Preparation and characterization of microspheres for controlled release of anti HIV drug.

A series of blend microspheres were developed from gelatin and hydroxypropyl cellulose (HPC) by emulsion crosslinking method employing glutaraldehyde (GA) as a crosslinker. Valganociclovir hydrochloride (VHCL), an anti HIV drug, was loaded in to these microspheres via insitu method. These microspheres were characterized by Fourier transform infrared spectroscopy (FTIR), to confirm the formation of crosslinking and absence of chemical interactions between drug, polymer and crosslinking agent. Further the microspheres were characterized by scanning electron microscopy to study the surface morphology of the microspheres and observed that the microspheres have smooth surface with spherical structure and no phase separation. The microspheres with the average particle sizes ranging from 614.5μm to 693.4μm were obtained. X-ray diffraction (X-RD) studies were performed to understand the crystalline nature of drug and its uniform distribution into blend microspheres. An in vitro release study was performed in phosphate buffer solution (pH-7.4) at 370C. The release rates were fitted to an emperical equation to understand the diffusion parameters, which indicate non-Fickian or anomalous trend release of VHCL. Further the results indicated that the release of drug was found for more than 12 h.

Synthesis and characterization of Interpenetrating polymer network microspheres of acryl amide grafted Carboxymethylcellulose and Sodium alginate for controlled release of Triprolidine hydrochloride monohydrate.

Interpenetrating polymer network [IPN] microspheres of acrylamide (AAm) grafted on Carboxymethyl cellulose (CMC) and Sodium alginate (NaAlg) microspheres were prepared by water-in-oil (W/O) emulsion method. These microspheres were loaded with Triprolidine hydrochloride monohydrate (TPH) and cross-linked with glutaraldehyde. The prepared microspheres were characterized by Differential scanning calorimetry (DSC), Scanning electron microscopy (SEM) and Laser particle size analyzer. DSC thermo grams of TPH loaded AAmg- CMC/NaAlg IPN microspheres confirmed the molecular level distribution in the polymer matrix. SEM of the microspheres suggested the formation of spherical particles. Swelling experiments on the microspheres provided important information on drug diffusion properties. Release data have been analyzed using an empirical equation to understand the nature of transport of drug containing solution through the polymeric matrices. The controlled release characteristic of the matrices for TPH was investigated in pH 7.4 media. Particle size and size distribution of the microspheres was studied by laser light diffraction particle size analyzer. Drug was released in a controlled manner upto 12 h.