Synthesis and antibacterial activity of immobilized quaternary ammonium salts

Quaternary ammonium salts were immobilized on hydrophilic gels based on sucrose methacrylates (SM) and tested for their antibacterial properties. The cross-linked polymers were prepared by copolymerization of monomer–SM mixtures with 4-vinylpyridine and subsequent quaternization with 1-bromoctane and 1-bromoctadecan and by esterification of SM gels with 3-pyridine carboxylic acid chloride and quaternization. In addition, immobilized quaternary salts bonded by hydrophobic as well as by hydrophilic spacers were synthesized by esterification of SM gels with 11-bromundecanoic acid chloride and the tetraethylene glycol-based acid chloride 13c, respectively, and subsequent reaction of the halogen-substituted gels with tertiary amines. Suspension tests for antibacterial properties of the immobilized bactericides against Escherichia coli, Staphylococcus aureus, and Micrococcus luteus demonstrated high activity of the quaternary salts bonded by the hydrophobic spacer. Advantageously, these insoluble bactericides can be applicated without contamination of the substrate; they can be removed easily and used repeatedly. © 1994 John Wiley & Sons, Inc.