1H nmr study of the effectiveness of various thiols for removal of methylmercury from hemolyzed erythrocytes

Abstract The effectiveness of eight thiol ligands for removing methylmercury (CH 3 Hg(II)) from its glutathione and hemoglobin complexes in hemolyzed erythrocytes has been studied by 1 H nuclear magnetic resonance spectroscopy. These complexes are the predominant methylmercury species in human erythrocytes. The effectiveness was determined from the exchange-averaged chemical shift of the resonance for the proton on the α-carbon of the cysteinyl residue and from the intensity of the resonance for the methylene protons of the glycine residue of reduced glutathione (GSH), both of which provide a measure of the amount of glutathione in the CH 3 Hg(II)-complexed form. The thiol ligands were found to release GSH from its CH 3 Hg(II) complex in the order 2, 3-dimercap-tosuccinic acid > mercaptosuccinic acid > cysteine > mercaptoacetic acid > D-penicillamine > 2, 3-dimercaptopropanesulfonic acid > N -acetyl-D,L-penicillamine > D.L-homocysteine.