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Solubility of Hydrophobic Compounds in Aqueous Solution Using Combinations of Self-assembling Peptide and Amino Acid
Published on: September 20, 2017
Relationship between critical relative humidity and solubility of drugs
Yingli Wang1, Xiancheng Zhan, Lin Luo
1Key Laboratory of Drug Targeting, West China School of Pharmacy, Sichuan University, Chengdu, Sichuan, P. R. China.
Abstract:
Both the critical relative humidity (H(cr)) and the solubility are important physicochemical properties that affect the quality of drugs. However, the relationship between them is not noticed yet. By an analysis of interaction between molecules of drug and water, the conclusion logically obtained is: the higher the solubility is, the lower the H(cr) will be. To validate this idea, the H(cr) and the solubility of 33 drugs and chemicals were determined and a negative linear correlation was found between the two factors when the solubility was expressed as the mole fraction of water. This negative linear correlation was further confirmed by a computer simulation according to modified Debye-Hückel equation.
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