|
Typical Applications |
Type of Membrane |
Benefits and References |
|
Air Analysis |
|
Particulate analysis |
PCTEor PETE |
· Samples are collected in one plane, in focus.
· Superior morphologic resolution.
· No clearing of membrane for most applications.
· Simpler slide preparation.
· Uniform sample deposition.
· Particles can be fractionated by discrete sizes. |
|
Bromine and Chlorine |
Silver
0.45um |
· NIOSH Method 6011 |
|
Polyaromatic hydrocarbons |
Silver |
· Reusable for economy |
|
Silica (crystalline), zinc oxide, cotton dust, chromic acid mist, oil mist, lead sulfide, nuisance dust, carbon black |
PVC
0.8 and 5.0um |
· Silica and contaminant free.
· NIOSH Methods 5000, 7505, 0500, 0600, 7601, 7502, 7500, 7602. |
|
Cadmium, cyanides, lead, quartz in coal dust, welding and brazing fumes |
MCE (Mixed Cellulose Esters)
0.8um |
· NIOSH Methods 7048, 7904, 7082, 7602, 7200 |
|
Trace elements |
PETE/PCTE for aerosols
0.2 – 8.0um |
· 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 for AOX
0.4um |
· Low trace halides in membrane. |
|
Densitometry |
PCTEor PETE |
· Uniform transmissivity of light within same lot. |
|
Emission spectroscopy |
PCTEor PETE |
· Very low trace element background. |
|
Gravimetric analysis |
PCTEor PETE |
· More accurate weight measurements.
· Matched weight filters not required. Tare weight not significantly affected by sample adsorption.
· Low, constant tare and ash weights.
· Non-hygroscopic. Tare weight not significantly changed by moisture adsorption.
· Reduced analysis time. |
|
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 |
PCTEor 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 S315. |
|
X-ray fluorescence |
PCTEor 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, 0.8um |
· Low h emolysis due to smooth membrane surface.
· Low non-specific binding of proteins. |
|
Red blood cell deformability |
PCTE for RBC deformability
4.7um |
· Thinness and capillary pores of membrane allow near in-vivo measurements without hemolysis. |
|
Red blood cell filtration |
PCTE
8.0um |
· Low hemolysis due to smooth membrane surface. |
|
Cell / Tissue Culture |
|
Studies of cells |
Cell culture
PETE/PCTE
0.4 – 5.0um |
· Near in-vivo conditions
· High diffusion rate. |
|
Prefiltration of tissue culture media |
Glass fiber filter,
MicroPrep syringe filters |
· High dirt loading capacity.
· Low cost. |
|
Sterile filtration of tissue culture media |
MCE, Nylon or MicroPrep syringe filters
0.1 and 0.22um |
· Absolute removal of microorganisms.
· Excellent throughput. |
|
Chemotaxis |
|
Chemotaxis |
PCTE for chemotaxis |
· Rapid cell migration.
· Reduced incubation times.
· Sterilization not necessary |
|
Cytology |
|
Cytology |
PCTE
3.0, 5.0, 8.0um |
· 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 – 1.2um |
· Absolute filtration. |
|
Particulate and bacterial removal |
PCTE, MCE, Nylon
0.1 – 5.0um |
· Absolute removal. |
|
Finish clarification |
MCE or Nylon
0.22 – 1.0um |
· High dirt loading capacity.
· Absolute filtration. |
|
Fuel testing |
MCE
0.45, 0.8um |
· ASTM D2276 |
|
Liposome extrusion |
PCTE
0.03 – 0.4um |
· Consistency of vesicles.
· Faster than other methods. |
|
Sterilizing filtration |
PCTE, MCE, Nylon
0.1 – 0.22um |
· Absolute removal of bacteria. |
|
Serum filtration |
MCE or Nylon
0.1 and 0.22um |
· Absolute removal of microorganisms.
· Relatively high dirt loading capacity. |
|
Forensic |
|
Gunshot residue test (GSR) |
Polyester
0.4 and 0.6um |
· Surface capture in one plane.
· Excellent chemical resistance. |
|
Microscopic examination of samples |
PCTE or PETE
0.4um |
· Surface capture in one plane of focus. |
|
HPLC Solutions Filtration |
|
HPLC solutions filtration |
PETE, PTFE or MicroPrep syringe filters
0.4um |
· Excellent chemical resistance.
