Effect of KCl on Volumetric Properties of Aqueous Solutions of Guaifenesin Drug

In pharmacology, treatment, prevention and diagnosis a disease or promotion of health make by a chemicals called a pharmaceutical drug or medicine. Guaifenesin drug (GG) is used to control cough and is sometimes combined with dextromethorphan, an antitussive (cough medicine)[1]. The bioavailability and stability of a drug can be affected from the interactions with different chemicals[2]. Therefore, in this work, density data of GG drug in water and aqueous solutions of KCl have been measured within KCl molality range of (0.05, 0.1, and 0.15) mol kg-1 at T = (298.15, 308.15 and 318.15) K.The apparent molar volume have been calculated from density values with equation of in which m is molality of solution, M is the molar mass of the GG drug, d and d0 are densities of solution and solvent, respectively. The behaviours of apparent molar volume for aqueous solution of GG and also GG + KCl indicates a decrease in the interaction of GG-H2O, as well as GG-KCl-H2O with temperature increasing.The values for the aqueous solutions containing drug and also KCl are higher than those of the aqueous solutions containing the drug and increase with increasing the concentration of salt. This behavior suggests that the size of the GG molecule increases due to the decrease in the interaction of GG with water in the presence of salt. The apparent molar volume values of the considered solutions have successfully been modelled via the Redlich–Meyer type equation[3] in the dilute region.