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Asymmetric Flow Field-Flow Fractionation

Asymmetric Flow FFF is a subcategory of Flow FFF. Postnova Analytics has been setting the standard in this area since the beginning. The company developed and introduced the first Flow FFF instrument (Model F1000) in 1986, launched the first commercial automated Asymmetric Flow FFF (Model HRFFF-10.000) in 1997, first Dual-Pump Focusing Asymmetric Flow FFF in 2004 and finally invented and presented the first temperature controlled Mid and High Temperature Asymmetric Flow FFF in 2004. 

In Asymmetric Flow FFF the separation force is generated by a cross flow field inside the channel. The cross flow is divided from the main flow, pumped through the channel and is directed through a semi-permeable membrane which is located at the bottom wall. The membrane pores size prevents the sample to pass through but allows the solvent to exit the channel easily. The sample fractions are eluted out of the channel in direction to the detectors by the remaining channel flow.


AF2000 AT (Ambient Temperature)

This is the standard Flow FFF which works at ambient temperatures and is available as aqueous metal-free, stainless steel and multisolvent version.

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AF2000 MT (Mid Temperature)

The AF2000 MT is ideal for the use in higher level research as well as commercial-industrial applications. The main area of its usage is product development, manufacturing and quality control.

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AF2000 HT (High Temperature)

The most important Asymmetric Flow Field-Flow Fractionation technique for the characterization of polymers at elevated temperatures is High Temperature Asymmetric Flow Field-Flow Fractionation (Asymmetric Flow FFF) which was invented and developed by Postnova Analytics and Dow Chemical in a joint research project.

Unique Features:

  • Ceramic Membrane Channel Cartridge
  • Broad Molar Mass Separation Range at High Temperatures
  • Gentle Separation Conditions

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EAF2000 (Electrical FFF)

This new technology combines Asymmetric and Electrical Flow FFF in one system and can be combined with any existing AF2000 system already in use. Now, Electric and Cross Flow Fields can be applied in one FFF channel.

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