The second-generation Pt II anticancer drug carboplatin is here shown to react with carbonate, which is present in blood, interstitial fluid, cytosol, and culture medium, to produce platinum-carbonato and -hydroxo complexes. Using [ 1H- 15N] HSQC NMR and 15N-labeled carboplatin, we observe that cis-[Pt(CBDCA-O)(OH)(NH 3) 2] -, cis-[Pt(OH) 2(NH 3) 2], cis-[Pt(CO 3)(OH)(NH 3) 2] -, and what may be cis-[Pt(CO 3)(NH 3) 2] are produced when 1 is allowed to react in 23.8 mM carbonate buffer. When 15N-labeled carboplatin is allowed to react in 0.5 M carbonate buffer, these platinum species, as well as other hydroxo and carbonato species, some of which may be dinuclear complexes, are produced. Furthermore, we show that the carbonato species cis-[Pt(CO 3)(OH) (NH 3) 2] - is also produced when cisplatin is allowed to react in carbonate buffer. The study outlines the conditions under which carboplatin and cisplatin form carbonato and aqua/hydroxo species in carbonate media.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Inorganic Chemistry