Chemiluminescent flow-through sensor for hydrogen peroxide based on sol¯gel immobilized hemoglobin as catalyst

A novel chemiluminescence (CL) flow-through sensor for hydrogen peroxide is described. It is prepared by immobilizing hemoglobin (Hb) with the sol¯gel method on the flow cell, and by electrostatically immobilizing luminol on strongly basic anionexchange resin. Hydrogen peroxide is sensed by the CL reaction with Hb sensitive membrane and luminol bleeding from the ion-exchange column with immobilized luminol by hydrolysis. The calibration graph is linear in the range of 6×10-5 to 4×10-7 mol l-1 with a detection limit of 1.3×10-7 mol l-1 (3sigma). A complete analysis could be performed in 1 min with a relative standard deviation of 1.7% for 5×10-6 mol l-1 H2O2 (n=9). The sensor has been applied successfully to the determination of hydrogen peroxide in rainwater.