When Xia Mier cut 200bp is used to press the nose, the mass and concentration of the separated substance should be determined first, and the correct concentration of the separated substance can better complete the accurate separation. In addition, consideration should be given to selecting appropriate membrane materials to achieve the best separation performance. Generally, hollow glass film or nano-composite film is used to realize the head pressure of Xia Mier cut 200bp. Next, adjust the head pressure, which should be adjusted to the analog value to keep the pressure between 200-400 psi. In addition, the head pressure should also be adjusted according to the different sample size and particle size to ensure the best separation performance.