Background: Methionine, Met, is one of the sulfur containing amino acids
required in the human body by certain biochemical reactions. Since Met is not biosynthesized
in humans, it needs to be supplied externally in diet. Met is highly susceptible to oxidation.
Objective: The oxidation of Met to its sulfone by CAB in aqueous perchloric acid medium at
323 K has been kinetically studied.
Method: Effect of varying ionic strength, solvent composition, dielectric constant has been
determined. Effect of reduction product of Chloramine-B (CAB), benzenesulfonamide, on the
reaction rate has also been investigated.
Conclusion: The experimental rate law obtained is: rate = k׀ [CAB] [H2O]. Activation
parameters have been evaluated using Arrhenius and Eyring plots. A mechanism consistent
with the observed kinetic data has been discussed. A rate law has been derived based on the