Membrane Selection Guide by Application  

Typical Applications

Type of Membrane

Benefits and References

Air Analysis

Particulate analysis

PCTE or PETE

Bromine and Chlorine

Silver (0.45µm)

Polyaromatic hydrocarbons

Silver

Silica (crystalline), zinc oxide, cotton dust, chromic acid mist, oil mist, lead sulfide, nuisance dust, carbon black

PVC (0.8 and 5.0µm) 
Silver  (0.45 µm)

Cadmium, cyanides, lead, quartz in coal dust, welding and brazing fumes

MCE (0.8 µm)

Trace elements, for aerosols

PCTE or PETE  (0.2 – 8.0 µm)

Low trace elements contamination in
special aerosol membranes

Quartz/Silica

Silver 

NIOSH Methods S315, OML.

Zinc oxide fumes

Silver 

NIOSH Method S316.

Analytical Methods

Activation analysis

PCTE or PETE  

Minimal absorption of beta radiation
Low membrane trace elements.

Adsorbable organic halide (AOX)

PCTE (0.4 µm)

Low trace halides in membrane.

Densitometry

PCTE or PETE

Uniform transmissivity of light within same lot.

Emission spectroscopy

PCTE or PETE

Very low trace element background.

Gravimetric analysis

PCTE or PETE

Microchemical analysis

PCTE or PETE

• Microchemical tests can be made on the membrane.
• Excellent chemical resistance.

Qualitative analysis

PCTE

• Surface capture of sample in one plane.
• Low trace elements in membrane.

Radioactive monitoring and analysis

PCTE or PETE

• Accurate, consistent measurements of low energy alpha and beta emissions from sample.
• Corrections for filter absorption eliminated.
• Best for fractionating radiocolloids.

X-ray diffraction

Silver

Minimum of interfering spectra.
NIOSH Method 7500, 7501, 9000

X-ray fluorescence

PCTE or PETE

• Membrane can be used for the target.
• Low trace elements-no characteristics radiation.
• Ideal for combined SEM/X-ray fluorescence analysis.

Blood Analysis / Filtration

Plasmapheresis

PCTE or PETE (0.6 or 0.8 µm)

• Low hemolysis due to smooth membrane surface.
• Low non-specific binding of proteins.

Red blood cell deformability

PCTE  (4-7 µm)

Thinness and capillary pores of membrane allow near in-vivo measurements without hemolysis.

Red blood cell filtration

PCTE (8.0 µm)

Low hemolysis due to smooth membrane surface.

Cell / Tissue Culture

Studies of cells, Cell culture

PCTE or PETE (0.4 – 5.0 µm)

• Near in-vivo conditions
• High diffusion rate.

Prefiltration of tissue culture media

Glass fiber filter, syringe filters

• High dirt loading capacity
• Low cost.

Sterile filtration of tissue culture media

MCE, Nylon or syringe filters (0.1 and 0.22 µm)

• Absolute removal of microorganisms.
• Excellent throughput.

Chemotaxis

Chemotaxis

PCTE

• Rapid cell migration.
• Reduced incubation times.
• Sterilization not necessary

Cytology

Cytology

PCTE
(3.0, 5.0, 8.0 µm)

• All cells are in focus.
• Membrane does not stain.
• Resistant to alcohols, stains and xylene.
• No cell loss, cellular distortion, nor cell lysing.
• No RBCs, proteins, or cellular debris in specimen.
• High strength allows less critical handling.
• Simpler microscopic analysis.
• High flow rates minimize cell damage.

General Filtration

Prefiltration and coarse clarification

Glass fiber filter

• High dirt loading capacity.
• Low cost.

Beverage stabilization

MCE or Nylon (0.45 – 1.2 µm)

Absolute filtration.

Particulate and bacterial removal

PCTE, MCE, Nylon (0.1 – 5.0 µm)

Absolute removal.

Finish clarification

MCE or Nylon  (0.22 – 1.0 µm)

• High dirt loading capacity.
• Absolute filtration.

Fuel testing

MCE (0.45, 0.8 µm)

ASTM D2276

Liposome extrusion

PCTE (0.03 – 0.4 µm)

• Consistency of vesicles.
• Faster than other methods.

