August 07, 2018

Membrane filtration: A guide to choosing membranes

By Jill Herrera, Global Product manager

Not all membranes and solvents mix well. Read this quick guide and choose the most suitable membrane for your application based on chemical compatibility.


Membrane-sample Compatibility

It’s easy to overlook membrane compatibility when picking out your filter or device for your sample filtration.

Good membrane-sample compatibility supports efficient filtration and minimizes resistance, while poor compatibility might result in backpressure, ineffective filtration, or even chemical attack of your membrane, leading to contamination of your filtrate.

Here, we’ve created a quick reference membrane filtration guide, listing membranes’ compatible (and incompatible) solvents, helping you choose the most appropriate membrane for your sample.

Polytetrafluoroethylene (PTFE) Membrane

Hydrophobic, highly inert, and durable, PTFE is a popular material with a wide operating temperature range and resistance to the damaging effect of many chemicals.

When should you use it?

DO USE: for filtering solvents and other aggressive chemicals, such as acetone and DMSO.

MAYBE USE: when you need to filter aqueous solutions and sodium hydroxide. You’ll need to pre-wet with a water-miscible solvent, such as methanol, to overcome the hydrophobicity of the membrane.

Polyvinylidene Fluoride (PVDF) Membrane

Another material resistant to a broad range of organic solvents, PVDF is naturally hydrophobic but can be modified to a hydrophilic state.

When should you use it?

DO USE: for aqueous and non-aggressive solvent-based chemicals, such as amyl alcohol, chloroform, and formic acid.

DO NOT USE: for bases, acetone, dimethyl formamide, methyl ethyl ketone, and pyridine.

Nylon (NYL) Membrane

Naturally hydrophilic with wide chemical compatibility and good resistance to organic solvents. Nylon is particularly suitable for high-pH samples but should be avoided in any protein recovery applications.

When should you use it?

DO USE: for filtering aggressive solutions such as alcohols and DMSO.

DO NOT USE: with acids and some other chemicals including butyl chloride, chloroform, chlorobenzene, cresol, cyclohexanone, cyclohexane, methylene chloride, and trichloroethylene.

Polyethersulfone (PES) Membrane

Hydrophilic and suitable for filtering aqueous and some organic solvents in a variety of environments. PES is well suited for high-pH applications.

When should you use it?

DO USE: for non-aggressive aqueous solutions and biological fluids, including some alcohols, acetic acid, ammonia, benzene, citric acid, formaldehyde, hydrochloric acid, and sodium hydroxide.

DO NOT USE: for filtering acetonitrile, amyl or benzyl alcohol, DMSO, nitric or sulfuric acid, or phenol.

Polypropylene (PP) Membrane

Available in a membrane and non-woven formats, polypropylene is slightly hydrophobic and resistant to a broad range of chemicals and temperatures.

When should you use it?

DO USE: for aggressive filtration applications and solvents such as butyl alcohol, DMSO, methanol, and sodium hydroxide.

DO NOT USE: with benzene, butyl chloride, carbon tetrachloride, cyclohexane, ethers, and nitric or sulfuric acid.

Cellulose Acetate (CA) Membrane

Hydrophilic filtration membrane with limited chemical resistance but made from pure cellulose acetate, which is very low protein binding and so excellent for protein recovery. Withstands temperatures up to 180°C, making it well suited for hot gases.

When should you use it?

DO USE: for aqueous solutions and low molecular weight alcohols, such as benzene, boric acid, butyl alcohol, ethanol, hexane, isopropyl alcohol, methanol, pentane, perchloro ethylene, and water.

DO NOT USE: for acetic acid, acetonitrile, chloroform, cyclohexane, DMSO, ethyl acetate, hydrochloric and hydrofluoric acid, nitric acid, sodium hydroxide, and trichloroethane.

Cellulose Nitrate (CN) Membrane

Hydrophilic membrane with limited resistance to organic solvents, but is strong and flexible, with a high flow rate. Cellulose nitrate is compatible with some solvents that cellulose acetate is not.

DO USE: for acetic acid, carbon tetrachloride, chloroform, cresol, and phenol.

MAYBE USE: for ethers, ethylene glycol, formic acid, isobutyl and isopropyl alcohol, methyl chloride, and trichloroethane.

DO NOT USE: with a similar list of solvents as cellulose acetate, but also avoid ethanol and methanol.

Regenerated Cellulose (RC) Membrane

A versatile cellulose-based hydrophilic membrane that is resistant to a very large range of solvents, including aqueous solutions and organic solvents. Recommended for use in HPLC and protein recovery applications.

DO USE: with most common solvents, including those used in HPLC.

DO NOT USE: with strong acids, such as acetic acid, hydrochloric and hydrofluoric acid, nitric acid, sulfuric acid, and also sodium hydroxide.

Anopore (ANP) Membrane

Hydrophilic membrane with excellent range of chemical compatibility. Anopore also has a very consistent honeycomb-structured distribution of pores and becomes almost transparent when wet, making it suitable for microscopy studies.

When should I use it?

DO USE: for most common solvents, including aqueous and organic.

DO NOT USE: with ammonia and strong acids or bases, including hydrochloric and, sodium hydroxide, and sulfuric acid.

Glass microfiber (GMF) Membrane

A depth filter, glass microfiber is made from 100% borosilicate glass, highly inert, and often used as a prefilter. It’s resistant to temperatures up to 500°C and a very wide range of solvents.

When should I use it?

DO USE: with most of common solvents, including aqueous and organic, strong acids and bases.

DO NOT USE: with hydrofluoric acid or sodium hydroxide, and bear in mind a limited resistance to ammonia.

Charting compatibility

Hopefully, this quick overview helps you identify the most appropriate membrane-solvent combination for your application.

To compare between all the common membranes and solvents, review the chemical compatibility chart in our guide to laboratory membrane filtration principles and chemical compatibility.

You might also find it useful to follow our quick reference chart (below) or try our filter selector tool to find your membrane filter fast.

If you have any questions about any aspect of your filtration process, contact GE Healthcare Life Sciences support or your local representative.