In solid preparation stability studies, "moisture competition" between contents and pharmaceutical excipients is often the core factor leading to product failure. Especially for herbal powders, antibiotics, probiotics, and premium supplements, selecting HPMC (hypromellose) capsules is a professional solution to address product stability from the fundamental level.
1. The "Limitations" of Gelatin Capsules in Low-Moisture Environments
Traditional empty gelatin capsules contain approximately 13% - 16% moisture. When filling highly hygroscopic materials (such as herbal powders, antibiotics, probiotics), the contents will absorb moisture from the capsule shell, leading to:
Brittleness Phenomenon: The capsule shell becomes brittle due to loss of moisture balance. Even in blister packaging with desiccants, it can easily break during storage or transportation.
Activity/Disintegration Impairment: For live bacterial preparations like probiotics, moisture transfer directly affects bacterial survival rates; while certain aldehyde-containing ingredients can cross-link with gelatin, causing the capsule shell to form an insoluble film, severely affecting disintegration performance. For a detailed comparison of this material difference, see our material analysis article.
2. Technical Advantages of Empty HPMC Capsules
As a new generation of plant-derived pharmaceutical excipients, HPMC capsules demonstrate stronger adaptability in physical and chemical properties:
1. Extremely Low Moisture Content and Mechanical Toughness
HPMC capsule moisture content is typically stable between 3% - 8%. Its mechanical toughness does not depend on moisture. Even in extremely dry environments, the capsule shell can still maintain good flexibility, effectively preventing brittleness. This makes it the ideal carrier for highly hygroscopic materials and moisture-sensitive preparations.
2. Chemical Inertness, Eliminating Cross-Linking
HPMC has extremely strong chemical stability, contains no amino acids, and does not react with contents. This means it has excellent excipient compatibility, ensuring the preparation maintains stable disintegration performance throughout its shelf life.
3. Strong Environmental Adaptability
For easily oxidizable ingredients, HPMC capsules can provide superior barrier protection and are less sensitive to storage temperature and humidity, helping maintain product batch stability.
3. CDE Association Review and Global Access Support
For pharmaceutical companies with higher compliance requirements, HPMC capsules are not only a performance choice, but also part of the project documentation review:
CDE Association Review Support: Plant capsules produced by StellarCaps are registered with the National Medical Products Administration (NMPA) and can efficiently cooperate with pharmaceutical companies to complete related product declarations and audits. For our quality assurance system, visit our Quality Assurance page to learn more.
Biological Safety: Non-animal derived properties, effectively avoiding BSE/TSE risks, aligning with global clean label trends and mainstream pharmaceutical access standards.
4. Supply Assurance and Professional Collaboration
StellarCaps is committed to providing robust supply chain support and high-standard pharmaceutical excipients for major customers:
Machine Performance: Our HPMC capsules have excellent dimensional consistency on fully automatic high-speed filling machines, ensuring precise filling weight and stable machine yield.
Supply Planning: For commonly used industry specifications, we can discuss order planning and batch supply arrangements according to the confirmed product plan. To learn about specification selection, see our Complete Guide to Empty Capsule Specification Selection.
Conclusion
If you are facing issues with product discoloration, brittleness, or disintegration failure after moisture absorption, welcome to contact us to discuss targeted solution suggestions together.