Microfluidic device for combinatorial fusion of liposomes and cells

We describe an electrofusion-based technique for combinatorial synthesis of individual liposomes. A prototype device with containers for liposomes of different compositions and a fusion container was constructed. The sample c ontainers had fluid contact with the fusion container through microchannels . Optical trapping was used to transport individual liposomes and cells thr ough the microchannels into the fusion container. In the fusion container, selected pairs of liposomes were fused together using microelectrodes. A la rge number of combinatorially synthesized Liposomes with complex compositio ns and reaction systems can be obtained from small sets of precursor liposo mes. The order of different reaction steps can be specified and defined by the fusion sequence. This device could also facilitate single cell-cell ele ctrofusions (hybridoma production). This is exemplified by fusion of transp orted red blood cells.