ORAL CONTROLLED RELEASE AND TASTE MASKED SUSPENSION OF CEPHALEXIN USING ION EXCHANGE RESIN

Ion exchange resins are versatile drug carriers capable of different functions like taste masking and controlled drug release. Objective of the study was to use ion exchange resins for masking the taste of Cephalexin and to provide controlled release in the form of reconstitutable suspension. Cephalexin is first generation antibiotic with bitter taste and short half-life. Polymer-coated resinates were evaluated for percent drug release and taste masking and compared with microparticles of plain drug coated with polymers. The coating process was optimized by 32 factorial design using polymer concentration and pump speed as independent variables and percent drug release as dependent variable. Optimized batch was used to prepare the suspension which was evaluated for drug leaching, sedimentation, dispersibility and percent release. Tulsion A-23 was showed maximum drug binding (83.23%) and maximum Cephalexin loading was (83.16%). The percent complexation at 1:1 drug: resin ratio was found to be 83.68%. Percent drug release of Cephalexin suspension, coated microparticles and uncoated resin was found to be 99.16% in 12 h, 90% drug in 8 h and 96% within 5 h respectively. Coating with retarding polymers gave an extended release up to 12 h. Increase in pump speed and polymer concentration led to decrease in percent release. Leaching of coated drug resin complex suspension and microparticle was observed to be 0.5 % and 2.1% respectively. Negligible leaching was observed in coated drug resin complex suspension hence it was concluded that Tulsion A-23 resinate complex reduces the bitterness as well as taste masking of cephalexin successfully. We may conclude that this technology can be explored for other similar drugs for taste masking purpose.