Antimicrobial cationic dyes: part 1: synthesis and characterization

As an attempt to combine dyeing and functional finishing in one process, novel antimicrobial cationic dyes were prepared by reacting N,N-dimethylbutylamine, N,N-dimethyloctylamine and N,N-dimethyldodecylamine with anthraquinone derivatives, respectively. The structures of the dyes were fully characterized by using FTIR, H-1-NMR and C-13-NMR analysis. Their color characteristics were studied in terms of lambda(max) and epsilon(max) in aqueous solution. The antimicrobial efficacy of these dyes was evaluated by using a minimum inhibitory concentration (MIC) as an indicator. All of the synthesized dyes showed antimicrobial activities against both Gram-positive and Gram-negative bacteria, but in different levels depending on their structures. The structure-property relationships of the dyes were further discussed. (C) 2003 Elsevier Science Ltd. All rights reserved.