Poly(allylamine hydrochloride) modified screen-printed carbon electrode for sensitive and selective detection of NADH

A screen-printed electrode (SPE) modified with poly(allylamine hydrochloride) (PAH) for electrochemical detection of NADH is described. FT-IR spectrum confirms the presence of a positively charged PAH SPE that was exploited to accumulate the NADH on the electrode surface for a faster electrochemical detection of this analyte. A wide response range was achieved in amperometry, at an applied potential of +0.6 V, from 0.01 to 5 mM, with a detection limit of 0.22 μM. Differential pulse voltammetry allowed selective detection of NADH in presence of ascorbic acid. This approach provides a simple and effective way to detect low amounts of NADH with potential application in dehydrogenase-based biosensors.