This paper presents the evaluation of ultra-minimal spout amount from micro-nano pipettes into phospholipid-coated micro-droplets. The micro-nano pipettes can be used for various biological applications, such as single cell analysis. Conventional microinjection with pipettes has been conducted by air pressures. However, the spouting of high viscosity solutions, such as biological protein solutions, is relatively difficult due to the frictional forces between the surface of a pipette and a solution. It is also needed to evaluate the spout amount quantitatively. In this paper, the electro-osmotic phenomenon is applied to spout the high-viscosity biological protein solution. The local spouts of protein solutions, GFP and F-actin, are demonstrated experimentally. The amount of spout solution is quantitatively evaluated from the fluorescent intensity inside a phospholipid-coated micro-droplet.
