Osmotic Shrinking of Vesicles Embedded in Hydrogels

Lipid vesicles can be dispersed in various gel matrices as an encapsulation technology and as a model system for cells supported by an extracellular matrix.

By using confocal fluorescence microscopy on Giant Unilamellar Vesicles (GUVs) embedded in an agarose hydrogel matrix, we can observe changes in the liposome shape under hyperosmotic shocks.

Compared to free floating vesicles, gel-supported vesicles show irregular shapes during shrinkage. The results from our simple model system are reminiscent of plant cell plasmolysis.

We propose that the observed membrane shapes are caused by a non-specific adhesion between the membrane lipids and the agarose gel matrix. By varying the membrane-gel contact (chemical or physical), the strength of the gel and the osmotic shock, we want to explore the analogy between our system and biological systems, and use the effects to create functional hydrogels.