Interaction of Mixed Surfactants with Bacterial Lipopolysaccharide.

The interaction of lipopolysaccharide isolated from Klebsiella O3 strain with cationic and cationic-nonionic mixed surfactants has been studied by turbidimetry and by spectrophotometric, spectrofluorometric, viscosity, and conductance measurements. The cationic surfactants benzyldimethyl-n-hexadecylammonium chloride (BDHAC), cetyltrimethylammonium bromide (CTAB), cetylpyridinium chloride (CpCl), dodecylpyridinium chloride (DpCl), and nonionic surfactants polyoxyethylene glycol-tert-octylphenyl ether (Triton X-100), polyoxyethylenesorbitan monolaurate (Tween-20), and polyoxyethylene (23) lauryl ether (Brij-35) were used in all the experiments as single surfactants and also as mixed surfactants of different compositions. Mixed surfactants were found to be more effective in binding with the lipopolysaccharide molecules. Micellar effects of cationic and cationic-nonionic mixed surfactants on binding with the anionic polymer are presented in this paper. The binding was found to be electrostatic in origin and also hydrophobic in nature to a certain extent. Copyright 1998 Academic Press.