Preparation and evaluation of magnetic microspheres of mesalamine (5-aminosalicylic acid) for colon drug delivery

ObjectiveTo study magnetic microspheres of mesalamine (5-aminosalicylic acid) for colon drug delivery.MethodsMagnetic microspheres were prepared by solvent evaporation technique for use in the application of magnetic carrier technology. An attempt was made to target mesalamine (5-aminosalicylic acid) to its site of action i.e. to colon. Eudragit S-100, ethylcellulose and chitosan were used in three different drug: polymer ratios i.e. 1:1, 1:2 and 1:3. The microspheres were characterized in terms of particle size, percentage yield, drug content, encapsulation efficiency, in vitro release pattern and ex vivo study. The microspheres were uniform in size and shape. The in vitro release profile was studied in pH 7.4 phosphate buffer medium using USP dissolution apparatus.ResultsChitosan microspheres were found to be better retained in terms of percentage release of the drug. Thus chitosan microspheres could be better retained at their target site.ConclusionFlow characteristics are also better in case of chitosan magnetic microspheres. Thus reticuloendothelial clearance can be minimized and site specificity can be increased