Low-Cost Strategy for the Development of a Rapid Electrochemical Assay for Bacteria Detection Based on AuAg Nanoshells

Abstract

A low-cost strategy for the simple and rapid detection of bacterial cells in biological matrixes is presented herein. Escherichia coli and Salmonella typhimurium were chosen as model bacteria for the development of an electrochemical assay based on hollow AuAg nanoshells (NSs). By taking advantage of their electrocatalytic properties for the in situ generation of the electrochemical signal without the need of any other kind of reagent, substrate, or redox enzyme, high sensitivities (down to 10 2 CFU/mL) were achieved. Moreover, the recognition and discrimination of the model bacterial cells in the sample matrix was possible by relying solely on nonspecific affinity interactions between their cell walls and AuAg NSs surface, avoiding the use of expensive and fragile biological receptor. Compared to traditional, laboratorybased analytical tests available, this assay provides a promising proof-of-concept alternative that allows to obtain good sensitivities and selectivity in very short times in addition to the low cost.

An Alternative Medical Diagnosis Method: Biosensors for Virus Detection

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An Analysis Review, Detection Coronavirus Disease 2019 (COVID-19) based on Biosensor Application

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Nanomaterial-based sensors

“…Beyond this, the use of AgNPs as electrochemical label has been recently demonstrated in combination with Au. Russo et al [51] took advantage of a novel class of nanomaterial, namely hollow AuAg nanoshells (NSs), to detect E. coli and Salmonella typhimurium at a screen-printed carbon-based electrode. The determination of bacteria is due to non-specific affinity interactions between bacteria's walls and AuAg NSs surface.…”