Study on the Properties of Mixed Micelles of Disodium Salt of 3-({2-[(2-Carboxy-ethyl)-dodecanoyl-amino]-ethyl}-dodecanoyl-amino)-propionic Acid in Solution Systems

Abstract

This study focuses on the properties of mixed micelles of di-sodium salt of 3-({2-[(2-Carboxy-ethyl)-dodecanoyl-amino]-ethyl}-dodecanoyl-amino)-propionic acid (symbolized as DLMC) in solution systems (DLMC/DTAB and DLMC/AEO₆). The micro-polarity of the mixed micelles was determined by the fluorospectrophotometer. When the concentration is above CMC, the micellar micro-polarity and the aggregation number (N_m) of the mixed micelles were measured by a steady state fluorescence quenching method. The average hydrodynamic radius (R_h) of the mixed micelles was studied by means of dynamic light scattering. The results show that the micro-polarity of micelle nucleus decreases obviously with increasing concentration. The aggregation number of DLMC mixed systems is smaller than that of single surfactants. The difference of the proportion of the two surfactants has little effect on the aggregation number of mixed systems. It is easy to generate molecular aggregates with lower curvature from DLMC than the corresponding monomeric surfactant (DTAB), and DLMC can generate huge linear micelles at low concentrations when mixed with other surfactants.