Microfluidic chip, and automatic separation and detection system and method for circulating tumor cell

A microfluidic chip, comprising;

• a density gradient centrifugation assembly,
• a cell capture assembly,
• and a reagent storage assembly,
• wherein the density gradient centrifugation assembly is configured to carry out density gradient centrifugation on a whole blood sample to achieve separation and obtain a plasma layer, a monocyte layer, a Ficoll solution layer, and an erythrocyte and granulocyte layer;
• the cell capture assembly comprises a capture channel, a capture inlet, and a capture outlet, the capture inlet and the capture outlet are in communication with the capture channel, an inner wall of the capture channel is provided with a plurality of capture holes and a plurality of negative-pressure capture chambers, each of the plurality of capture holes is in communication with one of the plurality of negative-pressure capture chambers correspondingly, the capture inlet is in communication with the density gradient centrifugation assembly for receiving the monocyte layer, the capture outlet is configured to be in communication with a negative-pressure source, and each of the plurality of negative-pressure capture chambers has a size that is larger than the size of one peripheral blood circulating tumor cell and smaller than the size of two peripheral blood circulating tumor cells;
• and
• the reagent storage assembly is in communication with the capture inlet, and is configured for storing a staining solution and a wash solution.