GIANT UNILAMELLAR VESICLES AS A PLATFORM OF LIQUID HANDING IN FEMTOLITER VOLUMES

摘要

This paper describes the potential utilization of giant unilamellar vesicles (GUVs) as a platform of handling chemical/biochemical reagents in femtoliter volumes. GUVs with diameter 1~10 μm containing chemical reagents together with polymers (e.g., PEG and dextran) are prepared, which were then subjected to electrofusion. We show that, after mixing of reagents via fusion, the fused GUV spontaneously deform to a budding shape, separating the enclosed solution into subvolumes. We confirmed that this transformation is a result of maximizing translational entropy of the encapsulated polymers (depletion volume effect). This physical phenomenon has several interesting features; 1) It allows aliquoting liquids in femtoliter volume, which are difficult in the droplet-based systems. 2) Encapsulated polymers are chemically inert, thus providing a universal platform. 3) Biomimetic features of the lipid vesicle membrane and encapsulated polymers are suitable especially for studying biochemical reactions in the volume comparable to living cells.