Sensitive detection of tumor marker CA15-3 in human serum by capillary electrophoretic immunoassay with chemiluminescence detection.
A new and sensitive non-competitive immunoassay (IA) for tumor marker carbohydrate antigen 15-3 (CA15-3) by CE coupling with ECL detection has been developed. This method is based on luminol-H(2)O(2 )reaction catalyzed by horseradish peroxidase (HRP). The optimum CE separation and CL detection conditions were investigated. After the non-competitive immunoreaction, the free HRP-labeled CA15-3 antibody (Ab*) and the bound Ab*-antigen (Ab*-Ag) complex were separated in a separation capillary and then catalyzed the CL reaction of luminol and H(2)O(2 )in a reaction capillary following the separation capillary. The calibration curve based on the peak areas of Ab*-Ag complex plotted against the concentrations of CA15-3 is in the range of 0-250 U/mL with a correlation coefficient of 0.9983 and the detection limit is 0.035 U/mL (S/N = 3). The response for five consecutive injections of 125 U/mL CA15-3 resulted in RSDs of 0.83% and 3.1% for the migration time and the peak area, respectively. The method was successfully used for the quantification of CA15-3 in human sera obtained from healthy persons and from patients with breast cancer.
Liu
Yan-Ming
YM
College of Chemistry and Chemical Engineering, Xinyang Normal University, Xinyang, China. liuym9518@sina.com
Zheng
Yan-Li
YL
Cao
Jun-Tao
JT
Chen
Yong-Hong
YH
Li
Fu-Rong
FR
D014408:Biomarkers, Tumor / Q000097:blood*; D002021:Buffers; D006735:Horseradish Peroxidase / Q000378:metabolism; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007118:Immunoassay / Q000379:methods*; D008163:Luminescent Measurements / Q000379:methods*; D012680:Sensitivity and Specificity
D014408:Biomarkers, Tumor; D002021:Buffers; D006735:Horseradish Peroxidase