title: Fluorescence assay based on aptamer-quantum dot binding to Bacillus thuringiensis spores.
abstract: A novel assay was developed for the detection of Bacillus thuringiensis (BT) spores. The assay is based on the fluorescence observed after binding an aptamer-quantum dot conjugate to BT spores. The in vitro selection and amplification technique called SELEX (Systematic Evolution of Ligands by EXponential enrichment) was used in order to identify the DNA aptamer sequence specific for BT. The 60 base aptamer was then coupled to fluorescent zinc sulfide-capped, cadmium selenide quantum dots (QD). The assay is semi-quantitative, specific and can detect BT at concentrations of about 1,000 colony forming units/ml.
authors.affiliation: Department of Chemistry and Biochemistry, Texas State University-San Marcos, 601 University Drive, San Marcos, TX 78666, USA.
authors.forename: Milada
authors.initials: M
authors.lastname: Ikanovic
authors.forename: Walter E
authors.initials: WE
authors.lastname: Rudzinski
authors.forename: John G
authors.initials: JG
authors.lastname: Bruno
authors.forename: Amity
authors.initials: A
authors.lastname: Allman
authors.forename: Maria P
authors.initials: MP
authors.lastname: Carrillo
authors.forename: Sulatha
authors.initials: S
authors.lastname: Dwarakanath
authors.forename: Suneetha
authors.initials: S
authors.lastname: Bhahdigadi
authors.forename: Poornima
authors.initials: P
authors.lastname: Rao
authors.forename: Johnathan L
authors.initials: JL
authors.lastname: Kiel
authors.forename: Carrie J
authors.initials: CJ
authors.lastname: Andrews
mesh_terms: D052157:Aptamers, Nucleotide / Q000138:chemical synthesis / Q000737:chemistry*; D001413:Bacillus thuringiensis / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification*; D019187:Cadmium Compounds / Q000737:chemistry; D015169:Colony Count, Microbial / Q000379:methods*; D005453:Fluorescence; D045663:Quantum Dots; D018036:Selenium Compounds / Q000737:chemistry; D013050:Spectrometry, Fluorescence / Q000379:methods*; D013171:Spores, Bacterial / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification; D013440:Sulfides / Q000737:chemistry; D017967:Zinc Compounds / Q000737:chemistry
chemical_list: D052157:Aptamers, Nucleotide; D019187:Cadmium Compounds; D018036:Selenium Compounds; D013440:Sulfides; D017967:Zinc Compounds; C058667:cadmium selenide; C031238:zinc sulfide