Point-of-Care Testing – Biosensor for Norepinephrine Determination

An useful electrochemical sensing approach was developed for norepinephrine (NE) detection based on semiconducting polymer (9-nonyl-2,7-di(selenophen-2-yl)-9H-carbazole) and laccase modified platinum electrode (Pt). The miniature Pt biosensor was designed and constructed via the immobilization of laccase in an electroactive layer of the electrode coated with thin polymeric film. This sensing arrangement utilized the catalytic oxidation of NE to norepinephrine quinone. The detection process was based on the oxidation of catecholamine in the presence of enzyme – laccase. With the optimized conditions, the analytical performance demonstrated selectivity in a wide linear range (0.1–200x10-6 M) with a detection limit of 240 nM and a quantification limit of 365 nM. Moreover, the method was successfully applied for selective NE determination in the presence of interfering substances