Elucidating the Interaction Interplay Between the Gabapentin an Anticonvulsant Drug and 2-Hydroxyethylammonium Octanoate-Based Surface-Active Ionic Liquids

Gabapentin, as an anticonvulsant drug with its low-permeability feature in the gastrointestinal region, is one of the commonly prescribed medications for the treatment of epilepsy. Recently surface-active ionic liquids (SAILs) have been utilized to resolve this issue in aqueous solutions. Understanding the thermophysical and micellization behavior of SAILs is of paramount importance as it enables the design of efficient SAILs, and allows for drug property enhancement in pharmaceutical formulations. This study explores the thermophysical and micellization behavior of SAILs (2-hydroxyethyl)ammonium octanoate [2-HEA][Oc], bis(2-hydroxyethyl)ammonium octanoate [bis-HEA][Oc], tris(2-hydroxyethyl)ammonium octanoate [tris-2-HEA][Oc] in varied aqueous gabapentin solutions through the utilization of electrical conductivity, surface tension measurement, and conductor like screening model (COSMO) analysis. The electrical conductivity measurement for aqueous SAILs were conducted at temperature range of 298.15 K to 318.15 K and for the SAILs in aqueous gabapentin solution at varying concentration of 0.0100 to 0.0500 mol kg⁻¹ were conducted at 298.15 K. The surface tension measurements were conducted for the aqueous SAILs and SAILs in aqueous gabapentin solution with varying concentration at 298.15 K. The both of the techniques were employed to evaluate the critical micelle concentration (CMC) and its related thermophysical properties. For better understanding the interactions between these components, COSMO was utilized. The study revealed that CMC values increased with temperature but decreased with increasing gabapentin concentration. Thermodynamic parameters of micellization were calculated through electrical conductivity and surface tension measurement. Finally, interactions between SAILs and gabapentin were investigated through limiting molar conductivity \(\Lambda_{0}\) ${\mathrm{\Lambda }}_0$ , and association constant \(K_{A}\) $K_A$ , determination.