Simultaneous Interaction of Two Dissimilar Metal Ions with Tripeptide Glutathione (Reduced) in Different Aqueous Organic Solvents: An Absorption Spectral Study

摘要

The interaction of two dissimilar metal ions praseodymium(III) and Zn(II), a soft metal ion or Ca(II), a hard metal ion with tripeptide glutathione reduced (GSH) in aqueous and mixed aqueous - organic solvents has been discussed by employing absorption difference and comparative absorption spectrophotometry. The 4f-4f transition bands were analysed by linear curve analysis followed by gaussian curve analysis and various spectral parameters were computed using partial and multiple regression method. The changes in the oscillator strengths of the different 4f-4f transition and experimentally determined Judd-Ofelt parameters (T_λ) are correlated with the binding of glutathione (GSH) with Pr(III) in presence and absence of Zn(II) or Ca(II) in different aqueous - organic solvents. The variation of Slater Condon (F_k), Racah (E~k), Landespin orbit coupling (ξ_(4f)~·), nephelauxetic (β), bonding (b~(1/2)) and covalency (δ) parameters have also been calculated to support the intensity data.