Development of Portable Device for Point-of-Care Testing of Tumor Marker

By combining electrochemical detection technique and electronic technique, a portable device which adopted differential pulse voltammetry (DPV) measurement was developed to meet the needs of high sensitivity and on-site rapid detection of tumor marker. The voltage and current resolution of portable device were 0.8 mV and 1 nA, respectively. Combined with home-made microfluidic paper-based analytical device, carcinoembryonic antigen (CEA) was detected by portable device. Experimental results revealed that the DPV peak currents showed good linear relationship with the logarithm of CEA concentration in the range of 1–500 μg L⁻¹. The corresponding correlation coefficient was 0.998 and the limit of detection was 10 ng L⁻¹. According to the principle of specific binding of antibody and antigen with electrochemical detection, CEA concentration could be calculated automatically according to the linear equation. The portable device with the features of high sensitivity and low detection limit could be widely used in the point-of-care testing of tumor marker.