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Updated: Jul 3, 2026
04:41
Measuring Lactase Enzymatic Activity in the Teaching Lab
Published on: August 6, 2018
Lactose contaminant as steroid degradation enhancer
Florentine Nieuwmeyer1, Kees van der Voort Maarschalk, Herman Vromans
1Department of Pharmaceutics, Schering Plough Corporation, P.O. Box 20, 5340 BH, Oss, The Netherlands. fjsnieuwmeyer@yahoo.com
Pharmaceutical Research
|August 2, 2008
Summary
Steroid degradation is influenced by lactose particle size and contaminants. Smaller lactose particles and the presence of lactose-phosphate significantly increase steroid degradation, impacting pharmaceutical stability.
Area of Science:
- Pharmaceutical Sciences
- Solid-State Chemistry
- Drug Stability
Background:
- Pharmaceutical processes involving solid excipients can accelerate drug degradation.
- Understanding excipient-drug interactions is crucial for maintaining drug stability.
Purpose of the Study:
- To investigate critical factors affecting the stability of a steroid in the presence of lactose.
- To determine the impact of lactose particle size and composition on steroid degradation.
Main Methods:
- A steroid was mixed or wet granulated with lactose of varying particle sizes.
- Analysis of steroid degradation under different conditions and in the presence of lactose contaminants.
Main Results:
- Smaller lactose particles and increased surface area led to higher steroid degradation rates.
- Lactose-phosphate, an intrinsic contaminant, significantly enhanced steroid degradation.
- Granule composition, particularly the presence of small primary lactose particles within larger granules, correlated with increased degradation.
Conclusions:
- Lactose contaminant levels and granule composition are key determinants of steroid stability in pharmaceutical formulations.
- Particle size engineering of excipients like lactose requires careful consideration of potential degradation pathways.
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