A novel multi-array immunoassay device for tumor markers based on insert-plug model of piezoelectric immunosensor

A novel multi-array immunoassay device based on the insert-plug model of piezoelectric (Pz) immunosensor fabricated with the screw clamp apparatus has been developed for quantitative detection of tumor markers such as alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA), prostate specific antigen (PSA), and carcinoma antigen 125 (CA125) in serum, in which single immunosensor can oscillate independently with the frequency stability of ±1 Hz (hertz) in air phase and ±2 Hz in liquid phase. These response characteristics of Pz tumor marker multi-array immunoassay device such as time-cost, reproducibility and specificity, etc. were also investigated, respectively. The detection range for AFP, CEA, PSA and CA125 obtained by multi-array Pz immunosensor were 20–640 ng/ml, 1.5–30 μg/ml, 1.5–40 ng/ml and 5–150 IU/ml, respectively, with the coefficient of variance (CV) less than 5% and no cross-reactivates with other tumor markers in serum were observed. Application of the multi-array immunosensor to clinical samples demonstrated that results were in good agreement with chemiluminescence immunoassay (CLIA). Moreover, the multi-array Pz immunosensor could be regenerated to be reused for three cycles without appreciable loss of response activity. Therefore, the proposed multi-array immunoassay device based on Pz immunosensor provides a rapid, sensitive, specific, reusable, convenient and reliable alternative for the detection of tumor markers in clinical laboratory.