Bi W, Choi D, Row K. Adsorption Equilibrium of Caffeine and Theophylline on C18 Column Using Ionic Liquids as Additives. ajc [Internet]. 2010 Mar. 30 [cited 2024 Jun. 30];22(5):4003-9. Available from: https://asianpubs.org/index.php/ajchem/article/view/11640