Aggregation behaviours and bactericidal activities of novel cationic surfactants functionalized with amides and ether groups

A series of novel cationic surfactants, N-alkylcaramoylmethyl-N-[2-(2-phenoxyacetamido)-ethyl]-N,N-dimethylammonium chloride, were synthesized and their chemical structures were characterized using 1H-NMR, 13C-NMR, ESI-MS and FT-IR. Their aggregation behaviours in aqueous solution were systematically investigated by surface tension and electrical conductivity methods. It was found that the surfactants have higher surface activity compared with a similar structural surfactant. A series of thermodynamic parameters of aggregation indicate that the aggregation is entropy-driven at the investigated temperatures. In addition, they possess excellent bactericidal activities against the selected strains.