Preparation of GR-CuS: Graphene oxide (G.O.) needed to produce G.R. nanosheets was obtained by the Hummers and Offerman method with slight modifications [4,5]. Then G.O. (50 mg) was dispersed in EtOH (50 mL) by sonication for 5 mins, subjected to centrifugation, and EtOH was removed. Then G.O. was re-dispersed in ethylenediamine (EDA) to yield the yellow-brown suspension, which was subjected to refluxing for 1 hr at 80 °C. The resulting black suspension of G.R. nanosheets was then centrifuged, subsequently washed with EtOH and DI water, and dried under vacuum at 40 °C for five h. Subsequently, 100 mg G.R. nanosheets were dispersed in 50 mL DI water by sonication, and 20 mL aqueous solutions of CuCl2 (0.01 mol) and Na2S (0.01 mol) were added to it. The resulting mixture was allowed to stir for 4 hr at room temperature to yield GR-CuS. Results and Discussion: The prepared GR-CuS will be characterized using various instrumentation viz., IR, UV-vis-NIR, XRD, SEM, TEM, Raman, EDX, and XPS. The photothermal effect of GR-CuS will be estimated by exposing its aqueous dispersion to a 980 nm laser system and monitored its rise in temperature. Conclusion(s) or Summary: The robust NIR active agent GR-CuS has been successfully prepared. The characterization of GR-CuS will be performed using different instruments, and its photothermal effect will be estimated. References: 1. Q. Tian, F. Jiang, R. Zou, Q. Liu, Z. Chen, M. Zhu, S. Yang, J. Wang, J.Wang, J. Hu, ACS Nano 5 (2011) 9761–9771 2. R.A. Weissleder, Nat. Biotechnol. 19 (2001) 316-317 3. D. Lane, Nature Biotechnol. 24 (2006) 163-164 4. W.S. Hummers, R.E. Offeman, J. Am. Chem. Soc.80 (1958) 1339 5. G. M. Neelgund, V. N. Bliznyuk, A. Oki, Appl. Catal. B 187 (2016) 357–366.
36
