Prostate-specific antigen immunoassays on the BioCD.
The BioCD is a spinning-disc interferometric biosensor on which antibodies are immobilized to capture target antigens from biological samples. In this work, BioCDs measured the interferometric response to prostate-specific antigen (PSA). The ideal detection limit for PSA was determined using a BioCD with 12,500 printed target antibody spots with a corresponding number of reference protein spots. Statistical analysis projects the detection limit of PSA as a function of the number of spots included in the average. When approximately 10,000 spot pairs were averaged, the 3sigma detection limit was 60 pg/ml in a 2 mg/ml simple protein background. A standard format for BioCD immunoassays uses 96 wells with 32 target spots paired with reference spots. In serum, the detection limit for this format was 1 ng/ml in 3:1 diluted female human serum using a sandwich assay with a nonfluorescent mass tag.
Wang
Xuefeng
X
Department of Physics, Purdue University, 525 Northwestern Avenue, West Lafayette, IN 47907-2036, USA. wang137@purdue.edu
Zhao
Ming
M
Nolte
David D
DD
D015374:Biosensing Techniques; D005260:Female; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D017430:Prostate-Specific Antigen / Q000032:analysis*; D012680:Sensitivity and Specificity
D017430:Prostate-Specific Antigen