An all-in-one magnetic SERS nanosensor for ratiometric detection of Escherichia coli in foods
- 29 July 2021
- journal article
- research article
- Published by Springer Science and Business Media LLC in Analytical and Bioanalytical Chemistry
- Vol. 413 (21), 5419-5426
- https://doi.org/10.1007/s00216-021-03521-2
Abstract
An all-in-one nanosensor was developed for the magnetic enrichment and ratiometric surface-enhanced Raman scattering (SERS) detection of Escherichia coli (E. coli). The all-in-one nanosensor was constructed through the chemical integration of four components into a single nanoparticle, which include a manganese ferrite nanoparticle serving as the magnetic core, a thin silver shell as the SERS substrate, a self-assembled layer of 4-mercaptobenzoic acid (MBA) molecules as the SERS internal standard, and a MBA-conjugated layer of aptamer sequences as the capture probe of E. coli. In the detection of E. coli in food, the target cells were first captured by the nanosensors and magnetically enriched in a short time of 15 min, and then the ratiometric SERS was performed through the Raman intensity ratio between two specific SERS peaks produced by the captured E. coli and the internal MBA. The pre-concentration and ratiometry enabled the nanosensor to detect E. coli with a detection limit down to 10 CFU/mL. The all-in-one nanosensor was successfully applied for the detection of E. coli in various liquid foods including milk, juice, tea, and coffee, with recoveries ranging from 89 to 110% and relative standard deviation lower than 1.7%. In comparison with the previous sandwich strategy adopted by most SERS sensors, this nanosensor endowed with an easier use and a lower cost is more sensitive and reproducible, leading to a great potential in practical applications.Keywords
Funding Information
- National Natural Science Foundation of China (31770113)
- Graduate Innovation Program of Chongqing Technology and Business University (CYS20315)
This publication has 19 references indexed in Scilit:
- Recent advances in dual recognition based surface enhanced Raman scattering for pathogenic bacteria detection: A reviewAnalytica Chimica Acta, 2021
- Bacteria Detection: From Powerful SERS to Its Advanced Compatible TechniquesAdvanced Science, 2020
- Application of surface-enhanced Raman spectroscopy in fast detection of toxic and harmful substances in foodBiosensors and Bioelectronics, 2020
- Sensitive and simultaneous detection of different pathogens by surface-enhanced Raman scattering based on aptamer and Raman reporter co-mediated gold tagsSensors and Actuators B: Chemical, 2020
- Gold Nanoparticle-Coated Starch Magnetic Beads for the Separation, Concentration, and SERS-Based Detection of E. coli O157:H7ACS Applied Materials & Interfaces, 2020
- Sensitive and specific detection of clinical bacteria via vancomycin-modified Fe3O4@Au nanoparticles and aptamer-functionalized SERS tagsJournal of Materials Chemistry B, 2018
- Rapid and sensitive detection of sodium saccharin in soft drinks by silver nanorod array SERS substratesSensors and Actuators B: Chemical, 2017
- Advanced molecular diagnostic techniques for detection of food-borne pathogens: Current applications and future challengesCritical Reviews in Food Science and Nutrition, 2017
- Raman and infra-red microspectroscopy: towards quantitative evaluation for clinical research by ratiometric analysisChemical Society Reviews, 2015
- Quantitative surface-enhanced Raman measurements with embedded internal referenceAnalytica Chimica Acta, 2015