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PLGA Nanoparticles Formed by Single- or Double-emulsion with Vitamin E-TPGS
Published on: December 27, 2013
PLGA microdevices for retinoids sustained release produced by supercritical emulsion extraction: continuous versus
Giovanna Della Porta1, Roberta Campardelli, Nunzia Falco
1Dipartimento di Ingegneria Industriale, Università di Salerno, Via Ponte don Melillo, 84084 Fisciano (SA), Italy; Laboratorio di Ingegneria Cellulare e Molecolare (DEIS), Università di Bologna, Via Venezia 52, 47521 Cesena (FC), Italy. gdellaporta@unisa.it.
Journal of Pharmaceutical Sciences
|June 4, 2011
Summary
Supercritical emulsion extraction (SEE) with carbon dioxide efficiently produced poly(lactic-co-glycolic)acid microspheres for retinyl acetate encapsulation. This method yielded superior microsphere quality and controlled drug release compared to conventional techniques.
Area of Science:
- Materials Science
- Chemical Engineering
- Pharmaceutical Technology
Background:
- Poly(lactic-co-glycolic)acid (PLGA) microspheres are widely used for drug delivery.
- Efficient encapsulation and controlled release of active compounds remain a challenge.
- Supercritical fluid technology offers potential for improved microencapsulation processes.
Purpose of the Study:
- To investigate the use of supercritical emulsion extraction (SEE) for encapsulating retinyl acetate (RA) into PLGA microspheres.
- To compare the characteristics of microspheres produced by SEE with those from conventional liquid-liquid extraction.
- To evaluate the performance of batch and continuous SEE systems for microsphere production.
Main Methods:
- Preparation of oil-in-water emulsions containing retinyl acetate and PLGA in acetone with an aqueous glycerol phase.
- Processing of emulsions using supercritical carbon dioxide (SC-CO2) for oily phase extraction and microsphere formation.
- Comparison of microsphere characteristics (morphology, aggregation) obtained via SEE and conventional methods.
- Evaluation of continuous SEE (SEE-C) using a packed tower in countercurrent mode.
Main Results:
- SEE produced spherical, free-flowing PLGA/RA microspheres, unlike aggregated ones from conventional extraction.
- Continuous SEE (SEE-C) demonstrated higher recovery and process efficiencies.
- PLGA/RA microspheres produced via SEE-C (80 bar, 36°C) had sizes of 3.3–4.5 μm with 80%–90% encapsulation efficiency.
- Drug release was dependent on initial drug loading, with higher loading leading to slower release over 6 days.
Conclusions:
- Supercritical emulsion extraction is an effective method for producing high-quality PLGA microspheres with excellent retinyl acetate encapsulation.
- Continuous SEE offers advantages in efficiency and microsphere recovery.
- The study provides insights into controlling drug release profiles by adjusting initial drug loading.
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