Ru Complexes and Amphotericin B Antifungal Activity Detection by Phosphorescence Optical Respirometry

• Published in: International journal of molecular sciences Vol. 24; no. 10
• Main Authors: Turecka, Katarzyna, Chylewska, Agnieszka, Dąbrowska, Aleksandra M, Hałasa, Rafał, Orlewska, Czesława, Waleron, Krzysztof
• Format: Journal Article
• Language: English
• Published: MDPI AG 01.05.2023
• Subjects: Amphotericin B; Antiparasitic agents; Biological products; Cells; Sensors; Poland
• ISSN: 1422-0067; 1422-0067
• DOI: 10.3390/ijms24108744

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 [(1) = [CoCl[sub.2](dap)[sub.2]]Cl, and (2) = [CoCl[sub.2](en)[sub.2]]Cl (AmB = amphotericin B) against reference and clinical strains of Candida albicans. The tris-[(4,7-diphenyl-1,10-phenanthroline)ruthenium(II)] chloride ([Ru(DPP)[sub.3]]Cl[sub.2]) (Box) adsorbed onto the Davisil[sup.TM] silica gel was embedded in the silicone rubber Lactite NuvaSil[sup.®] 5091 and the coating on the bottom of 96-well plates. The water-soluble oxygen sensor (BsOx = tris-[(4,7-diphenyl-1,10-phenanthrolinedisulphonic acid disodium)ruthenium(II)] chloride 'x' hydrate = {Ru[DPP(SO[sub.3]Na)[sub.2]][sub.3]}Cl[sub.2] = water molecules were omitted in the BsOx formula) was synthesized and characterized by RP-UHPLC, LCMS, MALDI, elemental analysis, ATR, UV-Vis, [sup.1]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.