In-line mobile phase filters

Guide to…Syringe Filter Properties

Identifying the filter material most suitable for your application based upon the nature of the liquid or gas you are filtering will ensure the best performance of your filter. Each syringe filter contains a membrane filter of a set diameter and plastic housing with luer connections used for connecting to syringes (or in-line hosing systems).

The membrane filter material has differing chemical and physical properties such as hydrophobicity, flow rate, extractables and protein retention making them suited to differing applications. Once you have selected the most compatible filter material, you will need to consider what pore size is most appropriate for your application and what diameter filter is suitable for your sample volume. 

Membrane Material

Filter diameter 

High particulate loaded samples with tend to block the pores in the membrane more quickly so the total volume you can filter through a certain diameter syringe filter will vary greatly. Please take the below figures as a guide only.

• 13mm diameter - for samples <10ml
• 25mm diameter - for samples <100ml
• 33mm diameter - for samples <250ml 

For samples that are very particle ladden, it is recommened that you try pre-filtering your sample. Pre-filtering can be achieved with a number of different filters, such as glass microfibre. Some syringe filters come with an in-built pre-filter.