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PubMed · 12880701

Structure formation in injectable poly(lactide-co-glycolide) depots.

Liwei Wang·Lothar Kleiner·Subbu Venkatraman
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Abstract

Solutions of low-molecular-weight poly(lactide-co-glycolide) (PLGA) in organic solvents have been investigated as novel injectable drug depots for drug delivery over periods of weeks to months. In this paper, we investigated the structure formation in a PLGA/benzyl benzoate system, using controlled stress rheometry, gel permeation chromatography (GPC), and differential scanning calorimetry (DSC). GPC analysis demonstrated a decrease in molecular weight as a function of time and temperature, indicating degradation. Rheological experiments showed that the flow properties of PLGA/benzyl benzoate solutions were affected by a combination of degradation and gelation; the latter was also detected by an endotherm in DSC and by three-dimensional structure formation studies by rheology. Extent of degradation and gelation of PLGA were shown to depend on the solvent.

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BenzoatesCalorimetry, Differential ScanningChemistry, PharmaceuticalChromatography, GelDelayed-Action PreparationsDrug CarriersDrug CompoundingDrug StabilityDrug StorageInjectionsLactic AcidMetoclopramidePolyglycolic AcidPolylactic Acid-Polyglycolic Acid CopolymerPolymersPyrrolidinonesRheologySolventsStructure-Activity RelationshipTemperatureTime FactorsComparative StudyJournal ArticleResearch Support, Non-U.S. Gov't

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Liwei Wang, Lothar Kleiner, Subbu Venkatraman. 2003-07-31. Structure formation in injectable poly(lactide-co-glycolide) depots.. https://doi.org/10.1016/s0168-3659(03)00198-6

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