Ru(II) Oxygen Sensors for Co(III) Complexes and Amphotericin B Antifungal Activity Detection by Phosphorescence Optical Respirometry

oleh: Katarzyna Turecka, Agnieszka Chylewska, Aleksandra M. Dąbrowska, Rafał Hałasa, Czesława Orlewska, Krzysztof Waleron

Format: Article
Diterbitkan: MDPI AG 2023-05-01

Deskripsi

The measurement of oxygen consumption is an important element in the understanding of an organism’s metabolic state. Oxygen is also a phosphorescence quencher, which allows the evaluation of phosphorescence emitted by oxygen sensors. Two Ru(II)-based oxygen-sensitive sensors were used to study the effect of chemical compounds [(<b>1</b>) = [CoCl<sub>2</sub>(dap)<sub>2</sub>]Cl, and (<b>2</b>) = [CoCl<sub>2</sub>(en)<sub>2</sub>]Cl (AmB = amphotericin B) against reference and clinical strains of <i>Candida albicans</i>. The <i>tris</i>-[(4,7-diphenyl-1,10-phenanthroline)ruthenium(II)] chloride ([Ru(DPP)<sub>3</sub>]Cl<sub>2</sub>) (Box) adsorbed onto the Davisil<sup>TM</sup> silica gel was embedded in the silicone rubber Lactite NuvaSil<sup>®</sup> 5091 and the coating on the bottom of 96-well plates. The water-soluble oxygen sensor (BsOx = <i>tris</i>-[(4,7-diphenyl-1,10-phenanthrolinedisulphonic acid disodium)ruthenium(II)] chloride ‘x’ hydrate = {Ru[DPP(SO<sub>3</sub>Na)<sub>2</sub>]<sub>3</sub>}Cl<sub>2</sub> = water molecules were omitted in the BsOx formula) was synthesized and characterized by RP-UHPLC, LCMS, MALDI, elemental analysis, ATR, UV-Vis, <sup>1</sup>H NMR, and TG/IR techniques. The microbiological studies were performed in the environment of RPMI broth and blood serum. Both Ru(II)-based sensors turned out to be useful in the study of the activity of Co(III) complexes and the commercial antifungal drug amphotericin B. In addition, a new activity of the oxygen sensor, the soluble Ru(II) complex BsOx, was demonstrated, which is a mixture with amphotericin B that caused a significant increase in its antifungal activity. Thus, it is also possible to demonstrate the synergistic effect of compounds active against the microorganisms under study.