摘要:
Pb(II) complexes in solution formed with different amino acids [glycine (Gly), aspartic acid (Asp), histidine (His), methionine (Met), S-methyl-cysteine (SMC) and penicillamine (Pen)], dipeptides (GlyGly, GlyVal (Val = valine), GlyMet, MetGly, GlyHis, HisGly, GlyAsp, AspGly, CysGly (Cys = cysteine), AlaCys, GlyGlu (Glu = glutamic acid), GluVal, SerGly (Ser = serine)), tripeptides (GlyGlyGly, GlyMetGly, GlyGlyMet, MetMetMet), as well as two peptidehydroxamic acids [(alanyl-alanine hydroxamic acid (AlaAlaNHOH) and N-methyl-alanyl-alanine hydroxamic acid AlaAlaN(CH3)OH)] have been studied by pH-potentiometry, H-1 NMR and ESI-MS measurements. The effects of the types and arrangements of the donor atoms on the Pb(II)-binding ability as well as on the selectivity for Pb(II) over Zn(II) were evaluated. Out of the investigated molecules, the Pb(II) binding ability of Pen is far the best, but compared to this ligand, somewhat better selectivity for Pb(II) over Zn(II) can be achieved with S-containing dipeptides. (C) 2014 Elsevier B.V. All rights reserved.