Characterization of an Amperometric Biosensor for the Determination of Biogenic Amines in Flow Injection Analysis

Abstract

An amperometric biosensor using pea seedling amine oxidase (PSAO) as molecular recognition element for the determination of biogenic amines was characterized in flow injection analysis (FIA). All measurements were performed with Sørensen phosphate buffer 66 mM, pH 7.5 as mobile phase. As working electrode a bulk electrode made of carbon paste modified with manganese dioxide as mediator was used. PSAO was immobilized with a Nafion® containing film which displayed unspecific entrapment of the bio-component. With its net-like structure the film provided high biocompatibility and excellent fixation properties even in permanent flow. The enzymatically produced hydrogen peroxide was chosen as electrochemical measuring agent and the working potential was fixed at +400 mV vs. Ag/AgCl. Several biogenic amines (BAs) were tested as substrates. Putrescine, cadaverine and tyramine are marker substances for food freshness and were well detected by the biosensing FIA system. A linear correlation from 5.0 – 100.0 μg/mL was shown for cadaverine and putrescine and from 25.0 –1000.0 μg/mL for tyramine. The limit of detection (LOD) was determined to be 1.1 μg/mL for putrescine and 2.2 μg/mL for cadaverine. For tyramine the LOD was measured to be 6.2 μg/mL. The application of the biosensing FIA system for the detection of biogenic amines was successfully tested in chicken meat samples.