Air humidity solubility assay
10.16438/j.0513-4870.2016-0289
- VernacularTitle:空气湿度溶解度测定法
- Author:
Yu HUANG
1
;
Xian-cheng ZHAN
1
;
Fang-jun LÜ
1
Author Information
1. Key Laboratory of Drug Targeting and Drug Delivery Systems, Ministry of Education, West China School of Pharmacy, Sichuan University, Chengdu, 610041, China
- Publication Type:ORIGINAL ARTICLES
- Keywords:
solubility;
equilibrium method;
kinetic method;
air humidity solubility assay;
gravimetry;
electrolyte NRTL model
- From:
Acta Pharmaceutica Sinica
2016;51(9):1472-1475
- CountryChina
- Language:Chinese
-
Abstract:
Measurement of drug solubility is one of the key elements of compound characterization during the drug discovery and development process. A broad variety of solubility assay methods have been developed, including equilibrium method which requires analysis of the equilibrium composition and kinetic method which monitors the concentration of a compound dynamically at the time when a precipitate first appears or disappears in the solution. Despite the numerous experimental methods, precise drug solubility values are hard to obtain for time-consuming, sample size and manual work. In this article, we reported a new method, namely air humidity solubility assay, which measures the relative humidity of the air in equilibrium with the solution at a given temperature, and then calculates solubility from the relative humidity according to extended-non random two liquid (NRTL) model. NaCl was used as a model drug, and the solubility was measured at the temperature of 20-50℃. The results indicate that the solubility of NaCl determined with the new method is generally comparable to that determined by gravimetry that is reported in literature. The new method has a relative error of less than 2%. Although the accuracy is lower than that of gravimetry, air humidity solubility assay is more convenient, practical, operational and universal. This method provides a supplement to the existing methods.
