Abstract

The palladium [Pd⁺²] catalysed electron transfer reaction between glutathione (reduced) (GSH) and pyridinium chlorochromate (PCC) has been studied spectrophotometrically over the range 2.00≤10³ [GSH] ≤ 6.00, 0.01 ≤ [H⁺] ≤ 0.03 mol dm^-3, 2.83≤10⁵[Pd ⁺²] = 14.15 and 20 ⁰C ≤ t ≤40 ⁰C. The rate of reaction was found to increase with the increase in [GSH]_T, [H+]_T and [Pd⁺²]. The reaction was found to exhibit first order dependence in [GSH]_T, [H+]_T and [Pd⁺²]_T. The ΔH^≠ (kJ/mol) and ΔS^≠ (JK^-1 mol^-1) for the electron transfer reaction were found to be -27.7 and -243.9. The product of the reaction was found to be glutathione disulfide (GSSG) as indicated by infrared spectrum. The negative values of activation parameters favour the formation of the ordered transition state.

Keywords

Palladium, Glutathione (Reduced), Pyridinium chlorochromate and Electron transfer