Robotic tweezers that can grasp a cell without damaging it, and are smart enough to know how hard to grasp its target, has been developed by scientists at the University of Toronto.

Designed from a silicon wafer, the robotic tweezers, which look similar to a razor blade, use a pair of arms 3mm long to clamp around cells up to 10 micrometers across and apply a minimum force of 20 nanoNewtons. Typically pressure needs to be above 100 nanoNewtons before a cell starts to deform.

Once programmed, the tweezers can be left alone and will recognise the difference between the shape of a cell (if this is what the device has been programmed to recognise) and other bodies. The device is also aware of its own grip strength, and can increase or decrease it to ensure a secure grip that won’t damage the cell.