title: An aptamer-based dipstick assay for the rapid and simple detection of aflatoxin B1.
abstract: A rapid and simple dipstick assay based on an aptamer has been developed for the determination of aflatoxin B1 (AFB1). The dipstick assay format was based on a competitive reaction of the biotin-modified aptamer specific to AFB1 between target and cy5-modified DNA probes. Streptavidin and anti-cy5 antibody as capture reagents were immobilized at test and control lines on a membrane of the dipstick assay. After optimization, the limit of detection for the dipstick assay was 0.1 ng/ml AFB1 in buffer. The method was confirmed to be specific to AFB1, and the entire process of the assay can be completed within 30 min. Aqueous methanol (20%) provided a good extraction efficiency, and the matrix influence from corn extracts was successfully reduced through 2-fold dilution. The results of AFB1 analysis for corn samples spiked with known concentration of AFB1 by the dipstick assay and ELISA showed good agreement. The cut-off value of the dipstick assay for corn samples was 0.3 ng/g AFB1. Therefore, the dipstick assay is first reported and considered as a rapid, simple, on-site and inexpensive screening tool for AFB1 determination in grains as well as a corn.
authors.affiliation: Department of Chemistry, School of Physics and Chemistry, Gwangju Institute of Science and Technology (GIST), Gwangju 500-712, Republic of Korea.
authors.forename: Won-Bo
authors.initials: WB
authors.lastname: Shim
authors.affiliation: Department of Chemistry, School of Physics and Chemistry, Gwangju Institute of Science and Technology (GIST), Gwangju 500-712, Republic of Korea.
authors.forename: Min Jin
authors.initials: MJ
authors.lastname: Kim
authors.affiliation: Department of Chemistry, School of Physics and Chemistry, Gwangju Institute of Science and Technology (GIST), Gwangju 500-712, Republic of Korea.
authors.forename: Hyoyoung
authors.initials: H
authors.lastname: Mun
authors.affiliation: Department of Chemistry, School of Physics and Chemistry, Gwangju Institute of Science and Technology (GIST), Gwangju 500-712, Republic of Korea; Advanced Photonics Research Institute, Gwangju Institute of Science and Technology (GIST), Gwangju 500-712, Republic of Korea. Electronic address: mkim@gist.ac.kr.
authors.forename: Min-Gon
authors.initials: MG
authors.lastname: Kim
mesh_terms: D016604:Aflatoxin B1 / Q000032:analysis* / Q000235:genetics / Q000633:toxicity; D052157:Aptamers, Nucleotide / Q000235:genetics; D001483:Base Sequence; D015374:Biosensing Techniques / Q000379:methods* / Q000706:statistics & numerical data; D001710:Biotin; D002232:Carbocyanines; D015342:DNA Probes / Q000235:genetics; D005456:Fluorescent Dyes; D005506:Food Contamination / Q000032:analysis; D005516:Food Microbiology; D006801:Humans; D057230:Limit of Detection; D003313:Zea mays / Q000737:chemistry / Q000382:microbiology / Q000633:toxicity
chemical_list: D052157:Aptamers, Nucleotide; D002232:Carbocyanines; D015342:DNA Probes; D005456:Fluorescent Dyes; C085321:cyanine dye 5; D001710:Biotin; D016604:Aflatoxin B1
keywords: Aflatoxin B1; Aptamer; Corn; Dipstick assay; On-site detection