FeSSIF 101

What is FeSSIF?

FeSSIF (Fed State Simulated Intestinal Fluid) is a biorelevant test medium that replicates biliary secretions present in small intestinal fluid after eating food. Generating in vitro dissolution profiles of a Test Product and Reference in this fed state medium reveals what drug release rates would be like in vivo. If in vitro drug release profiles are complete, it is likely that this medium can be used to assess chances of achieving bioequivalence of a Test Product to the Reference.

What's  in FeSSIF?

After eating a meal, natural surfactants are secreted into the small intestine to help disperse fat in preparation for its digestion. FeSSIF contains the same types and levels of these physiological surfactants. These are critical because they form mixed micelles which can greatly enhance drug solubility and dissolution. This enhancement is especially relevant for BCS Class 2 and BCS Class 4 poorly water-soluble drugs.

How do I make FeSSIF?

FeSSIF dissolution medium is prepared in less than a couple of minutes with 3F Powder and diluted FeSSIF Buffer Concentrate.

For more product details download the FeSSIF Technical Data Sheet (TDS) here

Download our Biorelevant Dissolution Guides here.