Abstract
1) Attempt was made to suppress the hydrolysis of acetylsalicylic acid with anionic (sodium laurylsulfate), cationic (cetylethyldimethylammonium bromide and benzalkonium chloride), and nonionic (Emulgen 120) surfactants. The hydrolysis of the undissociated form of acetylsalicylic acid is suppressed by the three kinds of surfactants and that of the anionic form is suppressed by cetylethyldimethylammonium bromide and benzalkonium chloride. 2) Through the ultraviolet spectra and the partition coefficient, it was ascertained that the undissociated form of acetylsalicylic acid is solubilized with the above three kinds of surfactants and the anionic form interacts with only a cationic surfactant.
