Preparation of magnetic microspheres of mesalamine by phase separation emulsion polymerisation technique

The study involved magnetic microspheres of mesalamine prepared by phase separation emulsion polymerization (PSEP) method technique. Magnetic microspheres were prepared by PSEP method to target them to the colon. Three polymers namely Eudragit S 100, ethylcellulose and chitosan were used for the preparation of magnetic microspheres. Magnetite content and entrapment of mesalamine was evaluated. Eudragit S 100, ethylcellulose and chitosan were used as polymers. Fourier transform infrared spectroscopy (FTIR) spectrum of drug and polymer was taken to visualize the compatibility of drug and polymer. Scanning electron microscope (SEM) images show the uniformity and particle size of the microspheres formed. The in vitro release study was carried out in phosphate buffer pH 6.8. The various results obtained were fit into the mathematical models and the Higuchi model was found to be most suitable for the formulations. Chitosan magnetic microspheres prepared by phase separation emulsion polymerization were found to be best in all the evaluation parameters (practical yield, magnetite content, magnetic responsivity of microspheres, particle size, in vitro release studies). They contain maximum magnetite content which is the utmost feature for the magnetic microspheres. Microspheres can be targeted by the external magnetic field applied due to magnetite entrapped. Thus toxicity and reticuloendothelial clearance can be minimized. Key words: Chitosan, Eudragit S 100, ethylcellulose, magnetic, phase separation emulsion polymerization (PSEP).