title: Chemiluminescent aptasensor capable of rapidly quantifying Escherichia Coli O157:H7.
abstract: Cost-effective and easy-to-use biosensor was developed for the rapid quantification and monitoring of Escherichia (E.) Coli O157:H7 in sample using E. Coli O157:H7 aptamer, graphene oxide (GO)/iron nanocomposites, and guanine chemiluminescence detection. E. Coli O157:H7 aptamer-conjugated 6-carboxyfluorescein (6-FAM) with excellent specificity captured E. Coli O157:H7 in a sample when the mixture was incubated for 1h at 37°C. Free E. Coli O157:H7 aptamers remaining in sample after the incubation were removed with GO/iron nanocomposites based on the principle of π-π stacking interaction between free aptamer and GO/iron nanocomposites. Then, E. Coli O157:H7 bound with aptamer-conjugated 6-FAM in sample emitted strong light when guanine chemiluminescent reagents (e.g., 3,4,5-trimethoxylphenylglyoxal hydrate, Tetra-n-propylammonium hydroxide) were added in the sample. The strength of light emitted in guanine chemiluminescence reaction was proportionally enhanced with the increase of E. Coli O157:H7 concentration. The limit of detection (LOD) of biosensor capable of quantifying E. Coli O157:H7 with good accuracy, precision, and reproducibility was as low as 4.5×10(3)cfu/ml. We expect that the rapid analytical system can be applied in the field of food safety as well as public health.
authors.affiliation: Luminescent MD, LLC, Hagerstown, MD 21742, United States.
authors.forename: Juna
authors.initials: J
authors.lastname: Khang
authors.affiliation: Luminescent MD, LLC, Hagerstown, MD 21742, United States.
authors.forename: Danial
authors.initials: D
authors.lastname: Kim
authors.affiliation: Luminescent MD, LLC, Hagerstown, MD 21742, United States.
authors.forename: Kang Wook
authors.initials: KW
authors.lastname: Chung
authors.affiliation: Luminescent MD, LLC, Hagerstown, MD 21742, United States. Electronic address: jhlee@luminescentmd.com.
authors.forename: Ji Hoon
authors.initials: JH
authors.lastname: Lee
mesh_terms: D064751:Ammonium Compounds / Q000737:chemistry; D052157:Aptamers, Nucleotide / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D015374:Biosensing Techniques / Q000379:methods*; D019453:Escherichia coli O157 / Q000302:isolation & purification* / Q000378:metabolism; D005456:Fluorescent Dyes / Q000737:chemistry; D006108:Graphite / Q000737:chemistry; D006147:Guanine / Q000737:chemistry; D057230:Limit of Detection; D008163:Luminescent Measurements; D010087:Oxides / Q000737:chemistry; D010658:Phenylglyoxal / Q000737:chemistry; D013997:Time Factors
chemical_list: D064751:Ammonium Compounds; D052157:Aptamers, Nucleotide; D005456:Fluorescent Dyes; D010087:Oxides; D006147:Guanine; D006108:Graphite; D010658:Phenylglyoxal
keywords: Aptamer; Aptasensor; E. Coli O157:H7; Food-borne pathogen; Guanine chemiluminescence; Nanocomposites