Investigation of the oxidation state and coordination sphere of gold-based drug candidates cultured in 2D cells by cryo-X-Ray Absorption Spe

Organometallic gold complexes bearing biphenyl and diphosphine chelating ligands of the general formula [(C^C)Au(P^P)]+ present antiproliferative activities in the submicromolar range. We could demonstrate by various techniques including mass spectrometry and cryo-XRF mapping (ESRF, LS-3136) these complexes to be stable inside lung cancer cells and to accumulate selectively in mitochondria. We apply for beamline time at FAME UHD to perform cryo-X-Ray Absorption Spectroscopy measurements on treated cancer cells with our [(C^C)Au(P^P)]+ gold complex in order to confirm its intracellular stability by the mean of the determination of the oxidation state and first coordination sphere of the gold ion. This would represent the first speciation study of gold(III) complexes inside cancer cells