· High flow rates. |
|
Microorganism Studies and Analysis |
|
Concentration |
PCTE or PETE
3.0 – 5.0um |
· Low non-specific binding of microorganisms |
|
Fractionation |
PCTE or PETE |
· Low non-specific binding of microorganisms |
|
Cryptosporidium |
PCTE |
· Surface capture. |
|
Giardia lamblia |
PCTE
5.0um |
· Low background clutter. |
|
Harvesting |
PCTE or PETE |
· Surface capture of microorganisms.
· Ability to backwash for harvesting. |
|
Observation |
PCTE or PETE
0.2 – 0.8um |
· Surface capture of microorganisms.
· Membrane is non-staining. |
|
Direct Total
Microbial Count |
PCTE
0.2 – 5.0um |
· See Epifluorescent Microscopy under MICROSCOPY. |
|
Dirofilaria immitis |
PCTE
5.0um |
· Surface capture of microfilaria.
· Membrane does not stain. |
|
Legionella |
PCTE
0.2um |
· Low non-specific binding. |
|
Shistosoma haematobium |
PCTE
12.0 - 14.0 um |
· Surface capture. |
|
Sterility testing |
MCE
0.22 and 0.45um |
· 21 CFR436 |
|
Total and fecal coliform |
MCE
0.45 and 0.7um |
· Standard Methods/Water and Waste water, 17th Ed. |
|
Yeasts and molds |
PCTE (black)
0.6 and 0.8um |
· Surface capture of sample.
· Membrane does not stain. |
|
Microscopy |
|
Direct optical observation |
PCTE or PETE
0.2 and 0.4um |
· 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, 17th Edition.
· ASTM D4455-85, D4454-85, and F1095-88. |
|
Electron microscopy |
PCTE
0.1 – 5.0um |
|
Epifluorescent microscopy
Bacteria total count and observation.
Yeast total count and observation.
Spore observation
|
Black PCTE
0.2 – 5.0um
0.6 and 0.8um
5.0um |
|
Nanowire & Nanotube Construction and/or Deposition |
|
Single Wall Carbon Nanotube
Contruction/Analysis |
PCTE |
· Uniform cylindrical pore size and shape.
· Membrane can be dissolved away with N-methyl-2-pyrrolidone, Methylene chloride, Chloroform.
· Strict pore size control of membrane allows for specific diameter of SWNT design.
· PCTE-developed nanotubes can provide better SERS enhancement than other common methods. |
|
Template for nanomaterial development for Surface-Enhanced Raman Scattering (SERS) |
PCTE |
|
Nucleic Auto Studies |
|
Alkaline elution |
PCTE
0.8 – 2.0um |
· Does not absorb DNA.
· DNA is retained intact. |
|
Filtration of DNA fragments |
PCTE
0.2um |
· Single strand passes through filter without breaking. |
|
Pharmaceuticals |
|
Small volumes |
MicroPrep syringe filters |
· Convenient. |
|
Prefiltration |
Glass fiber filters |
· Inexpensive and high dirt loading capacity. |
|
Sterilization |
MCE, Nylon
0.1 – 0.22um |
· Absolute retention.
· 21 CFR 210 and 211. |
|
Virus or Protein |
|
Concentration / separation / fractionation / purification |
PCTE or PETE
0.01 – 0.1um |
· Low non-specific binding of viruses and proteins. |
|
Observation |
PCTE or PETE
0.01 and 0.03um |
· Direct observation of viruses by epifluorescent microscopy. |
|
Water Analysis / Filtration (See also Microorganism Studies and Analysis) |
|
Organic halides (AOX) |
Low chlorine
PCTE
0.4um |
· Undetectable halides from membrane in residual ash. |
|
Nitrates, nitrites phosphates and ammonia |
Low extractable
PCTE
0.45um |
· Does not leach out chemicals of interest from membrane. |
|
Culturing of microorganisms |
MCE
0.22 – 0.7um |
· Standard Methods/Water and Waste Water, 17th Edition. |
|
Direct count of microorganisms |
Black PCTE
0.4 – 5.0um |
· See Epifluorescent Microscopy under MICROSCOPY. |