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Intermolecular interactions between surfactants and cationic dyes and effect on antimicrobial properties / Nastaran Hashemi in Industrial & engineering chemistry research, Vol. 49 N° 18 (Septembre 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 18 (Septembre 2010) . - pp. 8347–8352 Titre : Intermolecular interactions between surfactants and cationic dyes and effect on antimicrobial properties Type de document : texte imprimé Auteurs : Nastaran Hashemi, Auteur ; Gang Sun, Auteur Année de publication : 2010 Article en page(s) : pp. 8347–8352 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Cationic  molecules Résumé : Cationic molecules can interact with anionic and other cationic species in solutions. Electrostatic and hydrophobic interactions between two series of cationic antimicrobial dyes and several surfactants were studied using a UV−vis spectrophotometer. The dye containing more cationic charges with a short alkyl chain showed stronger binding power with surfactants than the one with less positive charge, while the ones with longer chains exhibited lower binding energy. These dyes could form complex structures with anionic surfactant species in solutions at very low concentrations of the surfactant (far below critical-micelle-forming concentrations of the surfactants), which was revealed from the changes in absorbance and wavelength of the maximum absorbance (λmax) of photospectrometry. However, when the concentrations of surfactants were above their critical micelle concentrations, the dyes could redissolve and dissociate into molecular or ionic forms. Such results were confirmed by conductivity and antimicrobial functions of the solutions. These findings are useful in understanding the impact of anionic surfactants on cationic antimicrobial agents. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie101001d [article] Intermolecular interactions between surfactants and cationic dyes and effect on antimicrobial properties [texte imprimé] / Nastaran Hashemi, Auteur ; Gang Sun, Auteur . - 2010 . - pp. 8347–8352. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 18 (Septembre 2010) . - pp. 8347–8352 Mots-clés : Cationic  molecules Résumé : Cationic molecules can interact with anionic and other cationic species in solutions. Electrostatic and hydrophobic interactions between two series of cationic antimicrobial dyes and several surfactants were studied using a UV−vis spectrophotometer. The dye containing more cationic charges with a short alkyl chain showed stronger binding power with surfactants than the one with less positive charge, while the ones with longer chains exhibited lower binding energy. These dyes could form complex structures with anionic surfactant species in solutions at very low concentrations of the surfactant (far below critical-micelle-forming concentrations of the surfactants), which was revealed from the changes in absorbance and wavelength of the maximum absorbance (λmax) of photospectrometry. However, when the concentrations of surfactants were above their critical micelle concentrations, the dyes could redissolve and dissociate into molecular or ionic forms. Such results were confirmed by conductivity and antimicrobial functions of the solutions. These findings are useful in understanding the impact of anionic surfactants on cationic antimicrobial agents. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie101001d