对于大多数口服控释制剂而言,溶出是药物释放的主速过程。它们与一般制剂不同,吸收速率常慢于消除速率,因之药物在体内从片剂、包衣颗粒或骨架等的溶出和释放,成为关键的主速过程,体外模拟较为困难。由于控释制剂要通过一系列不同pH的环境(从pH接近1的胃到pH7的小肠远端),在制剂的设计和研究中,pH是必须考虑的主 Dissolution is the major rate of drug release for most oral controlled release formulations. They differ from the usual formulations in that the rate of absorption is often slower than the rate of elimination, and the dissolution and release of the drug from the tablets, coated granules or scaffolds, etc., become the key, dominant rate process in vivo and are more difficult to model in vitro. Since controlled release formulations pass through a range of different pH environments (from the stomach near pH 1 to the distal small intestine at pH 7), pH is a major consideration in formulation design and research