The invention discloses a micro-fluidic
chip. The micro-fluidic
chip comprises positioning holes located in four corners of a
chip body, a sample adding hole, a sample reaction cavity, a physical screening flow channel, a
liquid waste flow channel, a
liquid waste collecting cavity, a magnetic adsorption cavity plated with a
magnet on the upper surface, a product flow channel, a product collectingcavity and a product absorption hole, wherein the sample reaction cavity and the magnetic adsorption cavity are communicated through the physical screening flow channel; the magnetic adsorption cavityand the product collecting cavity are communicated through the product flow channel; the lower side wall of the physical screening flow channel is communicated with the
liquid waste flow channel through a notch formed in the lower side wall. The invention further discloses a method for enriching and purifying CTCs (circulating
tumor cells) by adopting the micro-fluidic chip. An experiment can becompleted by only one centrifugal
machine, the operation is fast and simple, an expensive EpCAM
antibody is not needed, and the cost is relatively low; the obtained CTCs not only expresses the type ofthe EpCAM
antibody, but also has better separation and purification effects, no immunomagnetic beads exist on the surface, and
biological activity of the micro-fluidic chip is better.