title: A highly sensitive differential pulse anodic stripping voltammetry for determination of 17β-estradiol (E2) using CdSe quantum dots based on indirect competitive immunoassay.
abstract: In this study a new and fast procedure was developed to determine trace 17β-estradiol (E2) concentrations using CdSe quantum dots (QDs) conjugation with bovine serum albumin (BSA)-E2. To increase the high efficiency of the method, the immunoassay design was restricted to an indirect competitive format. The E2 antigen and bioconjugate were incubated in a microtiter plate with an anti-E2 antibody and competition for antibody binding sites was established. The in situ bismuth-coated carbon electrodes were used for detecting the cadmium ions (Cd(2+)) released during the acid dissolution step. After optimization, the well-defined sharp anodic stripping voltammograms curves of the E2 concentration ranging from 50 to 1000 pg/mL was recorded, and the lowest detection limit was 50 pg/mL with 6% reproducibility and 7% repeatability. Finally, the assay was applied to tap water and wastewater samples. The detection limits were 52.56 ± 0.125 pg/mL for tap water and 51.42 ± 0.453 pg/mL for wastewater. These results show that the assay exhibited sensitive analytical performance in E2 detection with high sensitivity and accuracy with satisfactory results.
authors.affiliation: College of Environmental Science and Engineering, Donghua University, Shanghai 201620, PR China.
authors.forename: Nuanapa
authors.initials: N
authors.lastname: Chaisuwan
authors.forename: He
authors.initials: H
authors.lastname: Xu
authors.forename: Genying
authors.initials: G
authors.lastname: Wu
authors.forename: Jianshe
authors.initials: J
authors.lastname: Liu
mesh_terms: D000818:Animals; D001729:Bismuth / Q000737:chemistry; D019187:Cadmium Compounds / Q000737:chemistry*; D002417:Cattle; D055664:Electrochemical Techniques / Q000379:methods*; D004566:Electrodes; D004958:Estradiol / Q000032:analysis*; D007118:Immunoassay / Q000379:methods*; D057230:Limit of Detection; D045663:Quantum Dots; D018036:Selenium Compounds / Q000737:chemistry*; D012710:Serum Albumin, Bovine / Q000737:chemistry*; D062065:Wastewater / Q000032:analysis
chemical_list: D001729:Bismuth; D019187:Cadmium Compounds; D004958:Estradiol; D018036:Selenium Compounds; D012710:Serum Albumin, Bovine; D062065:Wastewater; C058667:cadmium selenide