Sterilizing filtration

PCTE, MCE, Nylon(0.1 – 0.22 µm)

Absolute removal of bacteria.

Serum filtration

MCE or Nylon (0.1 and 0.22 µm)

• Absolute removal of microorganisms.
• Relatively high dirt loading capacity.

Forensic

Gunshot residue test (GSR)

PETE (0.4 and 0.6 µm)

• Surface capture in one plane.
• Excellent chemical resistance.

Microscopic examination of samples

PCTE or PETE (0.4 µm)

Surface capture in one plane of focus.

HPLC Solutions Filtration

HPLC solutions filtration

PETE, PTFE or syringe filters (0.4 µm)

• Excellent chemical resistance.
• High flow rates.

Microorganism Studies and Analysis

Concentration

PCTE or PETE (3.0 – 5.0 µm)

Low non-specific binding of microorganisms

Fractionation

PCTE or PETE

Low non-specific binding of microorganisms

Cryptosporidium

PCTE

Surface capture.

Giardia lamblia

PCTE (5.0 µm )

Low background clutter.

Harvesting

PCTE or PETE

• Surface capture of microorganisms.
• Ability to backwash for harvesting.

Observation

PCTE or PETE (0.2 – 0.8 µm)

• Surface capture of microorganisms.
• Membrane is non-staining.

Direct Total

Microbial Count

PCTE (0.2 – 5.0 µm)

See Epifluorescent Microscopy under MICROSCOPY.

Dirofilaria immitis

PCTE (5.0 µm)

• Surface capture of microfilaria.
• Membrane does not stain.

Legionella

PCTE (0.2 µm)

Low non-specific binding

Shistosoma haematobium

PCTE (12.0 - 14.0 µm)

Surface capture.

Sterility testing

MCE (0.22 and 0.45 µm)

21 CFR436

Total and fecal coliform

MCE (0.45 and 0.7 µm)

Standard Methods/Water and Waste water, 17 ^th Ed.

Yeasts and molds

PCTE (black), (0.6 and 0.8 µm)

• Surface capture of sample.
• Membrane does not stain.

Microscopy

Direct optical observation

PCTE or PETE (0.2 and 0.4 µm)

• Samples are collected in one plane, in focus.
• Superior morphologic resolution.
• Excellent chemical compatibility.
• Membrane does not stain.
• No clearing of membrane necessary.
• Simpler slide preparation.
• Uniform sample deposition.
• Minimum autofluorescence.
• Standard Methods/Water and Waste Water, 17 ^th Edition.
• ASTM D4455-85, D4454-85, and F1095-88.

Electron microscopy

PCTE (0.1 – 5.0 µm)

Epifluorescent microscopy

Bacteria total count and observation.

Yeast total count and observation.

Spore observation

Black PCTE

0.2 – 5.0 µm
0.6 and 0.8 µm
5.0 µm

Nucleic Auto Studies

Alkaline elution

PCTE (0.8 – 2.0 µm)

• Does not absorb DNA.
• DNA is retained intact.

Filtration of DNA fragments

PCTE (0.2 µm)

Single strand passes through filter without breaking.

Pharmaceuticals

Small volumes

Syringe filters

Convenient.

Prefiltration

Glass fiber filter

Inexpensive and high dirt loading capacity.

Sterilization

MCE, Nylon (0.1 – 0.22 µm)

• Absolute retention.
• 21 CFR 210 and 211.

Virus or Protein

Concentration / separation / fractionation / purification

PCTE or PETE (0.01 – 0.1 µm)

Low non-specific binding of viruses and proteins.

Observation

PCTE or PETE (0.01 and 0.03 µm)

Direct observation of viruses by epifluorescent microscopy.

Water Analysis / Filtration (See also Microorganism Studies and Analysis)

Organic halides (AOX)
Low Chlorine    

PCTE (0.4 µm)

Undetectable halides from membrane in residual ash.

Nitrates, nitrites phosphates and ammonia, Low extractable

PCTE (0.4 µm)

Does not leach out chemicals of interest from membrane.

Culturing of microorganisms

MCE (0.2 – 0.8 µm)

Standard Methods/Water and Waste Water, 17 ^th Edition.

Direct count of microorganisms

Black PCTE (0.4 – 5.0 µm)

See Epifluorescent Microscopy under MICROSCOPY.