Direct immunoassay of estrone by capillary electrophoresis with laser‐induced fluorescence detection

Abstract

An immunoassay for estrone (E(1)) in women's serum, based on the competitive reaction between fluorescein-labeled complete antigen and E(1) with limited amount of anti-estrone monoclonal antibody is described. A thermally reversible hydrogel, poly-N-isopropylacrylamide (pNIPA), was added to the buffer to improve the reproducibility. With a laser-induced fluorescence (LIF) detector, the capillary electrophoretic immunoassay (CEIA) can be applied to determine E(1) at a concentration lower than 19.6 pg/mL. The E(1) levels in ten normal women's serum were measured at the range of 118.6-222.0 pg/mL.

A sensitive immunoassay for determination of hepatitis B surface antigen and antibody in human serum using capillary electrophoresis with chemiluminescence detection

“…Therefore, no reports were found using HPLC methods for determination of HBV. Laser induced fluorescence (LIF) detection is still the usual choice in CEIA because of its high sensitivity, commercially available apparatus and the ease in the preparation of fluorescent-labeled tracer [19][20][21][22][23][24][25][26][27]. Apart from LIF detection, CL detection has received much attention due to its high sensitivity, low cost, wide linear range and having no use for excitation sources, while few reports have been found using CEIA with CL detection [28,29] including the successful application of it to quantification of CA125 in human sera and determination of bone morphogenic protein-2 in rat vascular smooth muscle cells.…”

Immunoaffinity CE in clinical analysis of body fluids and tissues

“…The addition of a thermally reversible hydrogel (pNIPA) was shown to improve reproducibility and separation power of the method. Similar competitive immunoassays of estrone (E 1 ) in the serum of young women (LOD,19.6 pg/mL) [64] and estradiol in simulated serum samples (LOD 10 211 M) after removal of other hormones [65] have been reported.…”

“…With LIF detection, the LOD values for Dz were 16.5 pM in aqueous matrix and 62.5 pM in both urine and plasma. Zhang and co-workers [51,64,65] have reported clinical APCE analysis of estrogens. A competitive immunoassay of estriol (E 3 ) in pregnancy serum was based on the competition between serum-derived E 3 and FITC-labeled E 3 -conjugate for binding of a limited amount of anti-E 3 -antibody [51].…”

Antibody development to testosterone and its application in capillary electrophoresis‐based immunoassay

“…The analyte can therefore be determined based on comparing the concentration of Ag * (or Ab * ) and Ag * -Ab (or Ab * -Ag) complex. Since Nielsen first introduced CEIA in 1991 using a UV detector [21], CEIA techniques have been widely applied for the detection of proteins [22][23][24], peptides [25][26][27], hormones [28][29][30], and abused drugs [31][32][33][34] with the aid of a highly sensitive LIF detector. As labeled macromolecules (Ag or Ab) are generally used in CEIA, there are still some challenges in developing CEIA.…”