A New Scheme on Kinetics of Nickel(II)Y- L-glutamyl-L-cysteinylglycine

Department of Chemistry, Universty of Delhi, Delhi-110 007

Manuscript received 22 September 1989, revised 22 January 1990, accepted 6 February 1990

Kinetics of complexation of Ni^II by \(\gamma\)-ʟ-glutamyl-ʟ-cysteinylglycine have been investigated in the pH range 6.23-7.18, I=0.15 M KO₈ and at temperatures 25, 30, 35 and 40˚ ( \(\pm\) 0.05˚) using stopped flow spectrophotometer. The values of _kobs vary from 36.0 to 962 M^-1 s^-1 Kinetics of the complexation reaction has been studied in terms of a mechanism in which water loss from the metal ion is an important rate-determining step. Overall rate constants have been resolved into specific rate constants and there is good agreement between the calculated and experimentally obtained values for _kobs at various pH's. The values of activation parameters have been evaluated.