title: Novel automated flow-based immunosensor for real-time measurement of the breast cancer biomarker CA15-3 in serum.
abstract: A novel automated immunosensor assay has been developed for real-time measurement of the breast cancer biomarker CA15-3 in serum. The assay employed the kinetic-exclusion analytical technology of the KinExA™ 3200 instrument. Polymethylmethacrylate (PMMA) beads coated with CA15-3 were used as capturing reagent, mouse anti-CA15-3 monoclonal antibody was used as primary antibody, and the fluorescence was monitored and recorded during the flow of the fluorescent-labeled antibody through the beads. The fluorescence signal retained on the beads was plotted versus CA15-3 concentration to generate a calibration curve. The concentrations of CA15-3 in the samples were then obtained by interpolation on the curve. The assay limit of detection was 0.2 IU mL(-1). This highly sensitive automated system allowed rapid and reliable quantification of CA15-3 without any matrix effect; analytical recovery of serum-spiked CA15-3 was 90.7%-108.6%±2.05%-7.45%. The precision of the sensor was satisfactory; relative standard deviation (RSD) was 3.8%-5.1% and 5.2%-7.4% for the intra- and inter-assay precision, respectively. The analytical performance of the proposed sensor was superior to the non-competitive sandwich immunoassays for CA15-3. The automated analysis by the sensor facilitated the processing of a large number of specimens, and the new sensor-based assay is anticipated to have a great value in measurement of CA15-3.
authors: Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, P.O. Box 2457, Riyadh 11451, Saudi Arabia. idarwish@ksu.edu.sa
authors: Ibrahim A
authors: IA
authors: Darwish
authors: Tanveer A
authors: TA
authors: Wani
authors: Nasr Y
authors: NY
authors: Khalil
authors: Diane A
authors: DA
authors: Blake
mesh_terms: D000818:Animals; D015295:Antigens, Tumor-Associated, Carbohydrate / Q000097:blood*; D001331:Automation; D014408:Biomarkers, Tumor / Q000097:blood*; D015374:Biosensing Techniques / Q000379:methods*; D001943:Breast Neoplasms / Q000097:blood*; D002138:Calibration; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D006801:Humans; D057230:Limit of Detection; D013997:Time Factors
chemical_list: D015295:Antigens, Tumor-Associated, Carbohydrate; D014408:Biomarkers, Tumor