Application of PLGA-ion exchange resin microcapsules of sulfasalazine for embolization therapy

Objective This work involves preparation and evaluation (in vitro/in vivo) of microcapsules containing sulfasalazine-ion exchange resin complex (resinate) to induce emboli for treatment of solid cancer. Methods The drug-resin complex (resinate) had been optimized by using drug:resin ratio (1:8), by suspending the resin in sulfasalazine aqueous solution with at 400 rpm for 120 min at 50 degrees C. For controlling the release of drug, microencapsulation for the resinate was applied where 21 formulas with different resinate:poly(lactic-co-glycolic acid) ratios 2:1, 1:1 and 1:2 were prepared by solvent evaporation method to study the effect of different variables including resinate:polymer ratio, stirring speed, effect of temperature and aqueous phase volume on microencapsulation efficiency and percent of yield. Results The in vitro release study for the prepared resinate, which had 72% entrapment efficiency, showed 80.992% of drug released within 15 min and the release continued until 99.83% within 75 min formula was found to be F19 had 76.70% encapsulation efficiency and 89.40% yield. The in vitro release study for selected formula showed that 32% of drug released within 1 h and 78% of drug released within 20 days and the release continued up to 96% within 45 days indicating a controlled release manner with spherical microcapsule of 595 mu m. The preliminary in vivo work using rabbits showed instant occlusion of the central auricular artery of the rabbit ear leading to ischemia within 3 days that continued to the end of study period. Conclusion This work show the suitability of microcapsules size to prevent blood flow and forming embolization with controlling release of the drug that may treat the solid tumor.