What Is the Role of Filter Membrane in the Syringe Filter?

As one of the most frequently used tools in experiments, the syringe filter brings much convenience, and here are three key parameters of a syringe filter.

1. Filter membrane material: such as nylon, polyethersulfone, polytetrafluoroethylene
2. Aperture: such as 0.22μm, 0.45μm, and 1-5μm, whether it’s for general chromatographic requirements, requirements for removing very fine particles, or pre-filtration.
3. Diameter: such as 13mm, 25mm, 47mm
The commonly used microporous filter membrane is generally a disc filter membrane, such as a 25mm disc microporous filter membrane, which can be used with a syringe filter connected to a syringe. For the 47mm disc microporous membrane, you can use it in the membrane filter, Buchner funnel, pressure vessel, etc. with the vacuum pump and pressure pump. There are also larger diameter microporous membranes, which also require corresponding clamps and pressure to be used together.

Today, starting from the core membrane materials, HAWACH discusses the performance and material of the membrane materials to make you choose easily and correctly. With the deepening of modern life science research, the role of experimental sample filtration in the entire experiment is becoming more and more important. However, there are many membrane materials on the market. How to choose membrane materials according to your own application needs? It is not easy for workers. For example, how to choose a syringe filter in LCMS, how to choose a filter membrane when the solvent is unknown, whether there is a universal membrane that can be used in the world, etc. All trouble the experimenters in daily experimental work.

Usually, we pay attention to several important parameters when selecting products based on applications. The key factors for investigation are sample throughput and applicable membrane materials. Here we focus on how to choose a suitable filter membrane material. The membrane material is the “active” part of the filtration product or the part where the product plays a role. Understanding the characteristics of membrane materials can help us choose the most suitable filter material.

hydrophilic ptfe membrane filter hydrophobic ptfe membrane filter hydrophobic membrane and hydrophilic membrane

The following is a summary of commonly used membrane materials on the market.

1. Hydrophilic filter membrane material
1.1 Hydrophilic polypropylene membrane
Polypropylene membrane is a kind of “universal” membrane with a wide range of applications. Its hydrophilic properties make it applicable to the filtration of aqueous solutions as well as the filtration of organic solutions. This polypropylene membrane has strong chemical compatibility and is more commonly used in environmental testing and applications that require exposure to organic solvents. Its performance has been tested and verified in the application of HPLC (High-Performance Liquid Chromatography), this kind of membrane will not cause the contamination of the test sample due to the eluate in use. This feature also eliminates the possibility of contamination of the sample caused by the leachate of the membrane.

The self-fluorescence value of the polypropylene membrane is very low, so it will not increase the background “noise” in the application of distinguished fluorescence detection. It is also a non-adsorbent membrane that can prevent the non-specific binding of target molecules. There are two pore sizes of 0.2μm and 0.45μm to choose from.

The scope of application includes:
• Strong organic solvents required
• High-throughput screening
• Receptor: Ligand Screening
• Compound library screening
• HPLC sample preparation
• Shearing reaction
• Metabolism research
• Routine sample preparation

1.2 Hydrophilic polyethersulfone membrane
It is optimized specifically for the needs of biological, pharmaceutical industries and sterilization filtration. PES membrane has low protein binding properties and is a good choice for the recovery of trace samples. It has a wide range of drug compatibility and moderate chemical resistance/compatibility. Its characteristics include high flow rate, high throughput; low protein adsorption; high temperature and high-pressure sterilization; low dissolution; and high consistency. PES membranes are available in pore sizes of 0.1μm, 0.2μm, 0.45μm, 0.8μm and 1.2μm.

The scope of application includes:
• Screening for neonatal metabolic diseases
• Application based on microsphere/resin
• Receptor: ligand analysis
• Lysate clarification
• Routine sample preparation

1.3 Nylon membrane
Nylon membrane has a wide range of applications. Modification can be used to optimize the grade of the membrane. It can be used for high or low adsorption capacity, environmental atmospheric monitoring, and even sample preparation for chemical analysis. Nylon transfer membrane is a product optimized for the combination of biomolecules and is suitable for radiological and non-radioactive detection systems. There is also a low absorption membrane, which is 25-50 times lower than the traditional nylon transfer membrane. Another kind is an acid rain detection membrane, which is also a clean membrane, which is very suitable for the preparation of analytical samples before HPLC analysis. Nylon membranes are available in pore sizes of 0.2μm, 0.45μm, 1μm, and 1.2μm.

The scope of application includes:
• Sample Preparation
• Environmental monitoring: used for acid deposition
• Bead-based analysis
• Drug combination research
• Recovery of nucleic acid samples in acrylamide gel