Abstract
The present work reports the development of a disposable nanocomposite-based amperometric sensor for reduced nicotinamide adenine dinucleotide (NADH). To fabricate disposable electrodes, conductive carbon and silver ink were screen-printed on a polyethylene terephthalate (PET) film substrate. The surface of the working electrode was modified with gold nanoparticles (AuNPs) decorated reduced graphene oxide (rGO) and subsequently electro-polymerized with methylene blue for the determination of NADH. The nanocomposite modified electrode decreases the potential for NADH oxidation with a significant increase in the current due to the synergy between AuNP and rGO. The developed electrochemical sensor determined NADH at 0 V versus pseudo-Ag/AgCl with linear relationships from 25 µmol L−1 to 1.0 mmol L−1 and 1.0 mmol L−1 to 10 mmol L−1. The sensor exhibits a good sensitivity of 35.49 µA/mmol L−1/cm2 and a detection limit of 6.61 µmol L−1 based upon a signal-to-noise ratio of 3. Furthermore, interferences from electroactive substances such as ascorbic acid and uric acid are eliminated at an oxidation potential of 0 V. Thus, the modified electrode provides a simple, selective, disposable, and low-cost approach for the amperometric determination of NADH.
Acknowledgment
The instruments (FESEM and EDX) used in this work were supported by the Center for Research Facilities, Kyungpook National University, Daegu, Rep. Korea.
Disclosure statement
No potential conflict of interest was reported by the authors.