Detection of 17β-estradiol in river and human urine by highly sensitive chemiluminescent enzyme immunoassay

A highly sensitive chemilumineseent enzyme immunoassay (CLEIA) for the determination of the 17 beta-estradiol (E-2) in river and human urine was developed by using the FITC-anti-FITC system as solid phase, the avidin-blotin system as signal amplification system, and the highly sensitive 4-methoxy-4-(3-phosphatephenyl)-spiro-(1,2-dioxetane-3,2'-adamantane) AMPPD)-alkaline phosphatase (ALP) system as chemilumineseence detection. After optimizing the conditions of enzyme reaction, the linear range of E, was in the range of 2.5 - 2000 ng/L, detection limit was 1.1 ng/L. The RSDs of intra- and inter-assay were both below 10%. The percent recoveries are in the range of 92% - 112% in human urine. This method has been successfully applied to detect E-2 in river water and human urine. The concentration of E-2 in river water was in the range of 0.15 - 0.57 ng/L, and in human urine was in the range of 0.75 - 135 mu L.