Biosensing of naringin in marketed fruits and juices based on its interaction with DNA

Abstract

A new electrochemical biosensor is introduced to study naringin–DNA interaction and naringin detection, using a modified pencil graphite electrode (PGE). The biosensor was prepared by modification of a PGE with MWCNTs-poly dialyldimethylammonium chloride (PDDA) decorated with ds-DNA (dsDNA/PDDA-MWCNTs/PGE). Change in the oxidation signals of adenine and guanine was used as probes for the biosensor evaluation, using differential pulse voltammetry. Under the optimized conditions, naringin could be measure from 0.058 to 580.0 µg mL−1 with a limit of detection of 0.010 µg mL−1. The relative standard deviation for five measurements of 0.58 µg mL−1 naringin was found as 3.7 and 4.2 %, based on the guanine and adenine signals, respectively. The biosensor was used as a selective sensor for the determination of naringin. In addition, electrochemical impedance spectroscopy was performed to evaluate the charge-transfer resistance of the modified and unmodified PGEs. Finally, this highly stable electrochemical biosensor was used to analyze naringin contents in various citrus juices.