Nano-sized chitosan particles based electrochemical aptasensor for sensitive detection of P. aeruginosa
In this research, a glassy carbon electrode (GCE) was modified with nano-sized chitosan particles (NC) by the drop-casting method for ultrasensitive detection of Pseudomonas aeruginosa (P. aeruginosa). NC is as a novel platform of the aptamer-based sensor (aptasensor) detection sensitively and simultaneously of P. aeruginosa. This system is based on a P. aeruginosa-binding aptamer, which is covalently connected to the surface of the GCE which has been in turn modified by the NC in order to form a sensitive layer and improve the performance of the aptasensor. In order to investigate the conductivity of the aptasensor and electrochemical properties, the electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) techniques were used. Low detection limits 3 CFU. ml-1, wide linearity 101 -107 CFU. ml-1 to the detection of P. aeruginosa and high sensitivity for the aptasensor, which are obtained in optimized conditions, have been proposed. To detect P. aeruginosa in blood serum samples, the prepared aptasensor was successfully applied. This aptasensor also showed excellent stability with satisfying electrochemical performance, reproducibility, and selectivity.