Abstract
A simple, rapid, and automated assay for hydrogen peroxide in pharmaceutical samples was developed by combining the multicommutation system with a chemiluminescence (CL) detector. The detection was performed using a spiral flow‐cell reactor made from polyethylene tubing that was positioned in front of a photodiode. It allows the rapid mixing of CL reagent and analyte and simultaneous detection of the emitted light. The chemiluminescence was based on the reaction of luminol with hydrogen peroxide catalyzed by hexacyanoferrate(III).
The feasibility of the flow system was ascertained by analyzing a set of pharmaceutical samples. A linear response within the range of 2.2–210 µmol l−1 H2O2 with a LD of 1.8 µmol l−1 H2O2 and coefficient of variations smaller than 0.8% for 1.0×10−5 mol l−1 and 6.8×10−5 mol l−1 hydrogen peroxide solutions (n=10) were obtained. Reagents consumption of 90 µg of luminol and 0.7 mg of hexacyanoferrate(III) per determination and sampling rate of 200 samples per hour were also achieved.
The authors acknowledge fellowships and the financial support from Brazilian agencies: FAPESP (Fundação de Amparo à Pesquisa do Estado de São Paulo) and CNPq (Conselho Nacional de Desenvolvimento Científico e Tecnológico).