Technical data and application of tangential flow filtration system

Whether in food, pharmaceutical or biological industries, purification is a crucial step related to product quality. There are many purification methods, including chromatography, centrifugation, dialysis and so on. In fact, another filtering technology is quietly emerging, that is tangential flow filtering (TFF).

So, what kind of technology is tangential flow filtration? It can be understood through a simple experiment. Suppose you have a pile of pebbles and sand that you need to separate. You might say, that's not easy. Just find a sieve. In fact, things are not as simple as imagined.

When small sand particles fall through the screen, a pebble layer will be formed on the screen surface to prevent the sand particles at the top from passing through. This is dead end filtration. At this time, remind you to shake gently. In fact, this is the principle of tangential flow filtration. The vibrating screen releases the pebbles blocking the screen, so as to make the sand on the top pass faster.

For traditional filtration, because the flow direction of the liquid is perpendicular to the surface of the filter membrane, this method is also called dead end filtration. The opposite is tangential flow filtering, also known as cross flow filtering. As the name suggests, the flow direction of the liquid is parallel to the surface of the filter membrane.

Because the tangential flow continuously "washes" the surface of the filter membrane during the filtration process, this operation mode effectively alleviates the accumulation of large particles and molecules on the membrane, so it can separate and purify biomolecules more quickly and efficiently. Its advantages are as follows: compared with dialysis, the assembly is easier and the processing speed is much faster; Compared with centrifugal concentration device or stirred ultrafiltration device, higher concentration can be obtained in a shorter time.

This technology is widely used in biology, pharmacy and food industry. It can be used for the concentration and desalination of proteins, peptides or nucleic acids, the separation of biomolecules of different sizes, the collection of cell suspension, and the clarification of fermentation broth and cell lysate.