Synthesis and Characterization of a New Gemini Surfactant Derived from 3a,7a,12a-trihydroxy-5ß-cholan-24-amine (Steroid Residue) and Ethylenediamintetraacetic Acid (Spacer)

Abstract

A new gemini steroid surfactant derived from 3a,7a,12a-trihydroxy-5ß-cholan-24-amine (steroid residue) and ethylenediamintetraacetic acid (spacer) was synthesized and characterized in aqueous solution by surface tension measurements and fluorescence intensity of pyrene. These techniques evidence the existence of a threshold concentration, cac, below which a three layers film is formed at the air-water interface. At high concentrations, the intensity ratio of the vibronic peaks of pyrene, I1/I3, (= 0.81) is very close to published values for sodium cholate micelles, indicating that the probe is located in a region with a very low polarity and far from water