Study on the preparation and drug release of p H-dependent plant microcapsules in vitro

In order to study the new plant based enteric-coated microcapsules and realize the digestive tract drug delivery, the microcapsules were prepared by acetate starch, pectin and carrageenan and performed to investigate their characteristics and drug release process and safety. A kind of p H-dependent plant microcapsules was prepared by pectin, acetate starch and carrageenan.The microcapsules were characterized by Fourier transform infrared spectroscopy, dissolution property, scanning electron microscopy and cytotoxicity test, and the drug release behavior of microcapsules was further studied.The results showed that there was no dissolution or drug release in different p H conditions when the microcapsules contain no pectin. The microcapsule containing one percent of pectin had the strongest release capacity under neutral partial acidity conditions. The drug release rate of microcapsules decreased with the increase of pectin concentration. There almost no drug release when the microcapsules contained three percent of pectin. The results of cytotoxicity showed that the microcapsules were safe and nontoxic. Pectin is a key component of p H-dependent microcapsules, which can be used for the effective release of microcapsules in pH neutral environment by regulating the pectin content, to achieve drug release in the intestinal tract and improve the bioavailability of drugs.