Laboratory Filtration Selection Guide

Laboratory Filtration Selection Guide

Selecting a Filter    Filtration Guide     Membrane Materials    Terms

Selecting a Filter

  1. Determine the particle size to be retained or filtered. Membranes will retain all particles equal to, and then larger than their designated pore size.
  2. Assess the chemical compatibility of the membrane filter with the liquid or gas to be filtered. Consider the chemical resistance properties of the all parts that will contact the filtrate.
  3. Depending on the procedure performed, the membrane color or surface pattern may be important.
  4. Also consider hydrophilic or hydrophobic membranes; temperature, flow rate, throughput, and sterilization needs.

Filtration Guide

Use this general guide to determine the optimal type of filtration for your particle sizes. Each type of filtration is designed to separate differing ranges of microparticles and particles:

  • ultrafiltration is best with particles of roughly 10,000-1,000,000 MW; microfiltration is best with particle sizes of roughly 0.1-10 µm;
  • macrofiltration is best with particle sizes greater than 50 µm.
Type of filtration Ultrafiltration Microfiltration Macrofiltration
Units Dalton (MW) Microns (Ωm) 50 Ωm or greater,
visible to the human eye
Particle examples
and sizes
Trypsin (24,000)
Serum alburmin (67,000)
Gamma globulin (169,000)
Viruses (600,000 to 30,000)
Endotoxins (500,000 to 12,000)
Mycoplasm (0.08 to 0.4)
proteins (0.0005 to 0.5)
Fungi (0.7 to 3)
Yeast (0.6 to 4)
Bacteria (0.3 to 12)
human hair

Disclaimer: Cole-Parmer products are not approved or intended for, and should not be used for medical, clinical, surgical or other patient-oriented applications.