Syringe filters are common consumables in laboratories, mainly used for sample prefiltration and particle removal. On the one hand, it can effectively protect the chromatographic system and reduce the maintenance cost of the instrument. On the other hand, it does not need to replace the filter membrane and clean the filter, eliminating the complicated and time-consuming preparation work, and is widely used in experiments.
In order to meet the needs of different customers in filtration products, there are many types of commercial lab syringe, with different filter diameters, pore sizes, and membrane materials. So how to choose a suitable disposable syringe filter product? In response to this problem, HAWACH will give you tips and help you choose a suitable syringe filter in three steps.
Step 1: Select the diameter of the filter according to the sample volume to be filteredIf the sample volume is less than or equal to 2ml, select the filter type injection bottle
Step 2: Select the pore size according to the nature of the sample and the chromatographic method The recommended filter pore size is 0.45μm: the particle size of the column packing is above 3μm; viscous samples or samples with high particle content
The recommended filter pore size is 0.22μm: the particle size of the column packing is below 3μm; the liquid sample before UPLC and LC/MS analysis.
Step 3: Select the type of filter membrane according to the characteristics of the sample and the filter object.Before introducing the selection of filter membranes, let us first learn a few key words to evaluate the suitability of the filter membrane.
Chemical solvent resistance: it refers to the degree of resistance of the filter membrane material to chemical solvents. If the filter membrane material does not tolerate a certain chemical solvent, it is easy to dissolve during the filtration process.
Dissolved matter: In the process of filtering, it may bring in the interfering components introduced from the membrane, shell material, and production. This is the dissolvable matter. If the sample volume allows, you can discard the first 3-5ml solution to rinse the filter to reduce the amount of dissolution.
Compound adsorption: it refers to the phenomenon that the compound to be tested is adsorbed by the filter membrane during the filtration process.
Through these keywords, we can know that a suitable filter product needs to meet the following conditions: it can withstand the solvent of the sample, and the filter membrane has a low background of dissolving matter and low adsorption of the target compound. For the specific filter membranes to be used, choose it based on experience or contact HAWACH freely.
After selecting the product, in the actual testing work, you will still encounter other filtration problems, such as the high and low recovery rate after filtration, impurity peaks that do not know where to run out on the chromatogram... and so on. The instability of filter product quality troubles many users. Therefore, in addition to choosing a suitable filter product type, it is more important to choose a reliable filter manufacturer. HAWACH is a reliable and good partner to help your testing career.
HAWACH syringe filters are produced in a 100,000-class clean workshop, and strictly implement the ISO9000 quality standard system requirements. Our filtration products have undergone several tests to ensure quality stability, including: appearance test, HPLC background test, bubble point test, maximum pressure test, flow rate test, retention volume test, etc. Through such strict factory inspection, you can ensure that the filter you use can be cleaner, more stable, and more reliable.