title: Label-free detection of endocrine disrupting chemicals by integrating a competitive binding assay with a piezoelectric ceramic resonator.
abstract: A piezoelectric biosensor for detection of endocrine disrupting chemicals (EDCs) was developed by incorporating chemical/biochemical recognition elements on the ceramic resonator surface for competitive binding assays. A facile electrodeposition was employed to modify the sensor surface with Au nanoparticles, which increased the surface area and enhanced the binding capacity of the immobilized probes. Thiol-labeled long chain hydrocarbon with bisphenol A (BPA) as head group was synthesized and self-assembled on the Au nanoparticle surface as the sensing probes, which showed a linear response upon the binding of estrogen receptor (ER-α) ranging from 1 to 30 nM. Detection of estrone, 17β-estradiol and BPA was achieved by integrating a competitive binding assay with the piezoelectric sensor. In this detection scheme, different concentrations of EDCs were incubated with 30 nM of ER-α, and the un-bounded ER-α in the solution was captured by the probes immobilized on the ceramic resonator, which resulted in the frequency changes for different EDCs. The biosensor assay exhibited a linear response to EDCs with a low detection limit of 2.4-2.9 nM (S/N=3), and required only a small volume of sample (1.5 µl) with the assay time of 2h. The performance of the biosensor assay was also evaluated for rapid and facile determination of EDCs of environmental relevant concentrations in drinking water and seawater, and the recovery rate was in the range between 94.7% and 109.8%.
authors.affiliation: Key Laboratory of Biochip Technology, Shenzhen Biotech and Health Centre, City University of Hong Kong, Shenzhen 518057, PR China; Department of Biology and Chemistry, and the State Key Laboratory of Marine Pollution, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong, PR China.
authors.forename: Liang-sheng
authors.initials: LS
authors.lastname: Hu
authors.forename: Chi-Chun
authors.initials: CC
authors.lastname: Fong
authors.forename: Lan
authors.initials: L
authors.lastname: Zou
authors.forename: Wing-Leung
authors.initials: WL
authors.lastname: Wong
authors.forename: Kwok-Yin
authors.initials: KY
authors.lastname: Wong
authors.forename: Rudolf S S
authors.initials: RS
authors.lastname: Wu
authors.forename: Mengsu
authors.initials: M
authors.lastname: Yang
mesh_terms: D001559:Benzhydryl Compounds / Q000302:isolation & purification*; D015374:Biosensing Techniques / Q000379:methods*; D002516:Ceramics / Q000737:chemistry; D052244:Endocrine Disruptors / Q000302:isolation & purification / Q000633:toxicity; D004784:Environmental Monitoring; D004958:Estradiol / Q000302:isolation & purification* / Q000633:toxicity; D047628:Estrogen Receptor alpha / Q000187:drug effects / Q000378:metabolism; D004970:Estrone / Q000302:isolation & purification* / Q000633:toxicity; D006046:Gold / Q000737:chemistry; D006801:Humans; D053768:Metal Nanoparticles / Q000737:chemistry; D010636:Phenols / Q000302:isolation & purification*; D012623:Seawater / Q000032:analysis; D014874:Water Pollutants, Chemical / Q000633:toxicity; D000098826:Bisphenol A Compounds
chemical_list: D001559:Benzhydryl Compounds; D052244:Endocrine Disruptors; D004958:Estradiol; D047628:Estrogen Receptor alpha; D004970:Estrone; D006046:Gold; D010636:Phenols; D014874:Water Pollutants, Chemical; C506487:ESR1 protein, human; C006780:bisphenol A; D000098826:Bisphenol A Compounds
keywords: Endocrine disrupting chemicals; Nanoparticle; Piezoelectric ceramic biosensor