Question
Posted on: February 5 2023How can I exactly calculate the amount of necessary additive?
When making capsules, determining the amount of excipient is often arbitrary and not very precise. We visually look at the volume of powder it occupies in a bell jar or measuring cylinder. After that it is still difficult to mix geometrically.
Answer
When determining the amount of excipient for certain capsule sizes, one can proceed fairly simply on the basis of the tapped density of the powder. The tapped density of a powder is always the same (but can vary per lot) in contrast to the bulk density.
The tapped density of a product is stated on the packaging for some raw material ranges (such as FSA and Magis Pharm). If your raw material supplier does not provide this information, you can use a cheap device such as a Densitometer .
The calculation is done simply by:
- volume necessary of the capsules
- volume the asset occupies (by mass divided by doing the tapped density)
- Multiply residual volume by the tapped density of the excipient.
To simplify this calculation you can use this excel .