Abstract
A rapid and sensitive analytical method was developed to detect pathogenic bacteria which combined magnetic enrichment, fluorescence labeling with polyethylene glycol (PEG) magnetophoretic chromatography. As pathogenic bacteria usually exist in complex matrixes at low concentration, an efficient enrichment is essential for diagnosis. In order to capture series types of pathogenic bacteria in samples, amino-modified magnetic nanoparticles (Fe3O4@SiO2-NH2) were prepared for efficient enrichment by the electrostatic interaction with pathogenic bacteria. It was shown that the capture efficiency reached up to 95.4% for Escherichia coli (E. coli). Furthermore, quantitative analysis of the bacteria was achieved by using acridine orange (AO) as a fluorescence probe for the captured E. coli due to its ability of staining series types of bacteria and rapid labeling. In order to remove the free magnetic nanoparticles and redundant fluorescent reagent, the labeled suspension was poured into a PEG separation column and was separated by applying an external magnetic field. The presence of 100 cfu mL−1 E. coli could be detected for semi-quantitative analysis by observing the separation column with the naked eye, and the concentration could be further evaluated by fluorescence detection. All the above processes were finished within 80 min. It was demonstrated that a good linear relationship existed between the fluorescence intensity and the concentration of E. coli ranging from 102 to 106 cfu mL−1, with a detection limit of 100 cfu mL−1 when E. coli acted as target bacteria. The recovery rate of E. coli was 93.6∼102.0% in tap water and cooked meat samples, and the RSD was lower than 7% (n = 6); the result coincided with the conventional plate count method.
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References
Delalibera I, Humber RA, Hajek AE. Preservation of in vitro cultures of the mite pathogenic fungus Neozygites tanajoae. Can J Microbiol. 2004;50(8):579–86.
Seurinck S, Verstraete W, Siciliano SD. Microbial source tracking for identification of fecal pollution. Rev Environ Sci Biotechnol. 2005;4(1):19–37.
Jain S, Chattopadhyay S, Jackeray R, Abid CKVZ, Kohli GS, Singh H. Highly sensitive detection of Salmonella typhi using surface aminated polycarbonate membrane enhanced-ELISA. Biosens Bioelectron. 2012;31(1):37–43.
Opet NJ, Levin RE. Efficacy of coating activated carbon with milk proteins to prevent binding of bacterial cells from foods for PCR detection. J Microbiol Methods. 2013;94(2):69–72.
Rohde A, Hammerl JA, Appel B, Dieckmann R, Al DS. FISHing for bacteria in food—a promising tool for the reliable detection of pathogenic bacteria? Food Microbiol. 2015;46:395–7.
Hu R, Yin Z, Zeng Y, Zhang J, Liu H, Shao Y, et al. A novel biosensor for Escherichia coli O157:H7 based on fluorescein-releasable biolabels. Biosens Bioelectron. 2016;78:31–6.
Zhu M, Liu W, Liu H, Liao Y, Wei J, Zhou X, et al. Construction of Fe3O4/vancomycin/PEG magnetic Nanocarrier for highly efficient pathogen enrichment and gene sensing. ACS Appl Mater Inter. 2015;7(23):12873–81.
Liébana S, Spricigo DA, Cortés MP, Barbé J, Llagostera M, Alegret S, et al. Phagomagnetic separation and electrochemical magneto-genosensing of pathogenic bacteria. Anal Chem. 2013;85(6):3079–86.
Ravindranath SP, Mauer LJ, Deb-Roy C, Irudayaraj J. Biofunctionalized magnetic nanoparticle integrated mid-infrared pathogen sensor for food matrixes. Anal Chem. 2009;81(8):2840–6.
Shan Z, Wu Q, Wang X, Zhou Z, Oakes KD, Zhang X, et al. Bacteria capture, lysate clearance, and plasmid DNA extraction using pH-sensitive multifunctional magnetic nanoparticles. Anal Biochem. 2010;398(1):120–2.
