NMR and confocal microscopy studies of the mechanisms of burst drug release from PLGA microspheres

Accelerated in vitro release testing of implantable PLGA microsphere/PVA hydrogel composite coatings

“…The initial burst release decreased with increasing inherent viscosity of the PLGA polymers (approximately 57 %, 48 %, 39 % and 30 % in 24 h for DLG2A, 503H, DLG3A and DLG4A, respectively). PLGA polymers with low inherent viscosities have better hydration and swelling properties, thus resulting in faster diffusion of surface-associated drug into the release medium (Messaritaki et al, 2005). It was noted that dexamethasone release mechanisms appeared different among these formulations.…”

The Influence of Surfactant on PLGA Microsphere Glass Transition and Water Sorption: Remodeling the Surface Morphology to Attenuate the Burst Release

“…The process of drug release from polyester microspheres is an area of intense study and draws on data from erosion models (49,50) and studies of the burst release and drug dispersal within a matrix (51). In this case, the primary emulsion was found to be best stabilized with Triton X-100 yielding the highest encapsulation efficiencies for the FIII9 0 -10 (20).…”

Cytotoxicity of Paclitaxel in Biodegradable Self-Assembled Core-Shell Poly(Lactide-Co-Glycolide Ethylene Oxide Fumarate) Nanoparticles

“…This indicated that most (if not all) of the PLAF and PLGF NPs degraded after 15 and 28 days, respectively, by hydrolytic degradation and erosion of the matrix. These results demonstrate that there is a mechanistic difference between the release characteristics of PLAF and PLGF NPs and those of high molecular weight (commercially available) PLA and PLGA (43)(44)(45)(46). Release of active agents from high molecular weight PLA and PLGA systems is by diffusion through a porous matrix while release from PLAF and PLGF NPs, due to low macromer molecular weight and high density of hydrophilic chain ends, is by hydrolytic degradation and erosion of the matrix (47).…”