What is the best way for scientists to study things like blood cells, algae, and bacteria up close and personal? If your answer involves putting a sample of it on a glass slide and then looking at it under a microscope, move over gramps because there is now a more exciting, high-tech way of doing it!
What physicists at Bielefeld University and Goethe University Frankfurt have developed is a technique calling for a Star Trek-style tractor beam which can hold biological cells in place so they can be examined at extremely high resolutions.
“In this work we’ve been able to hold cells by optical forces while taking micrographs of the same cells with very high spatial resolution,” Professor Thomas Huser, head of Bielefeld’s Biomolecular Photonics Research Group in the Faculty of Physics, told Digital Trends. “[Current methods of looking at biological samples] makes it difficult to study cells that do not adhere or do not like to adhere to such materials. [These include] blood cells, bacteria, or other cells that ‘swim’ in water-like solutions. To take images with very high resolution, these cells have to be pulled onto a substrate, which is an unnatural environment for them and often changes their behavior.”
Using the new tractor beam technology (also referred to as an “infrared optical tweezers system”), biological samples do not suffer these alterations to their natural behavior. Better yet, they can be turned and rotated — and the beam is even able to act as an extended hand for making microscopically small adjustments.
Thanks to the method, researchers are able to study the 3D structure of genetic material at a resolution of circa 0.0001 millimeters.
“We developed this system specifically so we will eventually be able to follow infectious disease processes, [such as] the transmission of a virus from an infected cell to an uninfected cell, in situ,” Huser said “The optical nanoscope will enable us to resolve single virus particles, while the optical tweezers allows us to manipulate infected cells safely and make deliberate contact of infected cells with uninfected cells. In general, this unique combination is useful for studying any cell-cell interaction processes in a very controlled manner with the highest possible spatial resolution. Once this has been established it can also be used [in applications like] cellular assays to screen for pharmaceuticals that disrupt cell-cell interactions.”