Nonenzymatic NADH‐Dependent Reduction of Keggin‐Type 12‐Tungstocobaltate(III) in Aqueous Medium

Abstract

The kinetics of the electron transfer reaction of NADH with 12-tungstocobaltate(III) has been studied over the range 5.07 ≤ 104[NADH] ≤ 15.22 mol dm-3, 7.0 ≤ pH ≤ 8.0 and 20 ≤ t ≤ 35oC in aqueous medium. The electron transfer reaction showed first-order dependence each in [NADH]Tand [12-tungstocobaltate(III)]T. The products of the reaction were found to be NAD+and 12-tungstocobaltate(II). The activation parameters ΔH#(kJ mol-1) and ΔS#(JK-1mol-1) of the electron transfer reactions were found to be 64.4±1.8 and -48.86±6.0. Negative value of ΔS#is an indicative of an ordered transition state for the electron transfer reaction.

Non enzymatic NADH-dependent reduction of Cis-[Co(en)2(H2O)2]3+ in aqueous medium

“…Compared to all, octahedral cobalt(III) complexes being substitutionally inert are the more priority. Therefore, recently redox reactions involving octahedral cobalt(III) complexes and NADH have attaracted considerable attentation [Kumari et. al.…”

Kinetics and Mechanism of Oxidation of Diclofenac Sodium by Keggin Type 12-Tungstocobalt(III) in Aqueous Medium

“…It is a well known outer sphere oxidant [7,8] and a mild oxidant. Its electron transfer reaction with ascorbic acid [9] glutathione [1]0, citric acid [11], DL-methionine [12], L-cysteine [13], NADH [14] and L-cystine [15] have been studied. In order to examine the oxidative degradation of diclofenac sodium, its oxidation reaction with the above oxidant has been studied.…”