Synthesis and Properties of a Cationic Gemini Surfactant with the Hydrophenanthrene Structure

A novel cationic gemini surfactant with the hydrophenanthrene structure has been synthesized from dehydroabietylamine. Its structure was confirmed by IR, H-1 NMR, and elemental analysis. The critical micelle concentration (CMC) of the surfactant and its surface tension at the CMC (gamma (CMC)) in aqueous solution were about 1.58 x 10(-5) mol L-1 and 36.6 mN m(-1) at 25 A degrees C, respectively. The emulsion composed of equal amounts of benzene and an aqueous solution with 0.1 % gemini surfactant as emulsifier maintained its stability for 8.5 h. Meanwhile, the antimicrobial activities of the gemini surfactant against Pseudomonas aeruginosa, Escherichia aerogenes, and Staphylococcus epidermidis were much better than those of bromogeramine and ampicillin sodium against the same bacteria, and its minimum inhibitory concentrations (MIC) were 16, 32, and 4 mu g mL(-1), respectively.