Preparation, characterization and in vitro activities evaluation of curcumin based microspheres for azathioprine oral delivery

The main target of this study was the preparation, characterization and in vitro activities evaluation ofmicrospheres curcumin-based able to incorporate azathioprine, useful for psoriasis treatment. Curcuminwas derivatized with acryloyl chloride in order to introduce polymerizable groups in its structure. Theobtained polymerizable drug was characterized by Fourier transform infrared (FT-IR), to confirm esterlinkages, and by 1HNMR, to establish the functionalization degree. The ability of curcumin derivativeto inhibit cell proliferation, in human breast cancer cells, gave an IC50 value for viability of 20 lM. Acrylatedcurcumin also showed a strong antioxidant activity against lipid peroxidation induced in rat livermicrosomal membranes. Then, spherical microparticles, based on curcumin derivative, were preparedby suspension radical copolymerization. The obtained microparticles were characterized by FT-IR spectroscopy,dimensional and morphological analysis. Particle size investigation revealed a mean diameterof around 5.8 lm. Microspheres showed a very good swelling behavior in simulating intestinal fluids.Their azathioprine loading efficiency, determined by spectophotometric analysis was equal to 80%.Release profile of azathioprine showed an initial dot of around 60% and a further release for 24 h.