Novel Competitive Voltammetric Aptasensor Based on Electrospun Carbon Nanofibers-Gold Nanoparticles Modified Graphite Electrode for Salmonella Enterica Serovar Detection Publisher



Fathi S¹ ; Saber R^{1, 2} ; Adabi M¹ ; Rasouli R¹ ; Douraghi M³ ; Morshedi M⁴ ; Faridmajidi R¹ Show Affiliations
Source: Biointerface Research in Applied Chemistry Published:2021

Abstract

Salmonella enterica is considered one of the most common bacterial agent causes of acute gastroenteritis and foodborne illness in humans worldwide. Antibiotic-resistant is considered as a major problem in Salmonella enterica Serovar. This study introduces a new simple and sensitive aptasensor based on chitosan (Chi)-electrospun carbon nanofibers (CNF) /gold nanoparticles (GNPs) decorated pencil graphite electrode (GE) as a novel platform for electrochemical detection of Salmonella enterica Serovar. A Salmonella-specific recognition aptamer ssDNA sequence was used in the development of this voltammetric biosensor. Electrochemical behaviors of electrodes; unmodified GE, CNF-Chi/GE, GNPs/CNF-Chi/GE, GNPs/CNF-Chi/GEs linked with the aptamer were studied by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). After the optimization of experimental conditions (e.g., CNF concentration, pH, and incubation time), electrochemical detection of Salmonella was performed via differential pulse voltammetry (DPV) in methylene blue solution. The designed aptasensor exhibited a linear range of 10 to 105 (CFU/mL) with the limit of detection (LOD) 1.223 (Cfu/mL) for Salmonella. This aptasensor displayed excellent selectivity and remarkable sensitivity in terms of the detection of Salmonella enterica even in the real samples as compared to the polymerase chain reaction (PCR) technique. The constructed aptasensor is a highly sensitive sensor for the detection of Salmonella enterica and also can be tailored for various other targets. © 2020 by the authors.