Absorption and fluorescence studies on interaction between cationic dyes and Klebsiella K7 capsular polysaccharide.

No Thumbnail Available
Date
1992-06-01
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Interaction of cationic dyes, pinacyanol chloride, acridine orange and phenosafranin, with Klebsiella K7 capsular polysaccharide has been investigated by spectrophotometric and spectrofluorometric measurements. The acidic polysaccharide induce a metachromatic blue shift of the absorption band of pinacyanol chloride from 600 nm to 495 nm, indicating strong metachromasy. Stoichiometry of polyanion and dye cation (1:1.5) in the polymer-dye compound formed by the interaction between pinacyanol chloride dye and K7 polymer indicate that both glucuronic acid and pyruvic acid act as the potential anionic sites for interaction. Both spectrophotometric titration of pinacyanol chloride and spectrofluorometric titration of acridine orange and phenosafranin dyes by the polymer gave quite comparable equivalent weights for the polymer. Dye-polymer interaction studies indicated induction of metachromasy in the cationic dye by the anionic biopolymer, establishing its chromotropic character.
Description
Keywords
Citation
Mitra A, Chakraborty AK. Absorption and fluorescence studies on interaction between cationic dyes and Klebsiella K7 capsular polysaccharide. Indian Journal of Biochemistry & Biophysics. 1992 Jun; 29(3): 291-5