A new technique with a quantum microscope makes it possible to see on a nanometric scale and does so with living cells
To the delight of scientists (and perhaps not so much of the microorganisms that end up on the slide), we have been up to date when it comes to microscopes lately. It is especially interesting when it comes to exceeding the resolution limits in live samples, and in this case it is view living cells in unprecedented detail, according to this team of researchers.
In fact, we were recently talking about a technique to view individual atoms. In this case, the technique allows cells to be observed at the nanoscale without having to destroy them. not needing vacuum like an electron microscope, which normally have much higher resolution than generic optics (which do not require a vacuum and allow you to observe live samples).
Using paired photons
Normally, when you see living cells under a light microscope, you see something like this, greatly magnified, with limited resolution and without staining. The resolving power is limited and talking about nanometers is more of an idea, because what we see is in micrometer scale (1 millimeter = 1,000 microns (µm) = 1,000,000 nanometers (nm)).
Just as a cell is measured in micrometers, to measure its structures we use smaller units such as nanometersFor example, to talk about the diameter of the filaments that make up its skeleton or the thickness of the membrane, which is what we see as a line or wall (properly speaking) in previous cells. And it is precisely on this scale that they have focused with this new technique.
This is a work by researchers from the universities of Queensland (Australia and Rostok (Germany) published in Nature, using two laser beams, directing one to pass through a glass designed for the process. This crystal “squeezes the light”, that is, it makes the photons pair up in correlated pairs, thereby noise is reduced and more detail is achieved.
It is the principle of quantum entanglement, hence the talk of quantum microscope. The entanglement is the association of two particles with interdependent properties, so that by measuring one photon it is possible to know when the next one will arrive.
The team talks about a improved contrast and quality, showing micrographs of polystyrene droplets and yeast cells. It is not the image that we would obtain with a scanning electron microscope, but it must be taken into account that the yeasts were alive and some organelles and the cell wall are appreciated, showing a resolution of 200 nanometers.
It is a lower resolution than that of the solution we saw with the hyperbolic material coating, but it is certainly a striking achievement. Of course, for its commercialization it is still necessary to solve certain technical obstacles, as they describe, although they consider the experiment as clear proof that quantum techniques can be a good resource to better understand and understand biological processes.
Image | University of Queensland