Unilamellar Lipid Bilayers as Vehicles for Azo Disperse Dyes on Wool

Abstract

Unilamellar phospholipid vesicles have been examined as carriers for azo disperse dyes applied to untreated wool fibers. Liposomes were prepared with egg phosphati dylcholine and contained CI disperse orange 1 at different phospholipid/dye concen trations. The physical stability of these systems was assessed by measuring the mean vesicle size distribution of liposome suspensions after preparation and during the dyeing process. Kinetic aspects involving dye adsorption and bonding on untreated wool samples by means of unilamellar liposomes at different dye/lipid molar ratios were also investigated. This process leads to the controlled exhaustion of dye in wool fibers, which depends directly on the relationship existing between the dye and phospholipid components in liposomes, improving dye adsorption and dye-fiber bonding. The dis persing efficiency of these systems as regards the use of conventional dispersing agents has been also improved. The optimum application for both dye exhaustion and total amounts of dye bonded to the untreated wool fibers correlates directly with the dye / phospholipid weight ratio, corresponding to the maximum level of dye encapsulation efficiency of these systems in the range of phospholipids and dye studied.