With protein binding, it’s all about the syringe filter’s membrane material, performance and flow rate.
For example, syringe filters with a high protein binding membrane material will bind proteins, resulting in premature filter clogging.
On the other hand, low protein binding syringe filters are made from membrane materials that don’t absorb proteins. These filters are designed to minimize protein sample loss and provide great performance and flow rates.
This difference in protein binding must be factored in when deciding which type of syringe filter you need for your application.
Protein Binding Overview
Protein binding refers to the ability of proteins to form bonds with other substances. These substances can be other proteins, molecules, or other compounds.
Protein concentration in a solution can be high binding or low binding, depending on the amount of particulate it contains.
A high protein concentration is more difficult to filter, often requiring a prefilter or multiple filters to process.
A low protein concentration is easy to filter. However, to avoid binding to filter media or other components, low protein binding syringe filters are required to minimize protein loss during filtration.
Protein Binding Characteristics of Syringe Filters
The membrane material of the syringe filter dictates how it binds protein.
The manner in which materials bind protein range from low to moderate to high protein binding.
When determining which syringe filters are best for your applications, consider these two factors:
- The degree of filtration you need;
- The fluid characteristics of your samples.
Then, match your filtering needs with the protein binding characteristics of these syringe filter materials:
- Cellulose Acetate (CA) – Very low protein binding;
- Glass Fiber and Glass Fiber Multilayer Prefilter – Low protein binding, use multilayer prefilter to prevent clogging of high protein solutions;
- Nylon and Nylon Multilayer Prefilter – Low to moderate protein binding;
- Polyethersulfone (PES) and PES Multilayer Prefilter – Very low protein binding;
- Polypropylene (PP) – Low protein binding;
- Polytetrafluoroethylene (PTFE), hydrophilic PTFE, and PTFE Multilayer Prefilter – Low protein binding;
- Polyvinylidene Fluoride (PVDF) and hydrophilic PVDF – Low protein binding;
- Regenerated Cellulose (RC) – Very low protein binding;
- Anopore – Low protein binding.
Additional Syringe Filter Considerations
As you can see, there are numerous options for low protein binding syringe filters, so other factors need to be taken into consideration.
One key consideration is application or how you plan on using the filter. This chart can help you narrow your choices of low protein binding syringe filters.
|If you’re doing:||Then this type of filter is best:|
|Coarse particle removal||Glass Fiber, CA|
|Filtering culture media containing sera||CA|
|Filtering cell culture media||PES|
|Aqueous solution clarification, sterilization, ultracleaning||CA, Glass Fiber, Nylon, PES, PP, PVDF, RC, Anopore|
|Ultracleaning, clarification of solvents||Nylon, PTFE, RC|
|Filtering protein-free culture media||Nylon|
|Filtering gases||PVDF, PTFE|
Other considerations when selecting low protein binding syringe filters are the syringe filter connection, pore size, diameter of the filter’s membrane, and sterility.
Still Have Questions?
Get more information from our filtration guides and charts here.
If you still aren’t sure what you need, contact us via email, phone, or support ticket here.