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Coherent anti-Stokes Raman Scattering (CARS) Microscopy Visualizes Pharmaceutical Tablets During Dissolution
Published on: July 4, 2014
Excipient interaction with cetylpyridinium chloride activity in tablet based lozenges
R M Richards1, J Z Xing, K M Mackay
1School of Pharmacy, Robert Gordon University, Schoolhill, Aberdeen, United Kingdom.
Pharmaceutical Research
|August 1, 1996
Summary
Tablet excipients, particularly magnesium stearate, significantly reduce the antimicrobial activity of cetylpyridinium chloride (CPC) in lozenges. To maintain CPC efficacy, limit magnesium stearate to 0.3% w/w in tablet formulations.
Area of Science:
- Pharmaceutical Sciences
- Microbiology
Background:
- Cetylpyridinium chloride (CPC) is an antiseptic agent used in oral hygiene products.
- Tablet excipients can potentially affect the stability and efficacy of active pharmaceutical ingredients.
Purpose of the Study:
- To investigate the impact of tablet excipients on the antimicrobial activity of cetylpyridinium chloride (CPC).
- To determine the interaction between specific excipients and CPC.
Main Methods:
- Developed an analytical assay to assess CPC-excipient interactions.
- Conducted in vivo studies with human volunteers to measure oropharyngeal microbial reduction.
- Performed in vitro antimicrobial activity tests against Staphylococcus aureus, Streptococcus pyogenes, and Candida albicans, evaluating excipient and pH effects.
Main Results:
- Tablet-based lozenges showed significantly reduced antimicrobial activity compared to candy-based lozenges or aqueous CPC solutions.
- Magnesium stearate was found to adsorb CPC, leading to a substantial decrease in antimicrobial activity at concentrations of 0.4% lozenge weight and higher.
Conclusions:
- Reduced CPC activity in tablet lozenges is attributed to its adsorption by magnesium stearate, decreasing its availability in solution.
- For tablet lozenges containing CPC at 250 µg/ml, magnesium stearate content should not exceed 0.3% w/w to prevent significant reduction in antimicrobial efficacy.
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