Pathogen detection by core-shell type aptamer-magnetic preconcentration coupled to real-time PCR.
Anal Biochem
; 447: 119-25, 2014 Feb 15.
Article
em En
| MEDLINE
| ID: mdl-24291643
ABSTRACT
The presence of pathogenic bacteria is a major health risk factor in food samples and the commercial food supply chain is susceptible to bacterial contamination. Thus, rapid and sensitive identification methods are in demand for the food industry. Quantitative polymerase chain reaction (PCR) is one of the reliable specific methods with reasonably fast assay times. However, many constituents in food samples interfere with PCR, resulting in false results and thus hindering the usability of the method. Therefore, we aimed to develop an aptamer-based magnetic separation system as a sample preparation method for subsequent identification and quantification of the contaminant bacteria by real-time PCR. To achieve this goal, magnetic beads were prepared via suspension polymerization and grafted with glycidylmethacrylate (GMA) brushes that were modified into high quantities of amino groups. The magnetic beads were decorated with two different aptamer sequences binding specifically to Escherichia coli or Salmonella typhimurium. The results showed that even 1.0% milk inhibited PCR, but our magnetic affinity system capture of bacteria from 100% milk samples allowed accurate determination of bacterial contamination at less than 2.0 h with limit of detection around 100 CFU/mL for both bacteria in spiked-milk samples.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Salmonella typhi
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Escherichia coli O157
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Aptâmeros de Nucleotídeos
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Métodos Analíticos de Preparação de Amostras
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Reação em Cadeia da Polimerase em Tempo Real
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Fenômenos Magnéticos
Tipo de estudo:
Diagnostic_studies
/
Prognostic_studies
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Risk_factors_studies
Idioma:
En
Revista:
Anal Biochem
Ano de publicação:
2014
Tipo de documento:
Article