Cell-SELEX Based Identification of an RNA Aptamer for Escherichia coli and Its Use in Various Detection Formats.
Mol Cells
; 39(11): 807-813, 2016 Nov 30.
Article
em En
| MEDLINE
| ID: mdl-27871171
ABSTRACT
Escherichia coli are important indicator organisms, used routinely for the monitoring of water and food safety. For quick, sensitive and real-time detection of E. coli we developed a 2'F modified RNA aptamer Ec3, by Cell-SELEX. The 31 nucleotide truncated Ec3 demonstrated improved binding and low nano-molar affinity to E. coli. The aptamer developed by us out-performs the commercial antibody and aptamer used for E. coli detection. Ec3(31) aptamer based E. coli detection was done using three different detection formats and the assay sensitivities were determined. Conventional Ec3(31)-biotin-streptavidin magnetic separation could detect E. coli with a limit of detection of 1.3 × 106 CFU/ml. Although, optical analytic technique, biolayer interferometry, did not improve the sensitivity of detection for whole cells, a very significant improvement in the detection was seen with the E. coli cell lysate (5 × 104 CFU/ml). Finally we developed Electrochemical Impedance Spectroscopy (EIS) gap capacitance biosensor that has detection limits of 2 × 104 CFU/mL of E. coli cells, without any labeling and signal amplification techniques. We believe that our developed method can step towards more complex and real sample application.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
RNA
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Técnicas Biossensoriais
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Escherichia coli
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Aptâmeros de Nucleotídeos
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Técnica de Seleção de Aptâmeros
Tipo de estudo:
Diagnostic_studies
Idioma:
En
Ano de publicação:
2016
Tipo de documento:
Article