Yonezawa Y, Shirakura K, Otsuka A, Sunada H
Faculty of Pharmacy, Meijo University, Nagoya, Japan.
Chem Pharm Bull (Tokyo). 1991 Mar;39(3):769-72. doi: 10.1248/cpb.39.769.
An equation for dissolution from the whole surface of a nondisintegrating single component tablet under the sink condition was derived. Also, equations for several dissolution manners of the tablet under the sink condition were derived in the postulation of the dominant dissolution rate constant which determines the dissolution manner. The applicability or validity of these equations were examined by the dissolution measurements with nondisintegrating single component tablets. About one-tenth the amount of the amount needed to saturate the solution was used to prepare a tablet, and dissolution measurements were carried out with the tablet whose flat or side surface was masked with an adhesive tape in accordance with the conditions for derivation of equations. Among the derived equations, dissolution from the whole surface of a tablet was expressed by a form similar to the cube root law equation for particles. Hence, a single component tablet compressed by the use of a suitable amount was thought to behave like a single crystal. Also, equations derived for several dissolution manners were thought to be applicable for the dissolution of a nonspherical particle and crystal concerning the crystal's habit and its dissolution property, and the extended applicability was examined by converting the crystal into a simplified or idealized form, i.e., rectangle or plate.
推导了在漏槽条件下非崩解型单组分片剂整个表面的溶出方程。此外，在假定决定溶出方式的主导溶出速率常数的情况下，推导了片剂在漏槽条件下几种溶出方式的方程。通过对非崩解型单组分片剂进行溶出度测定，考察了这些方程的适用性或有效性。制备片剂时使用的药物量约为使溶液饱和所需量的十分之一，并根据方程推导条件，用胶带覆盖片剂的平面或侧面进行溶出度测定。在推导的方程中，片剂整个表面的溶出可用类似于颗粒立方根定律方程的形式表示。因此，认为使用适量药物压制而成的单组分片剂的行为类似于单晶。此外，针对几种溶出方式推导的方程被认为适用于非球形颗粒和晶体的溶出，涉及晶体习性及其溶出特性，并通过将晶体转化为简化或理想化形式（即矩形或平板）来考察其扩展适用性。
