Syringe filters do not require membrane changes and filter cleaning, eliminating the complicated and time-consuming preparations, which are widely used in laboratories. It is mainly used for pre-clarification, particle removal, sterilization and filtration of samples.
Factors to consider when choosing a syringe filter
When the syringe filter is used to process the chromatographic sample, it is necessary to avoid the introduction of other impurities in the filtration process. The appearance of such impurities may be: the shell material or the filter membrane which will shed particles and be brought into the filtrate. Therefore, the materials of the filter membrane and the shell structure are very important. Different types of filter membranes are suitable for samples of different properties.
1) Hydrophilic sample: use a hydrophilic membrane, which has affinity for water and is suitable for filtering water-based solutions. Available filters are mixed cellulose ester, polyethersulfone (PES) Nylon, etc.
2) Strongly corrosive organic solvents: generally choose hydrophobic membranes, such as PTFE, polypropylene (PP) and other filter membranes.
3) Ion chromatography: PES membranes are generally considered to be more suitable for the filtration of solutions with low inorganic ions.
When selecting a syringe filter, in addition to the above factors, the volume of the sample must also be considered. Usually, when the sample volume is less than 2ml, a 4mm diameter micro filter is selected; when the sample volume is between 2-10ml, a 13mm diameter filter is selected. When the sample volume is greater than 10ml, select a 25mm diameter syringe filter.
If the syringe filter is used frequently, don't forget to maintain it. Here are some maintenance methods of the syringe filter.
1. According to the actual use frequency, periodically remove the filter material in the primary effect syringe filter to clean.
2. When it is found that the wind speed is small, first check whether the surface of the primary effect air filter is black. If it is black, it means that the pre-filter has more dust and the resistance increases, that is, the non-woven inside the primary effect filter should be removed. Clean or replace the cloth.
3. When the non-woven fabric is changed or cleaned, the wind speed cannot be increased, which means that the air filter has been blocked and the resistance has increased, so the syringe filter should be replaced.
4. When replacing the syringe filter, remove the spray plate, take out the filter, and replace the new air filter according to the specifications and models of the original syringe filter. During installation, confirm the arrow mark on the syringe filter, and the arrow should point in the direction of air flow, and ensure a good seal to prevent leakage.
5. After the syringe filter is replaced, it is necessary to confirm that there is no leakage in the frame, and use a dust particle counter to detect it, and it can work normally after reaching the technical index.
Advantages of HAWACH syringe filters
1. Hygienic polypropylene material is used for the housing material of syringe filter.
2. The precise design of the product structure ensures smooth filtration, rationalized internal space and low residual rate, thereby reducing the waste of samples.
3. The edge part is provided with thread, which plays a non-slip effect, and the user-friendly design makes the operator handy.
4. Cooperate with international well-known filter manufacturers to provide protection for instruments and chromatographic columns.
5. Stable filter membrane quality, zero batch-to-batch variability, which ensure the consistency of the analysis results.
The above is the introduction of the selection and maintenance method of using the syringe filter. If you have any questions, welcome to contact HAWACH.