The Establishment Of A Simple And Sensitive Aptamer-based Method For Organophosphorus Pesticide

Pesticide residue is one of the key issues affecting food quality and safety in China. It does not only seriously hinder the economic development of Chi na’s foreign trade, but also threatened human healthy. The organophosphorus pesticides are the largest amount of the use of pesticides and re sidues. Current ly, many detection methods of pesticide residues have been employed, including different physicochemical analysis methods, such as high performance liquid chr omatography( HPLC), capillary electrophoresis(CE), gas chromatography(GC), and biological detection methods, such as enzyme biose nsor and immuno-biosensor. Howeve r, up to date,all of those methods require either complicate pr otocol s or expensive equipment.Envisaging this situation, this study aimed to establish a s imple, r apid, high spe cificity method for detection of organophosphorous.Aptamers are arti fici al nucle ic aci d fragme nts, such as ribonucleic acid(RNA)and si ngle-strand deoxyribonucle ic acid(ssDNA) molecules, which can respectively bind to many targets, such as, a mino acid, protein, inorganic ion or drug. They have many advantages, such as high affinity and specificity, easy synthesis, low cost, and thermal stability. Aptamers have been appl ied in many aspects, suc h as, used as drug,as a t ool for de live r y of drug, as a reagent for det ection of sma ll organic s, biomarker and pathogen. Aptamer also can be used for bioimagi ng.The present study aime d to establ ish an aptamer-base d simple and high spe cificity detection method focusing on organophosphorus pe sticide profenofos r esidue a s a breakthrough point. According to t he characteristics of aptamer and the Gold nanoparticles, an optical aptamer sensor for detection of pesticide has been generated. Its sensiti vity, specificity and stability have been analyzed. We have demonstrated that the new method could be used to det ect profenofos pesti cide at6 nM level with strong spec ificity and good stability. The method exhibited its advantages, simple, ra pid and high specifi city. And i n t he detection of the actual pes tic ide re sidues, the detect ion le vel re ached 10-7M.Our data provides e xperimenta l basis for the application of aptamers in detection of pest ici de residues, also provi des a theoretical ba sis for the deve lopment of rapid detection technology.