CHEMILUMINOMETRIC HYDROGEN-PEROXIDE SENSOR FOR FLOW-INJECTION ANALYSIS

A chemiluminometric hydrogen peroxide sensor was developed for fast flow injection analysis. Different peroxidases were covalently immobilized on affinity membranes and compared with respect to the catalytic luminol oxidation. A photomultiplier tube is connected with a fibre bundle to the flow cell. The small cell volume of 5-10 mul allows sampling rates between 90 and 200/h, depending on the flow rate. The highest sensitivity and the best long-term stability can be achieved with microbial peroxidase. Hydrogen peroxide can be determined in the range between 10(-3) and 10(-8) mol/l with a precision of < 3% (n = 6, alpha = 0.05). The operational stability of the sensor is longer than 10 weeks.