Synthesis, surface properties and bioactivity of novel 4-Substituted 1,2,3-Triazole quaternary ammonium surfactants

Abstract Series of novel 1,2,3-triazole based quaternary ammonium surfactants with different hydrophobic chain length and head group substituents were synthetized and characterized. Their surface properties and aggregation behavior were discussed on the basis of tensiometry and conductimetry measurements by using several parameters, including critical micelle concentration (CMC), surface tension at the cmc (γcmc), adsorption efficiency (pC20), effectiveness of surface tension reduction (Πcmc), minimum surface area occupied by a molecule (Amin) at the air − water interface and standard Gibbs free energy of micellization Δ G Mic 0 . These heterocyclic surfactants exhibit much lower CMC values as compared with those reported for conventional alkyltriethyl ammoniums and alkylbenzyldiethyl ammonium salts. Their micelles formation and surface adsorption in aqueous media can be tuned out through a suitable choice of the substituent attached to the polar head. Triethyl ammonium (CnTzTEA] and diethylbenzyl ammonium surfactants (CnTzBz) showed improved micellization behavior than tetradecyl diethyl ammonium (CnTzC14) homologous. The in vitro antimicrobial activity of the surfactants against B. subtilis, P. aerugenosa and A.niger strains was also investigated. CnTzBz series possessing benzyl chain showed better activity against all the tested microorganisms with minimum inhibitory concentration ranging from 6 to 57 μmol/L.