Sensitive detection of tumor marker CA15‐3 in human serum by capillary electrophoretic immunoassay with chemiluminescence detection

Abstract

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.

Microchip fluorescence-enhanced immunoaasay for simultaneous quantification of multiple tumor markers

“…While in the sera of cancer patients, CA125 and CA15-3 had the serum levels ranged from 92.5 to 368.3 U/mL and 63.3 to 198.4 U/mL, respectively. These results demonstrated that the serum CA125 and CA15-3 levels were higher remarkably in cancer patients compared to normal persons, which was in agreement with previous reports [34,35].…”

Gold nanoparticle-based low limit of detection Love wave biosensor for carcinoembryonic antigens

“…However, these trace protein biomarkers, such as CEA, CA125 and Bcl-2, are present in a very low concentration level in serum or urine of cancer patients (Anderson et al 2009;Drenberg et al 2010;Ni et al 2005). Traditional assay methods such as enzyme-linked immunosorbent assay (ELISA) (Butler 2000), radioimmunoassay (Kato and Torigoe 1977), fluorescence immunoassay (Hicks 1984), electrophoretic immunoassay (Liu et al 2008) and mass spectrometric immunoassay (Nelson et al 1995) have some disadvantages, such as requiring labeled markers, long processing times and requiring expensive instruments. Thus, the demand for rapid, operationally simple, ultrasensitive biosensors is increasing, especially those capable of point of care use.…”

Capillary electrophoresis–based immunoassay and aptamer assay: A review

“…Nevertheless, the connection of the term “noncompetitive immunoassay” with CE was used a little later in 1993 by Schultz and Kennedy . Several articles were published about using this format for studying proteins , peptides , hormones , and also tumor markers . Other practical applications with details are summarized in Table .…”