LAUSR

Abstract Nephropathy in tobacco smoker is postulated to be caused by nicotine (Nic) and catalyzed by various heavy metals (M(II) = Ni(II), Pb(II), and Cd(II)) contained in commercial cigarettes. Once absorbed through the lungs, these compounds will eventually be ended in the kidney, and thus, trigger various diseases. Metal chelation therapy is known as one of the efficient treatments to reduce the level of toxic metal in intoxicated patients. Here the interaction tendency of Nic and heavy metals to form complexes was investigated at a physiological condition (310.15 K and 0.15 mol·dm−3 NaCl). The stability constant of the metal-Nic complex obtained in this study shows the possible binding between these two compounds. For the simultaneous removal of heavy metals and Nic, protocatechuic acid (PCA) was used since this antioxidant is also known to be deposited in the kidney. Thus, the interaction between PCA, Nic, and heavy metals is possible. In this work, stability constant of NiPCANic, NiPCA2Nic, PbPCANic, CdPCANic, and CdPCA2Nic were determined. Species distribution diagram of the ternary system showed that MPCANic complexes could be dominantly formed in pH 7.4 system when an excess amount of antioxidant was added. This result suggests the possible usage of antioxidants for the simultaneous removal of Nic and heavy metals via the metal chelation principle.