title: Cell-SELEX Based Identification of an RNA Aptamer forEscherichia coliand Its Use in Various Detection Formats.
abstract: Escherichia coliare important indicator organisms, used routinely for the monitoring of water and food safety. For quick, sensitive and real-time detection ofE. coliwe developed a 2'F modified RNA aptamer Ec3, by Cell-SELEX. The 31 nucleotide truncated Ec3 demonstrated improved binding and low nano-molar affinity toE. coli. The aptamer developed by us out-performs the commercial antibody and aptamer used forE.colidetection. Ec3(31) aptamer basedE. colidetection was done using three different detection formats and the assay sensitivities were determined. Conventional Ec3(31)-biotin-streptavidin magnetic separation could detectE. coliwith a limit of detection of 1.3 × 106CFU/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 theE. colicell lysate (5 × 104CFU/ml). Finally we developed Electrochemical Impedance Spectroscopy (EIS) gap capacitance biosensor that has detection limits of 2 × 104CFU/mL ofE. colicells, without any labeling and signal amplification techniques. We believe that our developed method can step towards more complex and real sample application.
authors.affiliation: Global Research Laboratory (GRL) for RNAi Medicine, Department of Chemistry, Sungkyunkwan University (SKKU), Suwon 16419, Korea.
authors.forename: Pooja
authors.initials: P
authors.lastname: Dua
authors.affiliation: Department of Bioengineering, Dongguk University, Seoul 04620, Korea.
authors.forename: Shuo
authors.initials: S
authors.lastname: Ren
authors.affiliation: Department of Bioengineering, Dongguk University, Seoul 04620, Korea.
authors.forename: Sang Wook
authors.initials: SW
authors.lastname: Lee
authors.affiliation: Global Research Laboratory (GRL) for RNAi Medicine, Department of Chemistry, Sungkyunkwan University (SKKU), Suwon 16419, Korea.
authors.forename: Joon-Ki
authors.initials: JK
authors.lastname: Kim
authors.affiliation: Global Research Laboratory (GRL) for RNAi Medicine, Department of Chemistry, Sungkyunkwan University (SKKU), Suwon 16419, Korea.
authors.forename: Hye-Su
authors.initials: HS
authors.lastname: Shin
authors.affiliation: Department of Biomedical Engineering and School of Mechanical Engineering, Inje University, Gimhae 50834, Korea.
authors.forename: Ok-Chan
authors.initials: OC
authors.lastname: Jeong
authors.affiliation: Department of Bioengineering, Dongguk University, Seoul 04620, Korea.
authors.forename: Soyoun
authors.initials: S
authors.lastname: Kim
authors.affiliation: Global Research Laboratory (GRL) for RNAi Medicine, Department of Chemistry, Sungkyunkwan University (SKKU), Suwon 16419, Korea.
authors.forename: Dong-Ki
authors.initials: DK
authors.lastname: Lee
mesh_terms: D052157:Aptamers, Nucleotide / Q000737:chemistry / Q000235:genetics*; D015374:Biosensing Techniques / Q000379:methods*; D004926:Escherichia coli / Q000235:genetics*; D012313:RNA / Q000737:chemistry / Q000235:genetics*; D052156:SELEX Aptamer Technique / Q000379:methods*
chemical_list: D052157:Aptamers, Nucleotide; D012313:RNA
keywords: Escherichia coli; aptamer; biolayer Interferometry; biosensor; cell-SELEX; impedimetric sensor