Facile fabrication of pH-responsive and swellable slow release microparticles of chlorpheniramine maleate with chitosan-starch matrices and their crosslinks.

We synthesized chitosan and modified same by blending with starch, crosslinking the matrices with sodium tripolyphosphate (TPP) and encapsulation with the drug chlorpheniramine maleate (CPM). These microparticles were characterized by FTIR, TGA, and SEM techniques. The amounts of CPM released from the microparticles generally decreased for the TPP-crosslinked beads but increased as the starch composition increased. Their release rates were best described by zero-order kinetics while their release mechanisms followed less-Fickian diffusional release. Our findings show that both the uncrosslinked and crosslinked chitosan-starch beads are promising carriers for the slow release of CPM. [ABSTRACT FROM AUTHOR]