A modification of synthesis of amino acid ionic liquids (AAILs) based on 1-alkyl-3-methylimidazolium cation and L-Serinate anion [Cnmim][Ser] (n = 8, 10, 12) was developed. The structures of the AAILs based on serinate were confirmed by 1H NMR and 13C NMR spectroscopies. The electrical conductivity in aqueous mixtures of ionic liquids from the family 1-alkyl-3-methylimidazolium serinate [Cnmim][Ser] (n = 8, 10, 12) at 298.15 K were measured. The results of the electrical conductivity study clearly show that the general features of micellar aggregation of relatively long-chain imidazolium IL are analogous to those in the case of traditional surfactants. Critical micelle concentrations (cmc) of AAILs, degree of counterion binding ( β ), standard Gibbs energy of micellization (Δ G °m) for them were estimated from the experimental data. The dependences of the cmc, β and Δ G °m, on the length of the alkyl chain of the cations were discussed. These compounds were initially screened for biology activity by a simple zone of inhibition study against Staphylococcus aureus ATCC 5638 (gram-positive bacteria), Escherichia coli ATCC 25922 (gram-negative bacteria) and Candida albicans ATCC 885653 (fungus). The data obtained have shown that among AAILS the [C10mim][Ser] is more effective against this bacteria.
amino acid ionic liquid, 1-alkyl-3-methylimidazolium cation, electrical conductivity, micellization, antibacterial effect
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