title: An immunoassay for bisphenol A based on direct hapten conjugation to the polystyrene surface of microtiter plates.
abstract: Based on direct hapten coated format a competitive indirect enzyme-linked immunosorbent assay (ciELISA) for bisphenol A (BPA) was developed. Polystyrene surface was modified by 3-Aminopropyltriethoxysilane (APTES) to produce amino groups after H(2)SO(4)/HNO(3)-pre-treatment. 4,4-bis (4-hydroxyphenyl) valeric acid (BVA) which is analogue of BPA, was successfully immobilized on the surface of microtiter plates by N,N'-dicyclohexylcarbodiimide (DCC) method. The essential steps of the assay were optimized, especially blocking procedure which is key step to prevent unspecific binding of antibody. The results indicated that compared with hapten-protein coated format (IC(50)=176.67 ng ml(-1), LOD=15.90 ng ml(-1)), the direct hapten coated format (IC(50)=23.50 ng ml(-1), LOD=0.27 ng ml(-1)) could improve assay sensitivity and the detection ranges were 2.30 ng approximately 157.60 ng ml(-1) with good signal reproducibility (P value>0.05) after careful optimization of assay conditions. Tap water samples and seawater samples were spiked with a known amount of BPA and measured by ciELISA. The average recoveries were between 70 and 142%. As far as we are aware this is the most sensitive ELISA for BPA yet reported.
authors.affiliation: College of Food Science and Technology, Huazhong Agricultural University, Wuhan, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Feng
authors.forename: Baoan
authors.initials: B
authors.lastname: Ning
authors.forename: Pu
authors.initials: P
authors.lastname: Su
authors.forename: Hongyong
authors.initials: H
authors.lastname: Wang
authors.forename: Caihong
authors.initials: C
authors.lastname: Wang
authors.forename: Fusheng
authors.initials: F
authors.lastname: Chen
authors.forename: Zhixian
authors.initials: Z
authors.lastname: Gao
mesh_terms: D000818:Animals; D001559:Benzhydryl Compounds; D002417:Cattle; D004024:Dicyclohexylcarbodiimide / Q000737:chemistry; D006241:Haptens / Q000737:chemistry*; D007118:Immunoassay / Q000295:instrumentation / Q000379:methods*; D013058:Mass Spectrometry; D015394:Molecular Structure; D017942:Nitric Acid / Q000737:chemistry; D010636:Phenols / Q000032:analysis* / Q000737:chemistry; D011137:Polystyrenes / Q000737:chemistry*; D011437:Propylamines; D015203:Reproducibility of Results; D012710:Serum Albumin, Bovine / Q000737:chemistry; D012821:Silanes / Q000737:chemistry; D013056:Spectrophotometry, Ultraviolet; D013464:Sulfuric Acids / Q000737:chemistry; D013499:Surface Properties; D000098826:Bisphenol A Compounds
chemical_list: D001559:Benzhydryl Compounds; D004024:Dicyclohexylcarbodiimide; D006241:Haptens; D017942:Nitric Acid; D010636:Phenols; D011137:Polystyrenes; D011437:Propylamines; D012710:Serum Albumin, Bovine; D012821:Silanes; D013464:Sulfuric Acids; C477625:amino-propyl-triethoxysilane; C006780:bisphenol A; D000098826:Bisphenol A Compounds; C033158:sulfuric acid