Indexed on: 15 Jun '17Published on: 14 Jun '17Published in: Journal of Chemical & Engineering Data
The inverse gas chromatography study on the fluconazole drug surface was performed, and the net retention volumes, polar probes, and VN of n-alkanes are determined at four temperatures over the range 318.15–333.15 K. The net retention values of n-alkanes were used to evaluate the London dispersive surface free energy γSL by three different methods, namely, the Donnet–Park, Dorris–Gray, and Schultz methods. The γSL values were found to increase from 318.15 to 323.15 K for all three methods and then decrease from 323.15 to 333.15 K. The γSL values were found to be slightly higher in the Schultz method when compared to the results of the Donnet–Park and Dorris–Gray methods. The specific free energy values ΔGaS and the specific enthalpy ΔHaS values have been calculated using the VN data of polar probes. The Guttmann Lewis acid–base parameters, Ka and Kb, were obtained using ΔHaS values and were found to be 0.217 and 1.518, respectively. The surface character (Kb/Ka) was found to be 7.0. The results revealed that the fluconazole powder surface contains relatively more basic sites than acidic sites and can combine strongly with acidic substrates. The surface energy and acid–base data of fluconazole can be used during formulation of the drug and to understand the drug release process.