Electrochemical Characterization of Auranofin in Aqueous Media

Detection of antibiotic compounds in various media is necessary in solving the public health crisis of antibiotic resistance[1]. Auranofin (AF) is a repurposed antibiotic first used as an antirheumatic in the 1950s. It is useful against various bacteria, fungi, virus infections and cancers either by itself or synergistically with other antibiotics[2–5]. AF is composed of aurothioglucose and phosphine moieties, and therefore, has lipophilic and hydrophilic properties, making its characterization in aqueous media particularly difficult. In the presented study, electrochemistry was employed to characterize and detect AF in aqueous solutions using modified glassy carbon electrodes (GCEs), coated with Carbon Black (CB). CB coating was optimized, oxidation and reduction potentials were identified, and pH dependence, as well as Limits of Detection (LOD) and Quantification (LOQ) were determined. Interferences with ions and other antibiotics was studies and are important factors for the detection of AF in the environment. This study reports on the sensitivity, stability, and selectivity of the CB-GCE sensors, proving useful for future field detection and/or bioelectrochemical investigations. CITATIONS [1] M.R. Islam, S. Kuss, F. Schweizer, Characterization of Antibiotic Compounds By Electrochemistry, ECS Meeting Abstracts. MA2020-01 (2020). https://doi.org/10.1149/ma2020-01442531mtgabs. [2] R. Díez-Martínez, E. García-Fernández, M. Manzano, Á. Martínez, M. Domenech, M. Vallet-Regí, P. García, Auranofin-loaded nanoparticles as a new therapeutic tool to fight streptococcal infections, Scientific Reports. 6 (2016). https://doi.org/10.1038/srep19525. [3] K.J. Habermann, L. Grünewald, S. van Wijk, S. Fulda, Targeting redox homeostasis in rhabdomyosarcoma cells: GSH-depleting agents enhance auranofin-induced cell death, Cell Death & Disease. 8 (2017). https://doi.org/10.1038/cddis.2017.412. [4] E. v. Capparelli, R. Bricker-Ford, M.J. Rogers, J.H. McKerrow, S.L. Reed, Phase I clinical trial results of auranofin, a novel antiparasitic agent, Antimicrobial Agents and Chemotherapy. 61 (2017). https://doi.org/10.1128/AAC.01947-16. [5] T. Onodera, I. Momose, M. Kawada, Potential anticancer activity of auranofin, Chemical and Pharmaceutical Bulletin. 67 (2019). https://doi.org/10.1248/cpb.c18-00767.