Preparation, characterization and in vitro drug release properties of polytrimethylene carbonate/polyadipic anhydride blend microspheres

Abstract

Polyadipic anhydride (PAA), an aliphatic polyanhydride, and polytrimethylene carbonate (PTMC), an aliphatic polycarbonate, were synthesized via ring opening polymerization of oxepan-2,7-dione and melt-condensation of trimethylene carbonate (1,3 dioxan-2-one), respectively. PTMC-PAA blend microspheres containing different ratios of buprenorphine HCl (2, 5, and 10%) were prepared by an oil-in-oil emulsion solvent removal method. Microspheres with different ratios of PTMC-PAA (85/15, 70/30, and 55/ 45) containing 5% buprenorphine HCl were prepared. Microspheres were spherical with visible cracks and pores on the surface. The average particle size of microspheres was around 200 m for all microspheres. Drug loading efficiency of PTMC-PAA microspheres (85/15, 70/30, and 55/45) was 97.2, 95.2, and 70.2%, respectively. With the increase in the PTMC ratio, the melting point and the enthalpy of melting were both decreased. The mechanism for drug release from PTMC-PAA blend microspheres were generally a combination of drug diffusion through polymers and biodegradation of the polymers. In first three days, the release from microspheres followed zero order kinetics and was dependent on the PAA content. After three days the drug release from microspheres followed first order kinetics. In conclusion it was demonstrated that buprenorphine HCl release from microspheres could be successfully controlled by using different ratios of PTMC-PAA blends.

Improved drug loading and antibacterial activity of minocycline-loaded PLGA nanoparticles prepared by solid/oil/water ion pairing method

“…[1][2][3][4][5] PLGA is one of the most biocompatible and biodegradable polymers, and it has been widely studied for preparing drug-loaded nanoparticles. 6,7 Several methods, such as phase separation or coacervation, emulsification diffusion, spray-drying, and emulsion-solvent evaporation techniques have been used to prepare PLGA nanoparticles.…”

Comparison of micelles formed by amphiphilic poly(ethylene glycol)‐b‐poly(trimethylene carbonate) star block copolymers

“…Poly(ethylene glycol) (PEG) has nontoxicity and has been found to possess biocompatibility demanded when introducing synthetic materials into biomedical applications 13. Poly(trimethylene carbonate) (PTMC) is an attractive material for biomedical application, such as drug delivery carrier, tissue engineering, surgical sutures, and etc., because of its good biodegradability and biocompatibility 14–16. Recently, considerable effort has been devoted to creating biodegradable PEG‐ b ‐PTMC block copolymers 17, 18.…”