Micellization Behavior of a Cationic Gemini Surfactant, Pentanediyl-1,5-Bis(Dimethylcetylammonium Bromide): Effect of Asparagine and Temperature

Herein, we report the effect of amino acid and temperature on the micellization of a cationic gemini surfactant, pentanediyl-1,5-bis(dimethylcetylammonium bromide), 16-5-16. In aqueous solution, the critical micelle concentration (CMC) of 16-5-16 was measured by the conductivity method at different fixed temperatures and a fixed concentration of asparagine. An increasing trend of CMC values was found with both higher (asparagine) concentrations (i.e., increases with increasing asparagine concentration) and higher temperatures (i.e., increases with increasing temperature). The thermodynamics (viz. standard Gibbs energy (Delta G(m)(0)), standard enthalpy (Delta H-m(0)), and standard entropy (Delta S-m(0))) of micellization of the gemini surfactant (16-5-16) were evaluated, which indicated less stability of the 16-5-16 solution in the presence of amino acid (asparagine).