Physical gelation of organic liquids by achiral amino acid based amphiphilic gelators: Effect of chirality

We report gelation behavior of a series of N-acyl-β-alanine (Cn-β-Ala) gelators in a variety of organic liquids. The effect of alkyl chain length was studied to elucidate gelation mechanism. The gelation behavior of the Cn-β-Ala gelators was compared with that of corresponding N-acyl-l-alanine (Cn-l-Ala) derivatives. Unlike Cn-l-Ala the Cn-β-Ala gelators failed to gel aliphatic hydrocarbons and exhibit phase-selective gelation in the presence of water. The gelation ability of Cn-β-Ala was observed to be poorer than Cn-l-Ala gelators. Also Cn-β-Ala organogels are thermally less stable, but they are observed to have higher mechanical strength than Cn-l-Ala organogels.