| Abstract
| - Chirality of the amphiphile to promote gelation in the given solvent medium is narrated in a new catanionicsurfactant mixture from a twin-chiral, twin-tailed surfactant derived from tartaric acid and cetyltrimethylammonium bromide (CTAB). The surfactant bis(decyloxy) succinic acid (BDSA), a chiral Gemini-type surfactantwith a rigid spacer, in association with CTAB formed pH and temperature responsive vesicles and hydrogels.Molecular chirality gave rise to supertwisted fibrillar hydrogels at a BDSA:CTAB molar ratio of 1:2 and in31% water content. The hydrogels from enantiomeric BDSA were reversibly pH and irreversibly temperatureresponsive at pH <6.2 and at 55 °C, respectively, whereas the corresponding sodium succinates formedtransparent clear gels reversible to both pH and temperature. The hydrogels were able to entrap and releasemodel dye molecules, Rhodamine B, and Congo red, responding to thermal and pH stimuli. Circular dichroismunraveled the chiro-optical behavior of the assembled fibers, allowing monitoring of aggregation and packing.The presence and the relative configuration of the stereogenic centers in the structure of this low molecularweight gelator have been observed to be critical to form gels. The high curvature Gaussian gel network wasmodeled based on the chiral elastic membrane approach and the pitch angle of the Gaussian twist was estimatedto be 45°.
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