A suppository-base-matrix tablet for time-dependent colon-specific delivery system

Our research has focused on the main design features and release performances of time-dependent colon-specific (TDCS) delivery tablets, which relies on the relative constancy that is observed in the small intestinal transit time of dosage forms. But inflammatory bowel disease（IBD）can affect the transit time, and usually results in watery stool. Compared to the TDCS and wax-matrix TDCS tablet, a promising time-dependent colon-specific delivery system was investigated. In our study, a suppository-base-matrix coated tablet was evaluated. Water soluble suppository-base helps the expansion of tablet, facilitates uniform film dissolution and achives high osmotic pressure. Combining the expansion of carboxymethyl starch sodium (CMS-Na) and the moisture absorption of NaCl, the coated TDCS tablet obtained a burst and targeted drug delivery system. A very good correlation between in vitro drug release and in vivo outcome was observed. This TDCS coated tablet provides a promising strategy to control drug release to the desired lower gastrointestinal region.

本研究聚焦于时间依赖型结肠定位（time-dependent colon-specific, TDCS）给药片的核心设计特征与释药性能，该类制剂依托制剂在小肠内转运时间相对恒定的特性。但炎症性肠病（inflammatory bowel disease, IBD）会干扰肠道转运时间，且通常会引发水样便。相较于传统TDCS片剂与蜡质骨架型TDCS片剂，本研究对一种更具应用前景的时间依赖型结肠定位给药系统展开了研究。本研究对一种栓基质骨架包衣片进行了评价：水溶性栓基质可促进片剂膨胀，助力包衣膜均匀溶出，并可实现较高的渗透压。通过结合羧甲基淀粉钠（carboxymethyl starch sodium, CMS-Na）的膨胀特性与氯化钠（NaCl）的吸湿性能，该包衣型TDCS片剂构建出了具有突释效应与靶向性的给药系统。研究观察到该制剂的体外释药行为与体内药效表现之间存在极佳的相关性。该包衣型TDCS片剂为实现药物在目标下消化道区域的可控释药提供了一种极具潜力的解决方案。