Author(s): Wang, L (Wang, Lei); Huo, XT (Huo, Xiaoting); Qi, WZ (Qi, Wuzhen); Xia, ZZL (Xia, Zengzilu); Li, YT (Li, Yuntao); Lin, JH (Lin, Jianhan)

Source: TALANTA Volume: 211 Article Number: 120715 DOI: 10.1016/j.talanta.2020.120715 Published: MAY 1 2020

Abstract: Rapid detection of foodborne pathogens is crucial to prevent the outbreaks of foodborne illnesses. In this study, a sensitive electrochemical aptasensor was developed using aptamer coated gold interdigitated microelectrode for target capture and impedance measurement, and antibody modified nickel nanowires (NiNWs) for target separation and impedance amplification. First, the interdigitated microelectrode was modified with the biotinylated aptamers against Salmonella typhimurium through electrostatic absorption of streptavidin onto the microelectrode and streptavidin-biotin binding. Then, the target Salmonella cells were magnetically separated and concentrated using the NiNWs modified with the anti Salmonella typhimurium antibodies to form the bacteria-NiNW complexes, and incubated on the microelectrode to form the aptamer-bacteria-NiNW complexes. After an external arc magnetic field was developed and applied to control the NiNWs to form conductive NiNW bridges across the microelectrode, the enhanced impedance change of the microelectrode was measured and used to determine the amount of target bacteria. This electrochemical aptasensor was able to quantitatively detect Salmonella ranging from 10(2) to 10(6) CFU/mL in 2 h with the detection limit of 80 CFU/mL. The mean recovery for the spiked chicken samples was 103.2%.

Accession Number: WOS:000518708300028

PubMed ID: 32070611

ISSN: 0039-9140

eISSN: 1873-3573

Full Text: https://www.sciencedirect.com/science/article/pii/S0039914020300060?via%3Dihub