Use of a peroxidase reactor in flow injection analysis for the determination of chloramine and the inhibition kinetics Original Research Article

A method for the determination of chloramine using a flow injection peroxidase reactor based on the inhibition reaction of the enzyme is developed. The immobilisation of the horseradish peroxidase is performed on the commercial polymer carrier VA Epoxy Biosynth. The peroxidase activity is detected photometrically based on the dehydration of the dye 2,2′-azino-di-[3-ethylenebenzthiazoline-6-sulphonate] (ABTS). The calibration of the method gives a linear concentration range from 0.026 to 1.04 mmol l−1 (SDn=3=below 5%). The detection limit was calculated to 26 μmol l−1. A mixture out of competitive and non-competitive inhibition was analysed based on the Lineweaver–Burk plots.