Influence of Temperature and Additives (Glucose/Urea) on the Antidiabetic Drug-Mediated Micellization of CTAB

Abstract

Comprehending the interactions between drugs and surfactants is critically significant for enhancing drug delivery processes and formulating effective drug compositions. This research aims to elucidate the temperature-induced aggregation of cetyltrimethylammonium bromide (CTAB) in combination with metformin hydrochloride (MHC); in addition to emphasizing the influence of glucose and urea on micellization. The conductivity measurements were employed to probe the interactions in the CTAB-MHC system containing aqueous glucose/urea throughout a spectrum of ambient temperatures. The addition of MHC facilitated micellization by lowering the CMC values of CTAB compared to those of CTAB in pure water. Glucose, by establishing hydrogen bonds with water, renders the solvent less conducive for the hydrophobic tails of the CTAB surfactant, thereby elevating the CMC. Urea diminishes the hydrophobic action that promotes micellization by altering the water structure, hence increasing the CMC. A U-shaped pattern has been noticed in the correlation between temperature and the CMC of CTAB-MHC in both aqueous and aqueous glucose/urea environments. Thermodynamic parameters (entropy of micellization,〖∆S〗_m^0; enthalpy of micellization,〖∆H〗_m^0; and Gibbs free energy of micellization,〖∆G〗_m^0) and physicochemical variables (CMC and counterion dissociation, α) have been used to characterize the interaction between CTAB and MHC. The negative 〖∆G〗_m^0 values reveal that the CTAB-MHC mixture undergoes spontaneous micellization in both pure water and aqueous glucose/urea environments. Negative〖∆S〗_m^0 and〖∆H〗_m^0values indicate the predominance of H-bonding, while positive values of 〖∆S〗_m^0 and〖∆H〗_m^0 indicate hydrophobic interactions. The negative 〖∆H〗_m^0 values could potentially be caused by London dispersion forces. The research enhances comprehension of how additives (glucose/urea) influence the aggregation of surfactant molecules in the presence of pharmaceuticals.