Jul 9 2019
A novel and non-invasive approach for controlling cells using microrobotics has recently been demonstrated by researchers in the lab of Professor Aaron Wheeler (Chemistry, IBBME). Details of the new research can be found in the Proceedings of the National Academy of Science.
Shuailong Zhang (left) and Aaron Wheeler, have designed microrobots (working at the sub-millimeter scale) that can be operated by optoelectronic tweezers for cell manipulation. (Photo credit: Dan Haves)
Cell manipulation — which entails transferring small particles from one place to another — is an integral part of several scientific endeavors. One technique of manipulating cells is via optoelectronic tweezers (OET), which use different light patterns to directly interact with the object of interest.
Owing to this direct interaction, there are boundaries to the force that can be applied and speed in which the cellular material can be exploited. This is where the use of microrobotics becomes beneficial.
Led by postdoctoral fellow Dr. Shuailong Zhang (Chemistry) and Wheeler, the scientists have developed microrobots (operating at the sub-millimeter scale) that can be worked by OET for cell manipulation.
Rather than using light to directly interact with the cells, the light is used to navigate cogwheel-shaped microrobots that can “scoop up” cell material, move it, and then deliver it. This manipulation can be achieved at higher speeds while causing less harm to the material compared to traditional OET techniques.
The ability of these light-driven microrobots to perform non-invasive and accurate control, isolation and analysis of cells in complex biological environment make them a very powerful tool.
Dr. Shuailong Zhang, Postdoctoral Fellow, University of Toronto
“Traditional techniques that are used to manipulate single cells while evaluating them by microscopy is slow and tedious, requiring a lot of expertise to carry out,” says Wheeler, who is also cross-appointed to the Donnelly Centre for Cellular and Biomolecular Research.
“But these microrobots are inexpensive and very simple to use and they have a wide range of applications in the life sciences and beyond.”
Besides cell analysis, the microrobots can also be used in RNA sequencing, cell sorting (for clonal expansion), and cell-cell fusion (usually used in the making of antibodies).
“Neural stem cells are responsive to a multitude of cues and environmental stimuli in their niche, and these change with injury, so teasing out the signals, and cell responses, is a huge challenge when we are trying to harness the potential of stem cells for neural repair,” says Professor Cindi Morshead (IBBME, Surgery), who is the study’s co-author. Her study in regenerative medicine works with neural stem cells that are located in the spinal cord and brain.
“These microrobots allow for the exquisite control of the cells and their microenvironment, tools that we will need to learn how best to activate the stem cells.”