DETERMINATION OF PLATINUM IN PROTEIN-BOUND COOP AND DBP BY INDUCTIVELY-COUPLED PLASMA OPTICAL-EMISSION SPECTROMETRY AND ELECTROTHERMAL ATOMIC-ABSORPTION SPECTROMETRY

The plasma protein binding ability of honatomethyl)amino]acetato(2-)-O -1,N'}platinum(II) (DBP), a tumour-inhibiting platinum phosphonato com pound with osteotropic properties, was compared with that of the well established anticancer drug cisplatin (CDDP). The separation of the pl asma protein-platinum adducts was performed by a fractionated ultrafil tration experiment. The platinum levels in the protein fraction and th e ultrafiltrate of the blood plasma were detected with an echelle-base d ICP-OES system with an ultrasonic nebulizer (USN) and by ETAAS with Zeeman-effect background correction. The over-all performance of ETAAS was better than that of ICP-OES. Owing to strong, protein-induced mat rix effects in the USN, the ICP-OES measurements resulted in lower pla tinum levels in the protein fraction of blood In the determination of platinum in the ultrafiltrate, both systems showed good performance. I n comparison with CDDP, DBP shows a significant tendency to bind to pl asma proteins of lower molecular mass.