Synthesis, Surface and Antimicrobial Activities of Novel Cationic Gemini Surfactants

A series of novel cationic gemini surfactants [C n H2n+1–O–CH2–CH(OH)–CH2–N+(CH3)2–(CH2)2]2·2Br− [3a (n = 12), 3b (n = 14) and 3c (n = 16)] having a 2-hydroxy-1,3-oxypropylene group [–CH2–CH(OH)–CH2–O–] in the hydrophobic chain have been synthesized and characterized. Their water solubility, surface activity, foaming properties, and antibacterial activity have been examined. The critical micelle concentration (CMC) values of the novel cationic gemini surfactants are one to two orders of magnitude smaller than those of the corresponding monomeric surfactants. Furthermore, the novel cationic gemini surfactants have better water solubility and surface activity than the comparable [C n H2n+1–N+(CH3)2–(CH2)2]2·2Br− (n-4-n) geminis. The novel cationic gemini surfactants 3a and 3b also exhibit good foaming properties and show good antibacterial and antifungal activities.