Diclofenac sodium loaded gelatin magnetic microspheres for intra-arterial administration: formulation, characterization and in vitro release studies.

Abstract

Gelatin magnetic microspheres loaded with diclofenac sodium were prepared by emulsification and crosslinking by glutaraldehyde. The microspheres were formulated with 23-30% theoretical diclofenac sodium and magnetite content. The formulated microspheres were characterized by drug loading, entrapment efficiency, encapsulation efficiency, magnetite content, FT-IR spectroscopy, particle size analysis, optical microscopy, scanning electron microscopy, and in vitro release studies. The data obtained from the in vitro release studies were applied to various kinetic models. The FT-IR revealed no drug/polymer interaction. The average particle size was between 36 to 61 microm depending on quantity of magnetite and gelatin used. Optical microscopy and SEM showed spherical and compact nature of microspheres. The formulated microspheres released the drug for a period of 42 to 78 hours depending on drug loading. The release was diffusion controlled at lower drug loading and dissolution/diffusion controlled at higher drug loading.