Filter membrane is essential to use with syringe filter in the syringe to filter chemically turbid solution samples, most commonly used in chemical HPLC-MS/GC-MS analysis of liquid and gas dust removal, sterilization filtration, biological sample preparation, filtering of tissue culture medium, microbial media, buffer solutions, etc.
There are different filter membranes adopted in the syringe filter to meet different requirements. Today, HAWACH will mainly discuss the mixed cellulose ester(MCE) filter membrane in the syringe filter.
The mixed cellulose ester filter membrane is made of refined nitrocellulose, added with an appropriate amount of cellulose acetate, acetone, n-butanol, ethanol, etc. It is hydrophilic, non-toxic, and hygienic. It is a porous membrane filter material with a comparative pore size distribution and its uniform penetrating micropores with a microporosity of up to 80‰. The MCE filter membrane is mainly used for the filtration of water-based solutions, so it is also called a water-based membrane. The mixed cellulose ester(MCE) filter membrane is flammable. When storing, it should be sealed, moisture-proof, and fire-proof.
The main application of mixed cellulose ester filter membrane
1. The pharmaceutical industry requires autoclaving, water injection, large infusion, traditional Chinese medicine extraction, and beverage filtration to remove particles, which can improve the internal quality of drugs and the pass rate of clarity and sterilization of heat sensitive drugs (insulin ATP, coenzyme A, and other biochemical preparations).
Use 0.45 micron filter membrane (or 0.3 microns, 0.2 micron filter membrane), the sterility test of antibiotic film method.
2. Medical and sanitation, the detection of human body fluids and bloodworms, and the detection of coli-group in drinking water, surface water, and well water.
3. Analysis and determination of particles and oil insoluble matter in solution, and determination of water pollution index.
4. Applied to research departments such as somatic cell hybridization and mitochondrial complementation to predict heterosis.
5. Fine filtration of high-purity water in the electronics industry.
6. The filter membrane must be in a wet state when filtering liquid. If the filter membrane becomes dry due to disinfection, it must be wetted with sterile water. If the wetting is not good, the flow rate must be disinfected before the sterilization filtration. And then carry out sterilization filtration in a sterile room, which should be carried out strictly in accordance with the sterilization operating procedures, with a nominal pore size of 0.45 microns, 0.3 microns, and 0.2 microns, and escherichia coli with a nominal pore size of 0.65 microns.
7. The membrane is resistant to high temperatures of 120 degrees, flammable, not resistant to acids and alkalis, and not resistant to solvents. It is only suitable for aqueous solutions (PH2-10), oils, air, fruit juices, and wines, etc. Whether the filter material is suitable for the filter membrane before use should be well noted.
8. When the filter residue is below 0.025 microns, it is not advisable to use a microporous membrane to filter. It only has an adsorption effect on heat source viruses and cannot be completely removed.
9. When the filter is used, the original air inside the filter should be discharged when the material liquid enters the filter, otherwise, the filter speed will be affected.
10. Pay attention to problems when using natural pressure, pressurization, vacuum, and negative pressure to prevent bacteria and particles in the outside air from inhaling and polluting the filtrate when vacuuming. For pressure filtration, the faster the filtration rate, the faster the pressure, the faster the filtration rate. For high pressure, we should consider whether the main body of the filter is intact, generally not more than 0.3MPa/c㎡.
11. Put the filter membrane into the container, soak it in distilled water at about 70 degrees to make it wet for several hours (about 4 hours) and then wash it with distilled water once for use.