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PLGA Nanoparticles Formed by Single- or Double-emulsion with Vitamin E-TPGS
Published on: December 27, 2013
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In vitro release testing methods for vitamin E nanoemulsions.
Jacqueline M Morais1, Diane J Burgess1
1Department of Pharmaceutical Sciences, School of Pharmacy, University of Connecticut, 69 North Eagleville Road, Storrs, CT 06269, USA.
International Journal of Pharmaceutics
|September 3, 2014
Summary
This study investigated vitamin E acetate release from nanoemulsions. Diffusion across the interfacial film limited release, resulting in sustained vitamin E delivery from these formulations.
Area of Science:
- Pharmaceutical Sciences
- Drug Delivery Systems
- Nanotechnology
Background:
- Vitamin E acetate is poorly water-soluble, posing challenges for formulation.
- Nanoemulsions offer potential for improving solubility and delivery of lipophilic drugs.
- Understanding drug release mechanisms is crucial for optimizing nanoemulsion-based therapies.
Purpose of the Study:
- To characterize the in vitro release properties of vitamin E acetate from oil/water nanoemulsions.
- To evaluate different in vitro release testing methods for nanoemulsions.
- To identify the rate-limiting step governing drug release.
Main Methods:
- Oil/water nanoemulsions formulated with canola oil, CremophorRH40, and Span80 using the emulsification preparation (EPI) process.
- In vitro drug release assessed using dialysis sac, reverse dialysis sac, and USP Apparatus 4 methods.
- Macro- and microscopic stability evaluations performed.
Main Results:
- Nanoemulsions exhibited good macro- and microscopic stability.
- Reverse dialysis sac and USP Apparatus 4 were suitable for release testing; dialysis sac method showed slower release due to violated sink conditions.
- Diffusion across the interfacial film was identified as the rate-limiting step for vitamin E acetate release.
- Sustained/prolonged release of vitamin E was observed, attributed to its high partition coefficient and nanoemulsion interfacial film properties.
Conclusions:
- The EPI process effectively produced stable vitamin E acetate nanoemulsions.
- Diffusion across the interfacial film is the primary mechanism controlling in vitro release.
- Nanoemulsions demonstrate potential for sustained delivery of poorly water-soluble drugs like vitamin E acetate.
Keywords:
Canola oil/water nanoemulsionsDialysis adapterDialysis sac and reverse dialysis sacIn vitro release testing methodsUSP apparatus 4Vitamin E acetateMore Related Videos
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