SOL-GEL HORSERADISH-PEROXIDASE BIOSENSOR FOR HYDROGEN-PEROXIDE DETECTION BY CHEMILUMINESCENCE

Horseradish peroxidase (HRP) was immobilized by microencapsulation in sol-gel crystals derived from tetramethyl orthosilicate. A sol-gel bio sensor based on the chemiluminescence reaction of the hydrogen peroxid e-luminol-HRP system was developed. Calibration plots for hydrogen per oxide have been established by chemiluminescence measurements in a cuv ette and through an optical fibre modified at its end with the immobil ized HRP gel. The detection limit was 6.7 x 10(-4) M and the linear ra nge was 0.1-3.0 mM. The relative standard deviation was 7.1% (n=4). Th is method was applied to hydrogen peroxide determination in disinfecta nt solutions for contact lenses. (C) 1998 Elsevier Science B.V.