On-chip robotics for biomedical innovation: Manipulation of single virus on a chip

Nanomanipulation of a single influenza virus in a microfluidic chip for biomedical innovation was developed. We employed Robot on a Chip (RoC) to achieve stable manipulation of nano-scale biomaterials such as virus (size is about 100 nm). The microfluidic chip has independent virus chamber and cell chamber to make quantitative analysis such as single virus infection to a specific cell. Gel-microtool generated by local heating of thermosensitive hydrogel poly(N-isopropylacrylamide) (PNIPAAm) by near infrared laser was used for stable and high-speed virus manipulation. Single selected virus was transported to cell chamber using the gelmicrotool. To construct the stable experimental environment in a microfluidic chip, solution reservoir having air damper and leak port was fabricated and short response time of flow control within 1 second was achieved. To avoid the incursion of the extra virus to the cell chamber, isolation of the cell chamber to virus chamber was performed by stacking the microchannel between these chambers using in-situ photoplolymerization of photo-crosslinkable resin polyethylene glycol methacrylate (PEG-MA) (200). In this paper, we demonstrated single influenza virus manipulation and isolation of cell chamber and virus chamber using optical tweezers, quick flow control devices and in-situ photopolymerization in a microfluidic chip.