title: Selection of DNA aptamers that bind to four organophosphorus pesticides.
abstract: Single-stranded DNA (ssDNA) aptamers against four organophosphorus pesticides (phorate, profenofos, isocarbophos and omethoate) were simultaneously isolated from an immobilized random ssDNA library by systematic evolution of ligands by exponential enrichment (SELEX) technique. After 12 rounds of in vitro selection, five ssDNA aptamer candidates were selected and their binding affinities were identified by a novel method using a molecular beacon. Two of the five ssDNA sequences, SS2-55 and SS4-54, demonstrated higher affinities and specificities to the four organophosphorus pesticides. They were defined as broad-spectrum aptamers binding to four different targets and their simulated secondary structures showed highly distinct features with typical stem and loop structures. The dissociation constant of SS2-55 and SS4-54 binding to the four organophosphorus pesticides ranged from 0.8 to 2.5 μM. These aptamers offered application potential in the analysis and/or neutralization of the residues of the four organophosphorus pesticides.
authors.affiliation: College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China. wangli7742@126.com
authors.forename: Li
authors.initials: L
authors.lastname: Wang
authors.forename: Xianjin
authors.initials: X
authors.lastname: Liu
authors.forename: Qiang
authors.initials: Q
authors.lastname: Zhang
authors.forename: Cunzheng
authors.initials: C
authors.lastname: Zhang
authors.forename: Yuan
authors.initials: Y
authors.lastname: Liu
authors.forename: Kang
authors.initials: K
authors.lastname: Tu
authors.forename: Jian
authors.initials: J
authors.lastname: Tu
mesh_terms: D052157:Aptamers, Nucleotide / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D004277:DNA, Single-Stranded / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D015723:Gene Library; D008958:Models, Molecular; D009690:Nucleic Acid Conformation; D009943:Organophosphorus Compounds / Q000378:metabolism*; D010575:Pesticides / Q000378:metabolism*; D052156:SELEX Aptamer Technique; D013379:Substrate Specificity
chemical_list: D052157:Aptamers, Nucleotide; D004277:DNA, Single-Stranded; D009943:Organophosphorus Compounds; D010575:Pesticides