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Preparation and Characterization of Individual and Multi-drug Loaded Physically Entrapped Polymeric Micelles
Published on: August 28, 2015
Preparation of sustained release microparticles with improved initial release property
Goo-Young Jung1, Young-Eun Na, Mork-Soon Park
1College of Pharmacy, Chungnam National University, Daejeon, 305-764, Korea.
Archives of Pharmacal Research
|April 24, 2009
Summary
Poly(D,L-lactide-co-glycolide) (PLGA) microparticles blended with d-alpha-tocopheryl polyethylene glycol 1000 succinate (TPGS) significantly reduce initial peptide burst release. The PLGA+10.0% TPGS formulation demonstrated optimal sustained peptide delivery.
Area of Science:
- Biomaterials Science
- Drug Delivery Systems
- Polymer Chemistry
Background:
- Achieving sustained peptide release from injectable microparticles is crucial for effective therapeutic delivery.
- Poly(D,L-lactide-co-glycolide) (PLGA) microparticles are a common platform, but often exhibit burst release and lag phases.
- d-alpha-tocopheryl polyethylene glycol 1000 succinate (TPGS) is explored as a potential excipient to modify release profiles.
Purpose of the Study:
- To investigate the impact of incorporating TPGS into PLGA microparticles on the in vitro release kinetics of an encapsulated peptide.
- To evaluate different TPGS concentrations for optimizing sustained peptide release.
- To understand the formulation-dependent factors influencing peptide release from PLGA-TPGS microparticles.
Main Methods:
- Microparticles were prepared using the solvent evaporation method.
- Peptide-loaded PLGA microparticles were formulated with varying percentages of TPGS (0%, 5.0%, 10.0%).
- In vitro drug release studies were conducted in phosphate buffer (pH 7.0) to assess release profiles over time.
Main Results:
- Unmodified PLGA microparticles showed significant initial burst release (22.3% in 1 day) and a lag phase.
- Incorporation of TPGS markedly reduced initial burst release, with 5.0% TPGS showing 8.6% and 10.0% TPGS showing 5.5% release in 1 day.
- PLGA+10.0% TPGS composite microparticles exhibited a triphasic release pattern with minimal initial burst, improved encapsulation, larger particle size, and fewer pores, indicating desirable sustained release.
Conclusions:
- TPGS incorporation effectively mitigates initial burst release and lag phase in PLGA peptide microparticles.
- The PLGA+10.0% TPGS formulation provides the most favorable sustained release profile among the tested formulations.
- TPGS acts as a beneficial additive, enhancing peptide encapsulation and modifying microparticle characteristics for controlled drug delivery.
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