Characterization of tetradecyltrimethylammonium bromide (TTAB) microemulsion by microemulsion electrokinetic chromatography

Abstract

The aim of this work is to characterize a tetradecytrimethylammonium bromide (surfactant), heptane (oil) and butan-1-ol (co-surfactant) microemulsion by microemulsion electrokinetic chromatography (MEEKC) through the solvation parameter model. This model is especially useful to describe the distribution of neutral solutes between two phases (the aqueous phase and the microemulsion). To do that, 69 neutral compounds with representative enough properties were analysed. The solvation parameter model is based on the linear free energy relationships (LFERs), which can be written as: log k = c + eE + sS + aA + bB + vV (3) where k is the MEEKC retention factor and E, S, A, B and V are the Abraham solute descriptors. The coefficients of the system (e, s, a, b and v) can be obtained by multiple linear regression and provide the properties of the studied microemulsion system. Once the coefficients of the system are determined, the studied system can be compared with other systems with known coefficients. In this work, the TTAB MEEKC system was correlated with octanol-water partition and SDS MEEKC systems. The coefficients are similar enough, thus the TTAB MEEKC system can be used to emulate the octanol-water partition. The octanol-water partition emulation is especially useful as it is a measure of the lipophilicity of compounds, which plays an important role in drug discovery and development