Synthesis and biological activity of 8-hydroxyquinoline and 2-hydroxypyridine quaternary ammonium salts

Two series of quaternary cationic surfactant were synthesized by reaction of 8-hydroxyquinoline and 2-hydroxypyridine with long chain alkyl halides (dodecyl, tetradecyl- and hexadecyl-bromide). Surface tension was measured in aqueous solution for different concentrations at 25 degrees C. Various surface properties of the synthesized surfactants were evaluated, particularly critical micelle concentration (CMC), efficiency (Pi(CMC)) as well as maximum surface excess (Gamma(max)) and minimum surface area (A(min)). Micellization and adsorption in liquid/air interfaces thermodynamics were investigated. The synthesized cationic surfactants were evaluated for their biocidal activity. All compounds prepared showed good antibacterial and antifungal activities.