Label-free, PCR-free DNA Hybridization Detection of Escherichia coli O157 : H7 Based on Electrochemical Nanobiosensor
| Autor: | Mohammad Ebrahim Minaei, Mostafa Najafi, Hossein Honari, Mojtaba Saadati |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
Detection limit
Chromatography Oligonucleotide DNA–DNA hybridization Hybridization probe 010401 analytical chemistry Analytical chemistry 02 engineering and technology 021001 nanoscience & nanotechnology medicine.disease_cause 01 natural sciences 0104 chemical sciences Analytical Chemistry Dielectric spectroscopy chemistry.chemical_compound chemistry Electrochemistry medicine 0210 nano-technology Escherichia coli Biosensor DNA |
| Zdroj: | Electroanalysis. 28:2582-2589 |
| ISSN: | 1040-0397 |
| DOI: | 10.1002/elan.201600198 |
| Popis: | A simple and sensitive nanobiosensor was developed for diagnosing label-free, PCR-free of rfbE gene in Escherichia coli O157 : H7 real sample. The Au nanoparticles modified electrode (AunanoME) was prepared by electrodeposition technique. The single-stranded DNA probes were immobilized through the chemisorptions process on AunanoME (ssDNA/AunanoME). Electrochemical impedance spectroscopy (EIS) technique has been used to investigate the hybridization and sensing properties. Using electrochemical impedance spectroscopy (EIS) technique, the charge-transfer resistance (Rct) values were raised by immobilization of the DNA probe and after the hybridization with the complementary oligonucleotide for ssDNA/Au electrode from 2.81±0.1 to 7.62±0.2 kΩ and for ssDNA/AunanoME from 2.58±0.1 to 9.95±0.2 kΩ. The results showed that the immobilization and hybridization of DNA on the AunanoME increases effectively the nanobiosensor response compared with the Au bare electrode. In addition, the electrochemical DNA biosensor showed a good selectivity toward the detection of the complementary oligonucleotides of the rfbE gene of E. coli O157. The nanobiosensor response showed a linear dynamic range 1.0×10−13 to 1.0×10−6 mol L−1 with a detection limit of 9.1×10−14 mol L−1 and was able to detect E. coli O157 : H7 real sample corresponding to 102 cells per ml. Our results suggest that, the nanobiosensor is promising for environmental and clinical applications. |
| Databáze: | OpenAIRE |
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