Direct immunoassay of estriol in pregnancy serum by capillary electrophoresis with laser-induced fluorescence detector.
A simple and sensitive capillary electrophoretic immunoassay (CEIA) was described for the determination of estriol (E(3)) in pregnant women's serum. The method was based on the competitive reaction of fluorescein-labeled E(3) antigen and E(3) with limited amounts of monoclonal antibody. The addition of the thermally reversible hydrogel, poly-N-iso propylacrylamide (pNIPA) in the buffer serving as a replaceable packing material, improved the reproducibility of the method. With laser-induced fluorescence detector (LIF), this method can be applied to determine E(3) at concentrations lower to 31.6 pg ml(-1). Recoveries from human steroid-free serum matrix were greater than 94% with relative standard deviation (R.S.D.) values less than 3.5%. Serum E(3) levels of ten normal pregnant women were measured at the range of 10.2-15.6 ng ml(-1).
Su
Ping
P
College of Chemistry and Molecular Engineering, Peking University, Beijing, China. suping@chem.pku.edu.cn
Zhang
Xin-Xiang
XX
Wang
Yong-Cheng
YC
Chang
Wen-Bao
WB