Centrifugal Microfluidic Platform For Detection Of Carcinoembryonic Antigen In Serum

Carcinoembryonic antigen(CEA) is a kind of glycoprotein, which is widely exists in the serum of digestive system cancer, mammary cancer and lung cancer. It is a broad spectrum tumor marker. It is currently recognized as one of the six tumor markers with definite diagnostic value. Real time monitoring with concentration of CEA in serum can better detect the development of the disease and judge the curative effect of medicine.The traditional detection method of CEA is immune, which need repeated washing-separation operation. It is tedious and time consuming. In this paper, first using chitosan as medium density under the centrifugal sedimentation principle. And developing a method of detecting CEA. On the 14 pencil type channel disc chip which are pre-storaging medium density, detecting fluorescence after one-step centrifugal the bead complex and solution will be separated completely. This method achieve a high throughput, rapid.convenient detection of CEA.In the experiment, we verified the feasibility about using micro-beads instead of the conventional orifice plate as solid substrate. The separation effect of percoll, dextran and chitosan three medium density were investigated, found that 2% chitosan solution separation effect was significantly higher than others. Then, the chip channel with different inclined angles is selected, and the channel with 0 degree inclination angle is finally selected. The centrifugal speed and time, in this paper were optimized. Eventually in 2500r/min speed conditions for 2.5min centrifugal, the bead complex and the solution are completely separated. The standard curve of the relationship between the concentration of the antigen and the fluorescence intensity was obtained by using the developed method, and the linearity in 0.7-22.5 ng/mL concentration range is good (R2=0.993). Finally 32 patients with known concentrations of CEA serum samples were detected and compared with the actual concentration, found there are no significant difference between the testing results using this method and the hospital provided, so experimental method established in this paper has potential application value in clinical biomarker detection measured.