A method using biodegradable polylactides/polyethylene glycol for drug release with reduced initial burst.

Y Y Huang; T W Chung; T W Tzeng

doi:10.1016/s0378-5173(99)00060-5

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A method using biodegradable polylactides/polyethylene glycol for drug release with reduced initial burst.

Y Y Huang·T W Chung·T W Tzeng

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Abstract

Post-coating of biodegradable polylactides (PLA)/polyethylene glycol (PEG) microspheres with a gelatin film produced by dipping the microspheres into a gelatin solution to reduce the initial drug release burst was investigated. Biodegradable block PLA/PEG microspheres, prepared by w/o emulsion/solvent evaporation, showed that the hydrophilic segment PEG protruded to the sphere surface. However, these microspheres also showed a large burst release in the initial period. Post-coating of the PLA/PEG microspheres with a gelatin film by dipping the microspheres into a dilute gelatin solution effectively inhibited the initial burst release rate in the drug release tests. Post-coating of gelatin reduced 98% of the burst release. With thicker coatings, there were slower releasing rates, and the release rate can be simply related to the coating thickness.

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Anti-Arrhythmia Agents Biocompatible Materials Biodegradation, Environmental Coated Materials, Biocompatible Delayed-Action Preparations Drug Carriers Gelatin Lactates Lidocaine Microspheres Polyethylene Glycols Propranolol Journal Article Research Support, Non-U.S. Gov't

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Y Y Huang, T W Chung, T W Tzeng. 1999-05-10. A method using biodegradable polylactides/polyethylene glycol for drug release with reduced initial burst.. https://doi.org/10.1016/s0378-5173(99)00060-5

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