Most conventional light microscopes have a resolution of 200 nanometers – this means that imaged objects which are any closer to one another won't be seen as separate items. A new high-tech microscope slide, however, boosts that figure to 40 nanometers.
Developed by scientists at the University of California-San Diego, the slide is coated with a "hyperbolic metamaterial" made up of nanometer-thin alternating layers of silica glass and silver.
When light passes through this coating, its wavelength is shortened, and the light gets scattered to create a speckled pattern. A sample mounted on the slide gets illuminated from numerous angles via this speckled short-wavelength light pattern, resulting in series of low-resolution images of that sample. A linked computer subsequently utilizes a reconstruction algorithm to combine those separate images, producing one composite high-resolution image.
As a result, an ordinary light microscope using one of the slides is able to image much smaller objects than was previously possible. In tests conducted so far, the slide enabled such a microscope to image individual actin protein filaments in fluorescently labeled cells, and to image microscopic fluorescent beads and quantum dots which were spaced 40 to 80 nanometers apart.
![One of the slides being used in an ordinary light microscope (also known as an optical microscope)](https://assets.newatlas.com/dims4/default/4822a8e/2147483647/strip/true/crop/900x819+0+0/resize/900x819!/quality/90/?url=http%3A%2F%2Fnewatlas-brightspot.s3.amazonaws.com%2Fca%2F8a%2Fe7e7924b4695ad953551805d0c6a%2Fsuper-res-microscope-slide-2.jpeg)
The scientists are now adapting the technology to image subcellular structures within living cells. Ordinarily, an electron microscope would be required in order to image such tiny structures – even then, it couldn't do so in a living cell, as its samples would have to be placed within a vacuum chamber.
A paper on the research, which is being led by Prof. Zhaowei Liu, was recently published in the journal Nature Communications.