Rapid Indomethacin Release from Porous Pectin Particles as a Colon-Targeted Drug Delivery System

The conventional pectin delivery systems in the colon are often impaired by a slow release rate. Nanostructured particles, especially porous ones, have gained popularity as drug delivery systems owing to their high mass transfer efficiency. In this research, porous pectin particles were synthesized as drug carriers (using indomethacin as a model drug) via template-assisted spray drying. Specific surface areas of the porous pectin particles have been improved by up to 203 m² g^-1 compared with nonporous particles (1 m² g^-1). The porous structure shortened the diffusion path and improved the release rate of drug molecules. Additionally, the predominant drug release mechanism from porous pectin particles is Fickian diffusion, which is different from the combination of erosion and diffusion mechanism observed for nonporous particles. As a result, these porous drug-loaded pectin particles demonstrated rapid drug release rates of up to three times faster than nonporous particles. Control of the release rate could be achieved by changing the porous structure of the particles. This strategy is an efficient means to synthesize porous particles allowing rapid drug release into the colonic target.