Xylan microparticles for controlled release of mesalamine: Production and physicochemical characterization.

Xylan extracted from corn cobs was used to produce mesalamine-loaded xylan microparticles (XMP5-ASA) by cross-linking polymerization using a non-hazardous cross-linking agent. The microparticles were characterized by thermal analysis (DSC/TG), X-ray diffraction (XRD), Infrared spectroscopy (FTIR-ATR) and scanning electron microscopy (SEM). A comparative study of the in vitro drug release from XMP5-ASA and from gastro-resistant capsules filled with XMP5-ASA (XMPCAP5-ASA) or 5-ASA was also performed. NMR, FTIR-ATR, XRD and DSC/TG studies indicated molecularly dispersed drug in the microparticles with increment on drug stability. The release studies showed that XMPCAP5-ASA allowed more efficient drug retention in the simulated gastric fluid and a prolonged drug release lasting up to 24 h. XMPCAP5-ASA retained approximately 48 % of its drug content after 6 h on the drug release assay. Thus, the encapsulation of 5-ASA into xylan microparticles together with gastro-resistant capsules allowed a better release control of the drug during different simulated gastrointestinal medium.

Development of diethylcarbamazine-loaded poly(caprolactone) nanoparticles for anti-inflammatory purpose: Preparation and characterization

Abstract Diethylcarbamazine-loaded nanoparticles were previously evaluated for their anti-inflammatory activity. However, little is known regarding their physicochemical properties. Thus, the purpose of this study was to physiochemically characterize diethylcarbamazine-loaded poly(caprolactone) nanoparticles and evaluate their in vitro cytotoxicity. All formulations were prepared using the double-emulsion method. The average particle size was in the ranged between 298 and 364 nm and the polydispersity indexes were below 0.3. The zeta potential values were marginally negative, which may be related to drug loading, as higher loading led to an increase in the modulus of the zeta potential values. Fourier transform infrared spectroscopy (FT-IR) and X-ray powder diffraction (XRD) analysis did not reveal any chemical interactions between the chemicals used and the absence of drug in crystalline form on the nanoparticle surfaces. The in vitro drug release study revealed a concentration-dependent release from the nanoparticles into the medium. The in vitro cytotoxicity assay demonstrated the biocompatibility of the blank and loaded nanoparticles. Hence, all formulations presented good physicochemical and safety properties, corroborating the in vivo anti-inflammatory activity, previously reported by our group.