Track Etch Membranes (TEMs) are produced out of either Polycarbonate or Polyester polymers. TEMs are quite unlike other conventional membranes that use "tortuous-path" structures and tend to have a wide distribution of pore sizes. As can be seen from the accompanying photo, TEMs have distinct pores.

TEMs are manufactured in a two step process. In the first step, the polymer is exposed to radiation treatment in a nuclear reactor (tracking). As the particles pass through the polymer, they leave sensitized tracks. In the second step, the tracks left by the particles are etched, or disolved, into cylindrical pores.

For more reading:

Expanding the use of track-etched membranes

Cheryan, Munir, Ultrafiltration and Microfiltration Handbook, p.52-54

Sterlitech Polycarbonate (PCTE) and Polyester (PETE) membranes are available in pore sizes ranging from 0.01 micron to 20 microns and are available as either cut discs or flat sheets.

Major Benefits of TEMs are:

• Flat, smooth, glass-like surface for sample capture
• Transparent surface
• Lowest, non-binding membrane
• Excellent chemical resistance and thermal stability

Applications of TEMs can be categorized into three groups: process filtration, cell culture, and laboratory filtration.

Process Filtration: Applications include filtration of groundwater and removal of specific sized particles in process applications.

Cell Culture: TEMs are neutral biologically, being neither cytoxic nor bactericidal. Cells can be cultured on both sides of the membrane in a holder or inserts. The optical transparency of the membrane allows for direct observation of the cells.

Laboratory Filtration: Applications include epfluorscent microscopy (also available in black), observation of large microorganisms in oceaonography, and environmental analysis.