title: Controllable electrofusion of lipid vesicles: initiation and analysis of reactions within biomimetic containers.
abstract: We present a microfluidic device that is able to trap multiple giant unilamellar vesicles (GUVs) and initiate electrofusion via integrated microelectrodes. PDMS posts were designed to trap and isolate two or more vesicles. Electrodes patterned onto the glass surface of the microchannels are able to apply a short, high voltage pulse across the traps for controllable electrofusion of the GUVs. The entire array of traps and electrodes are designed such that an average of 60 individual fusion experiments can be performed on-chip. An assay based on Förster resonance energy transfer (FRET) is performed to show successful lipid mixing. Not only can the device be used to record the dynamics of lipid membrane fusion, but it can be used for reaction monitoring by fusing GUVs containing reactants. We demonstrate this by fusing vesicles encapsulating femtolitre volumes of cobalt chloride or EDTA and monitoring the amount of the complexation product over time.
authors.affiliation: Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich, 8093, Switzerland. dittrich@org.chem.ethz.ch.
authors.forename: T
authors.initials: T
authors.lastname: Robinson
authors.forename: P E
authors.initials: PE
authors.lastname: Verboket
authors.forename: K
authors.initials: K
authors.lastname: Eyer
authors.forename: P S
authors.initials: PS
authors.lastname: Dittrich
mesh_terms: D040761:Biomimetic Materials; D002614:Chelating Agents / Q000737:chemistry; D003035:Cobalt / Q000737:chemistry; D056831:Coordination Complexes / Q000032:analysis; D004129:Dimethylpolysiloxanes / Q000737:chemistry; D004492:Edetic Acid / Q000737:chemistry; D055664:Electrochemical Techniques / Q000295:instrumentation*; D004867:Equipment Design; D031541:Fluorescence Resonance Energy Transfer; D007700:Kinetics; D008422:Materials Testing; D008561:Membrane Fusion; D008832:Microchemistry / Q000295:instrumentation; D008839:Microelectrodes; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation*; D008855:Microscopy, Electron, Scanning; D010316:Particle Size; D066330:Printing, Three-Dimensional; D013499:Surface Properties; D053835:Unilamellar Liposomes / Q000737:chemistry*
chemical_list: D002614:Chelating Agents; D056831:Coordination Complexes; D004129:Dimethylpolysiloxanes; D053835:Unilamellar Liposomes; D003035:Cobalt; C013830:baysilon; D004492:Edetic Acid; C018021:cobaltous chloride