Blood coagulant is an additive used in vacuum blood collection, and its function is as described in its name. It is mainly used for pre-treatment of blood samples before testing, quickly promoting blood coagulation, and facilitating sample testing. Efficient coagulation promoting powder, also known as high-efficiency silicifying agent, is a type of white powder mainly composed of polymer and coagulation factors. The university coagulation promoting powder produced by Desheng can be prepared into a water or alcohol suspension, sprayed on the inner wall of the test tube, dried at 40-50 ℃, or directly added to the test tube with a spoon. Generally, 0.5-1mg of this product can quickly coagulate 1ml of blood sample.