"Analytical tools to study exocytosis and membrane dynamics on the nanoscale"
Department of Chemical and Biological Engineering
Chalmers University of Technology
In our lab, we develop analytical tools and cell models to learn more about basic cell function and neurochemistry. In one area, we study enzyme-nanoparticle conjugates and use these constructs as scaffolds to develop ultra-small enzyme-based biosensors for detection of non-electro active neurotransmitters released by cells. We also develop artificial cell models based on giant unilamellar liposomes (GUVs) that we use to study membrane dynamics in exocytosis. An artificial cell model has recently been used to microinject 150 nanometer unilamellar vesicles into giant unilamellar vesicles and to monitor spontaneous vesicle fusion to the artificial cell membrane via a DNA zipper. Subsequent chemical release from these nanometer vesicles has been measured with amperometry.
With the tools of microinjection combined with electroporation, lipid nanotubes can be pulled to the inside of an artificial cell constructed from a GUV. The inner diameter of such a lipid nanotube has recently been determined by amperometrically measuring electroactive species as they diffuse through the tube while simultaneously monitoring the length using microscopy. We have also used this membrane cell model to determine the size of lipid nanotubes and study how membrane composition dynamically affects the size of lipid nanotubes.