Design, fabrication and detection of an integration micorfluidic chip

In this work, an integrated microfluidic chip with a multi-layer structure was designed, fabricated and detected for blood plasma isolation, mixing and immunoassays. Plasma was continuously separated from whole blood based on crossflow filtration principle by using a filter membrane. Then the isolated plasma and reagents were mixed in a crooked microchannel with shrunk structures and expanded structures in turns. Finally, immunoassays were implemented by the fluorescence detection technology. Under the optimal condition, the detected range of human IgG is 0.5∼5 μg/mL with a correlation coefficient of 0.9788. The integrated microfluidic chip has several advantages of lower cost, lower reagent and sample consumption, less analytical time and also disposability, which enables on-site detection for point-of-care clinical testing.