Effect of Temperature and Surfactant on the Control Release of Microencapsulated Dye in Lecithin Liposomes. I

Abstract

The objective of our work has been the microencapsulation of dyes with lecithin from soybean, with the formation of liposomes, as a substitute for synthetic auxiliaries so as to improve the quality of the effluent. Current scenarios promote the disintegration and leakage of the liposomes, such as, changes in temperature, pH and the use of surfactants. Since dyeing process is a mix of all these parameters, we pretended to study each one separately. Rhodamine 6G fluorescence is known to be concentration quenched through the formation of non-fluorescent dimmers and, additionally, through the energy transfer from rhodamine monomer to these dimmers (Baptista ALF, Coutinho PJG, Real Oliveira MECD, Gomes JINR. Proceedings of 13th International Symposium of Surfactants, SIS 2000, Gainesville, USA, 2000). The temperature, the surfactant and pH induce a release of the encapsulated dye resulting in rhodamine dilution and consequently alterations in the dimerization/binding equilibrium. The experimental spectra indicate that rhodamine binds almost completely to liposomes. The decomposition of the rhodamine fluorescence spectra allowed us to determine the percentage of released dye during a simulated dyeing process, and allowed us to conclude that the dimerization process occurs mainly at the inner interfaces. The amount of dye released induced by temperature changes was greater in the presence of surfactant.

Design, Development and Optimization of Nimesulide-Loaded Liposomal Systems for Topical Application

“…This may be assignable to the surface activity of the PC [40]. Numerous studies vouch for drug release enhancement attribute of phospholipids [41][42].…”

The effect of liposome on dyeing mohair/wool blends

“…Dyeing at low temperatures with the help of liposomes gives a more natural handle and improves the quality properties of fibres . Liposomes are known to be readily biodegradable, which makes them environmentally friendly . Liposomes release the encapsulated dyes slowly, promoting a retarding effect, comparable with the one obtained with retarding agents, thus making them a good alternative to commercial dye auxiliaries when used as an encapsulating agent for dyes.…”

Low-Salt or Salt-Free Dyeing of Cotton Fibers with Reactive Dyes using Liposomes as Dyeing/Level-Dyeing Promotors

“…Liposomes have been examined as a means of delivering dyestuffs to fibers in a cost-effective and environmentally sensitive manner 14 . Compared with traditional retarding agents, liposomes can slowly release a microencapsulated dye to increase the retarding effect, making them a good alternative to commercial levelling agents 15 . Several papers have reported potential applications of liposomes for wool and wool/polyester mixture dyeing.…”

“…Several papers have reported potential applications of liposomes for wool and wool/polyester mixture dyeing. Liposomes have been investigated as vehicles in wool dyeing with acid, disperse and metal-complex dyes, and wool and wool blend dyeing with liposomes resulted in better quality and energy savings and lower environmental impact 5,15–18 . The main advantages of using liposomes are an obvious reduction in the dyeing temperature (lower by approximately 10 °C compared with that of a traditional wool dyeing process); improved fiber quality, smoothness and mechanical properties of the dyed fibers; and an obvious reduction in the contamination load of the dye bath 6,19,20 .…”