Effect of the Hydrophobic Tail of a Chiral Surfactant on the Chirality of Aggregates and on the Formation of Wormlike Micelles

Author(s)

Creatto, Eduardo J. ^[1] ; Ceccacci, Francesca ^[2] ; Mancini, Giovanna ^[3] ; Sabadini, Edvaldo ^[1]

Affiliation

^[1] Univ Estadual Campinas, Inst Chem, Dept Phys Chem, POB 6154, BR-13084862 Campinas, SP - Brazil

^[2] Univ Roma Sapienza, Dipartimento Chim, Sez Meccanismi Reaz, CNR, Ist Metodol Chim, Ple A Moro 5, I-00185 Rome - Italy

^[3] CNR, Ist Metodol Chim, Via Salaria Km 29-300, I-00016 Rome - Italy

• Document type: Journal article
• Source: Langmuir; v. 34, n. 44, p. 13288-13295, NOV 6 2018.
• Web of Science Citations: 2

Abstract

The micellization of chiral enantiopure surfactants, dodecyl-N,N-dimethyl-N-(S)-(1-phenyl) ethylammonium bromide and hexadecyl-N,N-dimethyl-N-(S)-(1-phenyl) ethylammonium bromide, was investigated by circular dichroism spectroscopy and isothermal titration calorimetry. The formation of wormlike micelles (WLMs) upon the addition of sodium salicylate to the aqueous solutions of the surfactant was observed only in the case of hexadecyl-N,N- dimethyl-N-(S) -(1-phenyl) ethylammonium bromide. The presence of WLMs was assessed by cryogenic transmission electron microscopy, rheology, and isothermal titration calorimetry experiments, and their supramolecular chirality was investigated by circular dichroism spectroscopy. Depending on the length of the hydrophobic tail, molecular chirality is transferred into a different chiral supramolecular trait. Our findings demonstrate that hydrophobic interactions by controlling the organization and functions of self-assemblies also control the transcription of the chiral information from molecules to complex supramolecular systems. (AU)

• FAPESP's process: 15/25406-5 - Organizing matter: colloids formed by association of surfactants, polymers and nanoparticles
• Grantee: Watson Loh
• Support Opportunities: Research Projects - Thematic Grants