If you work with soft capsules in the pharmaceutical industry, then you’ll know that cross-linking can occur in certain temperature and humidity conditions, especially with reactive and aggressive fillings. The gelatin can unintentionally form a rigid barrier that prevents the active ingredient within the capsule from reaching its destination at the right time (or at all). If this happens soft capsules become increasingly less soluble over time, resulting in overly long dissolution times in the GI tract and slow release properties.
Despite the overwhelming advantages of gelatin capsules, this is a knock-out criterion. Even if a pharmaceutical manufacturer can guarantee optimal storage conditions, one unpredictable variable in the equation remains: the end consumers and how they handle the capsules. Reactive ingredients are particularly difficult: substances with reactive groups (e. g. aldehyde function) may lead to cross-linking. Also, multiple charged cations or anions in the filling may form ionic bounds that can cause dissolution issues. A tough cookie for capsule manufacturers!
Various attempts by the pharmaceutical industry to reduce cross-linking with additives have only been partially successful. Pharma experts at GELITA, however, have taken a different path: they’ve established a new production process that controls the molecular weight distribution of gelatin and therefore minimizes soft capsule dissolution problems.
This solution can be described as a sort of “self-defense mechanism,” brought about by a combination of large and small molecules. These molecules react with the gelatin and prevent both intra- and inter-molecule cross-linking reactions within the fill formulation. Available as RXL® Prime, this technological breakthrough adds extra value to gelatin capsules, significantly reduces the amount of cross-linking and enhances the dissolution properties of the capsules.
To guarantee long-term capsule stability for critical fills, RXL® Advanced has been developed, the next generation of reduced cross-linking technology. It provides reduced pellicle formation, which, in turn, minimizes the cross-linking potential and supports controlled fill release performance throughout the entire shelf-life — even for critical fills.
So, no matter what the end consumer does or what kind of reactive ingredient you may have, RXL® Prime is designed to optimize capsule release performance and enable you to provide the best possible product.
Have questions or want to declare war on cross-linking in your capsules? Contact us today.
