Probing interactions between exogenous metal/metalloid compounds and endogenous constituents by HPLC/LC-ICP-AES.

摘要

To better understand the biochemical fate of exogenous metal/metalloid compounds, their interactions with endogenous constituents were investigated using two chromatography-based approaches, which employed an inductively coupled plasma atomic emission spectrometer (ICP-AES) as an element specific detector. Using reversed-phase high performance liquid chromatography (RP-HPLC) coupled to an ICP-AES, an investigation of the competitive interactions between individual toxic metals (Cd2+, Hg2+, and CH3Hg +) and the low molecular weight thiols, glutathione and cysteine, revealed that each of these metals display markedly different coordination chemistry under simulated physiological conditions. In addition, the interaction of arsenobetaine, an organoarsenic compound commonly found in seafood, with blood plasma proteins was studied in vitro using size exclusion chromatography (SEC) coupled to an ICP-AES. Remarkably, arsenobetaine did not interact with any blood plasma proteins. Cumulatively, these experiments demonstrate the applicability of the HPLC/SEC-ICP-AES approaches in terms of investigating health-relevant interactions of toxic metal/metalloid compounds with endogenous constituents.