The Key Points When Using the Microporous Membrane Filter
(1) The determination of foaming point: The measurement of foaming point pressure can reflect the pore size of microporous membrane, which is closely related to the quality of filtered liquid, and is an important means to ensure the quality of microporous membrane. The microporous membrane should be placed in the water of 70 h for 1 h. Pour water out and then soak in warm water for overnight use. When used, remove it and rinse it with water for injection, then you can install it in the filter. Prevent the filter from being tilted and leaked.
(2) In order to prolong the service life of the filter membrane, the filter paper or silk cloth of the same size can be used (the silk cloth should be boiled for about 30 minutes with 20 g.L-1 sodium sulfonate solution, and then cleaned with water for injection) on the filter membrane to prevent the membrane from breaking.
(3) The pore diameter of the microporous membrane is cone-shaped, and the smooth one is small to the front; the rough one is large to the reverse, so it should be installed with the front facing down, the reverse facing up, otherwise it is easy to be blocked by impurities, affecting the filtration rate. When the temperature is low, the treated membrane should be immersed in water for injection at the same temperature as the liquid medicine for 5-10 minutes, which can avoid the phenomenon that the tensile strength of the membrane decreases due to the temperature difference.
(4) Fixed a No. 16 transfusion needle on the skin tube head of the exhaust pipe of the filter rack and controlled by a water stop clip, the filter membrane can be prevented from breaking when the exhaust pressure and velocity are too high.
(5) Do not sterilize the filter holder together with the filter membrane. Otherwise, the filter membrane will be brittle and cracked due to thermal expansion and shrinkage.
(6) After use, the microporous membrane is placed in the water for injection to prevent drying, but do not soak it for too long. The microporous membrane which has been dehydrated and dried cannot be used
(7) According to the concentration and viscosity of the solution, microporous membrane with different apertures should be selected.
(8) If it is found that there are small holes or small cracks in the microporous membrane, it can be rinsed and dried with the original unused membrane, then torn and placed in a small cup of acetone, stirred into a paste mucus, the mucus droplets in the flat membrane hole or small cracks, not too much mucus can be covered and slightly larger, can be continued after drying. Use without affecting.
(9) Microporous membrane can be used as final filtration when multistage filtration device is used for transfusion filtration. Pressurized, decompressed and azimuthal static pressure filtration should be adopted.