Sequential injection determination of D-glucose by chemiluminescence using an open tubular immobilised enzyme reactor

A sequential injection analysis system is described that incorporates a nylon tubular reactor containing immobilised glucose oxidase, allowing determination of D-glucose by means of subsequent luminol chemiluminescence detection of the hydrogen peroxide generated in the enzymatic reaction. The operating parameters were optimised by fractional factorial screening and response surface modelling. The linear range of D-glucose determination was 30–600 μM, with a detection limit of 15 μM using a photodiode detector. The sampling frequency was 54 h−1. Lower LOD (0.5 μM D-glucose) could be reached by using a PMT as the detector. Fermentation broth samples were determined and good recoveries were obtained.