Membrane Filters

Chrom Tech Membrane Filters

Chrom Tech membrane filters help minimize particle carryover during sample preparation—reducing the risk of clogged flow paths, unstable backpressure, and instrument downtime. By filtering samples before injection, you protect sensitive LC components and support consistent, reproducible results.

We offer a wide selection of precut membrane discs in Nylon, Cellulose Acetate (CA), PVDF, PES, Nitrocellulose, and PTFE to match common solvent systems and analytical workflows.

  • Disc sizes from 13 mm to 142 mm
  • Common pore sizes: 0.2 µm and 0.45 µm
  • Standard offering: non-sterile

Not sure which membrane is best for your sample matrix or solvent? Email support@chromtech.com for selection help or a quote.

Membrane Selection Guide
Membrane Aqueous Organic Low Protein
Binding
Application
Nylon   General laboratory and HPLC sample filtration prior to injection. Solvent resistant with low extractables; not ideal when protein recovery is critical.
PTFE     Hydrophobic and chemically resistant to most solvents, acids, and bases. Low extractables; can block water vapor (useful for transducer protection).
PVDF Solvent resistant membrane with low UV-adsorbing extractables. Used for HPLC sample filtration and general biological filtration; low protein binding.
PES Mechanically strong with low inorganic extractables. Typical uses include ion chromatography, tissue culture filtration, and filtration of proteins and nucleic acids.
Cellulose Acetate   Very low protein binding (often less than PVDF) and ideal for aqueous samples. Excellent when maximum protein recovery in filtrate is critical.
PP   Hydrophilic membrane with broad chemical compatibility to many organic solvents. A strong choice for HPLC sample filtration in protein analysis workflows.
RC Regenerated Cellulose is hydrophilic, solvent resistant, and low protein binding. Ideal for removing particulates from HPLC samples prior to injection; low water extractables.
NC     Nitrocellulose (mixed esters) filters are hydrophilic and made from cellulose nitrate/cellulose acetate blends. Fast flow rates due to a uniform membrane structure.
Legend: ● = compatible / recommended.

Key Definitions
Membrane Filter
A thin, porous filtration medium used to remove particulates or microorganisms from liquids prior to analysis, protecting HPLC systems and improving reproducibility.
Pore Size
The nominal diameter of membrane openings, commonly 0.2 µm or 0.45 µm, which determines the size of particles retained during filtration.
Hydrophilic vs Hydrophobic Membranes
Hydrophilic membranes readily wet with aqueous solutions, while hydrophobic membranes (such as PTFE) are designed primarily for organic solvents unless pre-wetted.
Prefilter
A coarse upstream layer that captures larger particles before they reach the main membrane, extending filter life and improving throughput for dirty samples.
Hold-Up Volume
The residual liquid volume retained inside a filter after use, which can impact sample recovery in low-volume analytical applications.
Frequently Asked Questions
Why should I filter samples before HPLC analysis?
Filtering removes particulates that can clog injector ports and column frits, helping maintain stable pressure, extend column life, and improve reproducibility.
Should I use 0.2 µm or 0.45 µm membranes?
Use 0.2 µm membranes for finer particulate removal and sensitive UHPLC systems. Use 0.45 µm membranes for general filtration when flow rate and throughput are priorities.
Which membrane material should I choose?
Nylon works for most aqueous or organic samples, PTFE is ideal for organic solvents, PVDF supports mild organic and aqueous solutions, and hydrophilic PTFE handles mixed solvent systems.
When should I use a membrane with a prefilter?
Prefilters are recommended for samples with higher particulate load, as they capture larger debris first and prevent premature clogging of the main membrane.
Are Chrom Tech membrane filters sterile?
Standard membrane filters are supplied non-sterile. Sterile and certified options may be available by request depending on membrane type and configuration.