The Avestin EmulsiFlex B15: The Improved French Press

by biopharmacharis in Biopharma Process Systems, BPS News, BPS Right Sidebar Content

The Avestin EmulsiFlex B15: The Improved French Press

The French pressure cell press, also known as the French press, is a cellular disruption unit invented by Charles Stacy French, utilised to disrupt the plasma membrane of cells by forcing them through a narrow orifice at very high pressure. This forced passage is implemented via a hydraulic pump, driving a piston within a larger cylinder that contains the liquid sample [1]. As the cells exit the orifice at the other end, shear and cavitation forces break open the cells, releasing their contents; the degree of shear and cavitation can be carefully adjusted by regulating the piston pressure. 

The French press design allows a single pass through the point of maximum shear force; preserving the integrity of delicate intracellular products.

Avestin’s B15 high pressure homogeniser is widely regarded as the improved French press, with its impressive capability in allowing adjustable, consistent homogenising pressures of up to 45,000 psi, making it suitable for even the toughest of samples. With a sample capacity of 3-15mL (batch), the B15 is especially well-suited for small volume and/or high value samples, and is widely implemented across the biotech, pharma and food industries.

The unique Emulsiflex design ensures there are no ‘O’-rings or gaskets in the entire path of the product; this means less risk of contamination, easier cleaning and no leakage. The unique ‘dynamic’ homogenising valve design allows movement in accordance with sample viscosity; reducing the risk of blockage. The design is an aid in overcoming many of the blockage issues associated with fixed valve design, allowing for smoother, efficient processing.

The Avestin B15

The pneumatically-powered B15 design ensures that no electrical power is required for functionality. Furthermore, the unique pump design ensures near-silent operation.

Sample capacity: 3 mL – 15 mL batch

Common applications of the B15 include:

  • Cell disruption
  • Emulsification
  • Particle size reduction
  • Unilamellar liposome preparation


For more information on the Avestin benchtop range, or for any information on the pilot/production scale machinery, visit: or contact our Avestin product specialist, Ashley Morgan, | +44 (0)1962 841092


  1. Vanderheiden GJ, Fairchild AC, Jago GR (May 1970). “Construction of a laboratory press for use with the French pressure cell”Appl Microbiol. 19(5): 875–7.