Spectroscopic and Computational pH Study of Ni^II and Pd^II Pyrrole-Imine Chelates with Human Serum Albumin.

ABSTRACT: Human serum albumin (HSA) efficiently transports drugs in vivo: most are organic. Therefore, it is important to delineate the binding of small molecules to HSA. Here, for the first time, we show that HSA binding depends not only on the identity of the d⁸ metal ion, Ni^II or Pd^II, of their complexes with bis(pyrrole-imine), H₂PrPyrr, but on the pH level as well. Fluorescence quenching data for native and probe-bound HSA showed that sites close to Trp-214 (subdomain IIA) are targeted. The affinity constants, Ka, ranged from ~3.5 × 10³ M^-1 to ~1 × 10⁶ M^-1 at 37 °C, following the order Pd(PrPyrr) > Ni(PrPyrr) at pH levels of 4 and 7; but Ni(PrPyrr) > Pd(PrPyrr) at a pH level of 9. Ligand uptake is ent

SUBMITTER: Sookai S 

PROVIDER: S-EPMC10673405 | biostudies-literature | 2023 Nov

REPOSITORIES: biostudies-literature