Disinfection of water with quaternary ammonium salts insolubilized on a porous glass surface.

Insoluble quaternary ammonium salts bound to porous glass showed antibacterial activity. An agent designated as G(12), which had a dodecyl alkyl chain, was selected for some antibacterial tests on comparison of it with the agent reported previously. The antibacterial activity of G(12) toward Escherichia coli was mainly due to the adsorption of cells and therefore gradually decreased during continuous treatment of a cell suspension. The lost G(12) activity was completely recovered by washing with ethanol, and the activity of refreshed G(12) decreased in the same manner as that of fresh G(12). The lost activity was, however, always recovered only by ethanol treatment. This indicated that G(12) might interact with cells more strongly by means of a hydrophobic force than an electrostatic one. The antimicrobial spectrum showed that G(12) was effective against not only bacteria but also yeasts.