Optically Powered Milli-Scale Robot System for Nanoliter Fluid Delivery Based on Diamagnetic Levitation

We demonstrate the use of a milli-scale robot setup to manipulate and transport nanoliter fluids based on diamagnetic levitation. Pyrolytic graphite (PyG) samples have been shown to passively levitate over permanent magnets with alternating poles and can be translated by low-power optical irradiation. Micropipettes attached to the surface of PyG samples are used to load fluids via capillary action and unload those fluids into an agarose, tissue-like gel through diffusion. The system features minimum friction and contact as well as simple actuation and control processes. This proof-of-concept demonstration paves the way for contactless nanoliter fluid delivery applications with temporal and spatial precision.