title: Development of a bi-enzyme tracer competitive enzyme-linked immunosorbent assay for detection of thiacloprid and imidaclothiz in agricultural samples.
abstract: A bi-enzyme tracer direct competitive enzyme-linked immunosorbent assay (dc-ELISA) was developed based on anti-imidaclothiz and anti-thiacloprid antibodies. Several affected physicochemical factors were optimised, including methanol concentration, ionic strength and pH value. Under the optimised conditions, 50% inhibiting concentration (IC50) values for thiacloprid and imidaclothiz were 182.62 and 58.17 μg/L, with a limit of detection (LOD) of 4.25 and 2.12 μg/L, respectively. There was no obvious cross reactivity (CR) between the two pesticides with most neonicotinoids pesticides except imidacloprid. The method analyzing the spiked samples of tomato, pear and cabbage showed satisfying recoveries (85.27-113.07%). Comparable dissipation of thiacloprid and imidaclothiz in authentic tomato samples determined with the dc-ELISA and high performance liquid chromatography (HPLC) indicated that dc-ELISA is suitable for monitoring thiacloprid and imidaclothiz residues simultaneously in agricultural samples.
authors.affiliation: School of Pharmacy, Jilin University, Changchun 130021, China.
authors.forename: Hongxia
authors.initials: H
authors.lastname: Li
authors.affiliation: Department of Analytical Chemistry, College of Chemistry, Jilin University, Changchun 130012, China.
authors.forename: Xu
authors.initials: X
authors.lastname: Yan
authors.affiliation: Department of Pesticide Science, College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Haiyan
authors.initials: H
authors.lastname: Shi
authors.affiliation: School of Pharmacy, Jilin University, Changchun 130021, China. Electronic address: xiaohongyang88@126.com.
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Yang
mesh_terms: D001937:Brassica / Q000737:chemistry*; D018556:Crops, Agricultural / Q000737:chemistry; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D005506:Food Contamination / Q000032:analysis; D005638:Fruit / Q000737:chemistry; D007306:Insecticides / Q000032:analysis*; D057230:Limit of Detection; D018551:Solanum lycopersicum / Q000737:chemistry*; D000073943:Neonicotinoids; D010573:Pesticide Residues / Q000032:analysis*; D011725:Pyridines / Q000032:analysis*; D031989:Pyrus / Q000737:chemistry*; D013843:Thiazines / Q000032:analysis*; D013844:Thiazoles / Q000032:analysis*
chemical_list: D007306:Insecticides; D000073943:Neonicotinoids; D010573:Pesticide Residues; D011725:Pyridines; D013843:Thiazines; D013844:Thiazoles; C417209:thiacloprid; C550087:imidaclothiz
keywords: Agricultural samples; Bi-enzyme tracer ELISA; High performance liquid chromatography; Neonicotinoid insecticides