27 research outputs found
Responsive Giant Vesicles filled with Poly(N-isopropylacrylamide) Sols or Gels
4 pagesInternational audienceWe prepared giant unilamellar vesicles (GUVs) enclosing solutions or covalent gels of Poly(Nisopropylacrylamide) (PolyNipam). Concentrated suspensions of GUVs were prepared by applying an alternative field on a lipid film hydrated by a monomer solution containing N-isopropylacrylamide, crosslinker (N,N-methylene-bis-acrylamide), initiator and sucrose. Vesicle inner medium was polymerised and crosslinked by UV irradiation of the suspension, yielding viscous vesicles enclosing a solution of linear PolyNipam chains (when no bisacrylamide was used) or elastic vesicles filled with a covalent PolyNipam gel. We show that gel-filled vesicles are responsive systems triggered by the temperature: they shrink, reducing by a factor eight their volume below the critical temperature (32 â—¦C in water, lower in glucose solution) and re-swell in a reversible and reproducible way upon decreasing temperature. In both cases, we show that the vesicle lipid membrane interacts with the internal polymer, resulting in an strong resistance of the vesicles to external mechanical stresses (enhanced tension of lysis)
Stabilization of liposomes against stress using polyelectrolytes: interaction mechanisms, influence of pH, molecular weight, and polyelectrolyte structure
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Stabilization of liposomes by polyelectrolytes: mechanism of interaction and role of experimental conditions
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Experimental characterization of liposomes stabilized by polyelectrolytes and mechanism of interaction involved
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Influence of molecular weight and ph on adsorption of chitosan at the surface of large and giant vesicles
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Influence of polyelectrolyte chemical structure on their interaction with lipid membrane of zwitterionic liposomes
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Decoration of lipid vesicles by polyelectrolytes: mechanism and structure
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Use of the LSBB to develop a new method of natural tracing using organic matter
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Large and giant vesicles 'decorated' with chitosan: effects of pH, salt or glucose stress, and surface adhesion
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