Abstract: An assay chip includes a microchannel unit formed in a substrate. The microchannel unit includes a sample channel having inlet and outlet ends, a detection channel which intersects the sample channel and has an injection end and a recycle end on two opposite sides of the sample channel, respectively, and at least one light-exciting channel and at least one light-sensing channel disposed respectively adjacent to two opposite sides of the detection channel between the recycle end and the sample channel. A sensor unit includes first and second optical fibers inserted respectively into the light-exciting and light-sensing channels.

Abstract: The present invention relates to a chip-based device for three-dimensional microfluidic particle focusing and detection, characterized in which through the actions of fluidic driving force and dielectrophoretic forces, microparticles flow in the center of microchannels which enhances the accuracy of subsequent detection. The chip of the present invention is fabricated by first creating microchannels on a substrate for fluid flow, including specimen channels and sheath fluid channels, carrying out two-dimensional fluid focusing on particles in the sample flow, and fabricating microelectrodes in the microchannels to provide dielectrophoretic forces for three-dimensional focusing of particles. The present invention is applicable to the counting, determination, speed measuring and sorting of all kinds of microparticles, such as cells and blood cells.

Abstract: A method for modification of glass-based microchannels, which uses liquid organic-based solution containing siloxane for the modification of microchannels on the glass substrate, such as quartz, boron glass, sodium glass, and the like, to form a solid film to isolate the glass surface of the microchannels from the environment. Therefore, the present invention can be applied for electrophoresis experiment, so that the operation causes no electrical-double-layer effects, and further eliminates the occurrence of electro-osmosis flow, thus the separation efficiency of electrophoresis chips is improved.