The interplay of phase inversion and membrane formation in the initial burst release of an in situ forming for vancomycin delivery system
Paper ID : 1191-MST2015-FULL
mina Darestani-Farahani1, Ebrahim Vasheghani-Farahani1, Hamid Mobedi *2, fariba ganji1
1tarbiat modares university
2Tehran, Pajoohesh Blvd
A main problem in drug delivery is the design of a suitable platform for controlled drug release. The delivery system should have a drug loading capacity sufficient to supply the required dosage over the wanted release period and ideally should exhibit little or no bursting with zero-order release kinetics. In this respect, controlled drug delivery based on polymer solution platforms has gained widespread attention in recent years, finding applications as injectable and implantable systems.Such systems usually contain a solution of a polymer, solvent, and in some cases additives, in which the active pharmaceutical Ingredient (API) is suspended or dissolved.
The morphology of the resulting membrane plays an important role in the release kinetics. Thus, successful design of a membrane-based drug delivery system involves understanding and controlling the interplay of phase inversion, morphology development, and the resulting drug distribution in the solidified membrane structure . The purpose of this study is investigation of a membrane-base in situ- forming formulation for vancomycin delivering in one month period.A series of solvents (PEG400, DMSO, NMP and acetone ) were used in preparation of implants.
The role of solvent properties on the phase inversion dynamics and in vitro vancomycin release
kinetics of polylactic-co-glycolic acid (PLGA) solutions has been examined using in vitro release studies. The resulted morphology of surface and cross section of implants was also investigated by SEM.
Comparing drug release and morphological structure of devices shoed that Vancomycin release from the DMSO or NMP-based system is primarily governed by the dynamics of phase inversion and exhibits a distinct burst region followed by a much slower release. Alternatively, depots with low solvent /water affinity(PLGA in Acetone or PEG400) undergo much slower phase inversion, resulting in a less porous, more fluid, two-phase structure that also releases vancomycin more uniformly.
vancomycin, in situ- forming,phase inversion,initial burst release
Status : Paper Accepted (Oral Presentation)