Robotic cell transportation system based on micropipette resistance modeling

Cell transportation, using a micropipette to pick and place cells from one droplet to another, is a key step in many cell engineering applications. However, most of the current cell transportation operations rely on microscope vision guidance, unsuitable for the future integrated and automated cell engineering applications where microscopic views are usually missed. The presenting microscopic view-free cell transportation systems are only applicable for special giant cells due to the bilayer structure of operation micropipettes. In this paper, a robotic cell transportation system based on micropipette resistance modeling was developed to transport common-sized cells without a microscopic view. First, a narrow-necked micropipette (NNM) was fabricated for holding the target cell inside the micropipette during transportation. Then, a gap resistance model, an aspiration resistance model, and an injection resistance model of the micropipette were developed to land on the cell plane, pick and release the cell without a microscopic view, respectively. Based on the above work, a robotic transportation process was established to transport the common-sized cells without a microscopic view. Finally, experimental results demonstrate that the proposed system can land on the cell plane with 100% success rate. It can transport 10 μm-level sized HeLa cells and 100 μm-level sized porcine oocytes with efficiencies comparable to common microscopic view-based methods and without harm to cell survival rate. Our microscopic cell transportation system can be upgraded to a high-throughput version for integrated automated cell engineering applications in the future.