Effect Of Structural Relaxation On The Preparation And Drug Release Behavior Of Poly(lactic-co-glycolic)acid Microparticle Drug Delivery Systems
| Autor: | S. Dean Allison |
|---|---|
| Rok vydání: | 2008 |
| Předmět: |
Materials science
Chemistry Pharmaceutical Drug Compounding Pharmaceutical Science Dosage form Diffusion chemistry.chemical_compound Differential scanning calorimetry Polylactic Acid-Polyglycolic Acid Copolymer Technology Pharmaceutical Organic chemistry Lactic Acid Particle Size Microparticle chemistry.chemical_classification Drug Carriers Molecular Structure Polymer Glycolates Kinetics PLGA Models Chemical Pharmaceutical Preparations Solubility chemistry Chemical engineering Drug delivery Particle size Drug carrier Polyglycolic Acid |
| Zdroj: | Journal of Pharmaceutical Sciences. 97:2022-2035 |
| ISSN: | 0022-3549 |
| DOI: | 10.1002/jps.21124 |
| Popis: | Control of burst release is a major challenge in the development of poly(lactide-co-glycolide) (PLGA) microparticle drug delivery systems. It has been well-documented in previous literature that formulation and processing variables determine particle morphology, which in turn, governs drug diffusivity and burst release. However, it is not generally appreciated that PLGA polymers used for microparticle systems are typically amorphous, and as such, undergo structural relaxation during processing and storage, characterized by enthalpy and volume reduction. Volume reduction due to structural relaxation can decrease drug diffusivity within microparticles and affect burst release. The magnitude of the driving force leading to structural relaxation is linked to the rate of particle hardening, and is affected by process parameters. Studies that directly address structural relaxation in PLGA microparticles indicate that the manufacturing process and residual solvent levels, as well as the nature of the interaction between drug and polymer affect the rate of structural relaxation. Therefore, the conditions chosen for particle fabrication may be a major source of variability in the burst release and may affect the stability of the drug release profile during storage. The potential effects of structural relaxation on drug release are likely to be formulation specific. Additional work is required to understand and control the relationship between microparticle processing, structural relaxation, and performance of PLGA microparticle drug delivery systems. |
| Databáze: | OpenAIRE |
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