Electrochemical determination of Salmonella typhimurium by using aptamer-loaded gold nanoparticles and a composite prepared from a metal-organic framework (type UiO-67) and graphene
- 15 Downloads
An aptamer based assay is described for the determination of Salmonella typhimurium (S.typhimurium). A metal-organic framework-graphene composite of type UiO-67/GR is used as the substrate, and an aptamer-gold nanoparticles-horseradish peroxidase (Apt-AuNP-HRP) conjugate the signal amplification probe. A phosphate-terminal and partially complementary DNA (cDNA) of the aptamer is covalently bound to UiO-67/GR via the chemical complexation between phosphate and Zr-OH groups of UiO-67, and then S. typhimurium and cDNA will compete for the binding sites. The binding of Apt-AuNP-HRP to S.typhimurium leads to the formation of strong conjugates. The unbound signal probes then attach to the surface of a glassy carbon electrode via hybridization with cDNA. This generates a large current response (best measured at a potential as low as −0.02 V vs. saturated calomel electrode) under the catalytic action of HRP on the H2O2-hydroquinone system. Under the optimal conditions, the differential pulse voltammetric signal decreases linearly in the 2 × 101 – 2 × 108 cfu·mL−1 S.typhimurium concentration range, with a lower detection limit of 5 cfu·mL−1 (based on S/N = 3). The method was successfully applied to the detection of S. typhimurium in spiked milk samples.
KeywordsFoodborne pathogens Signal-off Competitive Zr-MOF In-situ synthesis Milk Differential pulse voltammetry Cyclic voltammetry Electrochemical impedance spectroscopy Horseradish peroxidase
This work was supported by the National Natural Science Foundation of China (No. 21575042).
Compliance with ethical standards
The author(s) declare that they have no competing interests.
- 3.Gonzalez-Escalona N, Brown EW, Zhang GD (2012) Development and evaluation of a multiplex real-time PCR (qPCR) assay targeting ttrRSBCA locus and invA gene for accurate detection of Salmonella spp. in fresh produce and eggs. Food Res Int 48(1):202–208. https://doi.org/10.1016/j.foodres.2012.03.009 CrossRefGoogle Scholar
- 5.Vinayaka AC, Ngo TA, Kant K, Engelsmann P, Dave VP, Shahbazi M-A, Wolff A, Bang DD (2019) Rapid detection of Salmonella enterica in food samples by a novel approach with combination of sample concentration and direct PCR. Biosens Bioelectron 129:224–230. https://doi.org/10.1016/j.bios.2018.09.078 CrossRefPubMedGoogle Scholar
- 19.Dong X, Zhao GH, Liu L, Li X, Wei Q, Cao W (2018) Ultrasensitive competitive method-based electrochemiluminescence immunosensor for diethylstilbestrol detection based on Ru(bpy)(3)(2+) as luminophor encapsulated in metal organic frameworks UiO-67. Biosens Bioelectron 110:201–206. https://doi.org/10.1016/j.bios.2018.03.066 CrossRefPubMedGoogle Scholar
- 23.Wang X, Wu M, Tang WR, Zhu Y, Wang LW, Wang QJ, He PG, Fang YZ (2013) Simultaneous electrochemical determination of ascorbic acid, dopamine and uric acid using a palladium nanoparticle/graphene/chitosan modified electrode. J Electroanal Chem 695:10–16. https://doi.org/10.1016/j.jelechem.2013.02.021 CrossRefGoogle Scholar
- 27.Dong J, Zhao H, Xu MR, Ma Q, Ai SY (2013) A label-free electrochemical impedance immunosensor based on AuNPs/PAMAM-MWCNT-chi nanocomposite modified glassy carbon electrode for detection of Salmonella typhimurium in milk. Food Chem 141(3):1980–1986. https://doi.org/10.1016/j.foodchem.2013.04.098 CrossRefPubMedGoogle Scholar
- 29.Sheikhzadeh E, Chamsaz M, Turner APF, Jager EWH, Beni V (2016) Label-free impedimetric biosensor for Salmonella typhimurium detection based on poly pyrrole-co-3-carboxyl-pyrrole copolymer supported aptamer. Biosens Bioelectron 80:194–200. https://doi.org/10.1016/j.bios.2016.01.057 CrossRefPubMedGoogle Scholar
- 30.Jia F, Duan N, Wu SJ, Dai RT, Wang ZP, Li XM (2016) Impedimetric Salmonella aptasensor using a glassy carbon electrode modified with an electrodeposited composite consisting of reduced graphene oxide and carbon nanotubes. Microchim Acta 183(1):337–344. https://doi.org/10.1007/s00604-015-1649-7 CrossRefGoogle Scholar