Huang Y, Wang Y, Yan X. Amine-functionalized magnetic nanoparticles for rapid capture and removal of bacterial pathogens. Environ Sci Technol. 2010;44(20):7908–13.
Zhan S, Yang Y, Shen Z, Shan J, Li Y, Yang S, et al. Efficient removal of pathogenic bacteria and viruses by multifunctional amine-modified magnetic nanoparticles. J Hazard Mater. 2014;274:115–23.
Cheng D, Yu M, Fu F, Han W, Li G, Xie J, et al. Dual recognition strategy for specific and sensitive detection of bacteria using aptamer-coated magnetic beads and antibiotic-capped gold nanoclusters. Anal Chem. 2016;88(1):820–5.
Guo P, Tang M, Hong S, Yu X, Pang D, Zhang Z. Combination of dynamic magnetophoretic separation and stationary magnetic trap for highly sensitive and selective detection of Salmonella typhimurium in complex matrix. Biosens Bioelectron. 2015;74:628–36.
Song E, Han W, Li J, Jiang Y, Cheng D, Song Y, et al. Magnetic-encoded fluorescent multifunctional nanospheres for simultaneous multicomponent analysis. Anal Chem. 2014;86(19):9434–42.
Ondera TJ, Hamme AT. Magnetic-optical nanohybrids for targeted detection, separation, and photothermal ablation of drug-resistant pathogens. Analyst. 2015;140(23):7902–11.
Bhaisare ML, Gedda G, Khan MS, Wu H. Fluorimetric detection of pathogenic bacteria using magnetic carbon dots. Anal Chem Acta. 2016;920:63–71.
Wen C, Hu J, Zhang Z, Tian Z, Ou G, Liao Y, et al. One-step sensitive detection of Salmonella typhimurium by coupling magnetic capture and fluorescence identification with functional nanospheres. Anal Chem. 2013;85(2):1223–30.
Kwon D, Lee S, Ahn MM, Kang IS, Park K, Jeon S. Colorimetric detection of pathogenic bacteria using platinum-coated magnetic nanoparticle clusters and magnetophoretic chromatography. Anal Chem Acta. 2015;883:61–6.
Kwon D, Joo J, Lee J, Park K, Jeon S. Magnetophoretic chromatography for the detection of pathogenic bacteria with the naked eye. Anal Chem. 2013;85(15):7594–8.
Jiang Y, Xu Y, Wang R, Zhao B, Zhang X, Zhao H. Detection of Staphylococcus aureus using acridine orange-doped silica nanoparticles as a fluorescent label. RSC Adv. 2015;5:54338–44.
Wang J, Zheng S, Shao Y, Liu J, Xu Z, Zhu D. Amino-functionalized Fe(3)O(4)@SiO(2) core-shell magnetic nanomaterial as a novel adsorbent for aqueous heavy metals removal. J Colloid Interface Sci. 2010;349(1):293–9.
Acknowledgements
The work described was supported by National Natural Science Foundation of China (No.21375156), High Technology Research and Development Program of China (Ministry of Science and Technology 863 Plan) (No.2015AA021104), Frontier Research Key Projects of Chongqing Science and Technology Committee (cstc2015jcyjBX0010), Scientific and Technical Innovation Projects for People’s Livelihood of Chongqing Science and Technology Committee, (cstc2015shmszx00014), Fundamental Research Funds for the Central Universities (No.106112015CDJZR225512), and Benefit Projects for People’s Livelihood by Science and Technology (cstc2015jcsf8001).
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Che, Y., Xu, Y., Wang, R. et al. Rapid fluorescence detection of pathogenic bacteria using magnetic enrichment technique combined with magnetophoretic chromatography. Anal Bioanal Chem 409, 4709–4718 (2017). https://doi.org/10.1007/s00216-017-0415-6
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DOI: https://doi.org/10.1007/s00216-017-0415-6