Robot-assisted automatic cell sorting with combined optical tweezer and microfluidic chip technologies

This paper presents a robot-assisted methodology that integrates optical tweezer and microfluidic chip technologies to realize automatic cell sorting from small sample population. The microfluidic chip used for cell sorter is designed and fabricated, and the flow environment within the microfluidic channel is investigated with simulation. Two image processing methods, depending on size and fluorescence label respectively, are used to recognize the target cells. With robotic manipulation of optical tweezers, the target cells can be moved to the desired area. Motions of optical tweezers are further analyzed for improvement of transportation efficiency. The relationship between the laser power and the cell maximum moving velocity is analyzed such that the robust cell sorting with as low power as possible can be achieved. Experiments on sorting yeast cells are performed to demonstrate the effectiveness of the proposed cell sorting approach.