• Makes the second version of FeSSIF (Fed State Simulated Intestinal Fluid)
  • Contains physiological surface active ingredients
✔ In Stock For Immediate Dispatch
Product Code
Powder Weight
Shelf Life 18 Months
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  • Safety Data Sheet
  • Certificate of Analysis
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What is FeSSIF-V2?

It’s a ‘biorelevant’ dissolution medium that simulates human gut fluid after eating food:

  • FeSSIF: Fasted State Simulated Intestinal Fluid

Testing your product in Biorelevant Media can help predict what will happen when it enters the gastro-intestinal tract. This is because the media are physiologically discriminating: they contain biological surfactants (sodium taurocholate and lecithin) that can have a big impact on drug solubility. Conventional buffers and surfactants (such as sodium lauryl sulfate) do not replicate the complex environment of the GI tract anywhere near as accurately.

As well as the bile salts and lecithin present in the original FeSSIF, version two contains digestive components (sodium oleate and glycerol monooleate) which make it more physiologically relevant than its predecessor.

Why do I need it?

Testing in physiologically relevant media can help determine:
Biorelevant solubility: how much drug dissolves in the Biorelevant Medium
Estimated cost: $2.80 (based on 2 glass vials of 5ml FeSSIF-V2 made from V2FES01)

Biorelevant dissolution: how much time drug takes to dissolve in the Biorelevant Medium
Estimated cost: $180 (based on 6 dissolution vessels of 500ml FeSSIF-V2 made from V2FES03)

These in vitro tests can significantly reduce the amount of costly in vivo experiments needed because they can help you identify promising drug candidates and distinguish good formulations from bad ones.

How do I make it?

Very easily!

Reproducible results

We use the highest grade of ingredients and analyze their purity before manufacture. The powders are made in our factory in London where we carefully control every aspect of their production. They are only released after rigorous analysis by a GMP certified laboratory in Germany. All products are supplied with a Certificate of Analysis. These steps ensure you will get highly reproducible results from our products every time you use them.


We have used it frequently in our lab for more than a year because this ‘ready-to-use’ FeSSIF-V2 can be easily reproduced even for small volumes (i.e. for solubility purposes) compared with the conventional prepared media which require multiple ingredients to be sourced and use up a lot of analytical time. Of course, we are pleased to use FeSSIF-V2 powder for simulating fed conditions since it makes our ‘lab job’ so much easier! Thank you for existing!

Alexandra Papathanasiou, Analytical Dev Manager, Greece


We have found the FeSSIF V2 powder to be easy to use and dependable. Your online instructions for making buffers are straightforward and easy to understand. We will no doubt keep using your products in future research.

Princeton University, USA


Trying to convince people that we should use biorelevant media in order to accurately predict the in vivo situation is one thing, but knowing that these media are also easy to make should convince everybody to work with it. Even in fed state media (where we are dealing with a complex intraluminal environment), biorelevant.com has now launched the new FeSSIF-V2 which can lead to more optimized predictions in postprandial conditions.

Bart Hens, KU Leuven, Belgium


The products are perfect... we are very pleased with them and the service offered.

Jessica Engelschmidt, Losan Pharma Gmbh, Germany


I've always gotten reliable and reproducible data with the products that helped the formulations department better adjust their experiments to produce desired dissolution profiles. Love the wide range of media as well!

Theravance Biopharma, USA