Biological microchip for a simultaneous quantitative immunoassay of tumor markers in human serum.

The biochip was constructed for simultaneous assay of total and free prostate-specific antigen, alpha-fetoprotein, cancer embryonic antigen, human chorionic gonadotropin, and neuron-specific enolase. These biochips represent an array of gel elements with covalently immobilized proteins. The major analytic characteristics of the developed method were obtained. It was shown that the results of simultaneous assay of six tumor markers in blood serum well correlated with routine measurement of each marker using enzyme immunoassay kits. This approach allowed us to reveal the hook effect of high concentrations during biochip assay, which prevents distortion of the diagnostic picture at high concentration of the analyte in the sample.