Uniform-sized Proteoliposome Formation by Using Electrospray for Microscopic Membrane Protein Assays

This paper describes an instant formation method of uniform-sized proteoliposomes for membrane protein assays using fluorescence microscopy. The applied electrospray technique was the same as our previous works [1], although here we directly sprayed proteovesicles (<1 μm size) dispersed in “an aqueous buffer” and micropatterned them on a substrate; technical problems/conditions of the electrospray using aqueous buffers were accommodated (Fig. 2d). Hydration of the protein/lipid micropattern instantly produced a uniform-sized proteoliposome array. Moreover, the assay results indicated that the target protein FoF1 was integrated on the liposomal membrane and its transport function may be preserved after the rehydration.