A team of scientists have developed a test on a chip that can give diagnostic information from blood or urine samples much faster and more conveniently than current methods.
In the paper, published yesterday in Nature Nanotechnology, the authors explain that this test allows for label-free analysis of molecular interactions. This is achieved using a chip with striped dots; antibodies bind to the stripes, but the space in between remains clear. If the antibody is bound and light is passed through the chip, the light will bend showing a pattern on a point below the chip. In the absence of binding, no diffraction occurs.
The scientists noted that this technique makes use of the wave character of light in much the same way a hologram does. Thus they named the striped pattern “mologram” (short for molecular hologram) and the new diagnostic technique “focal molography”.
One advantage of this technique is that washing steps are not necessary, making it substantially faster than other diagnostic tests. Right now each chip has 40 molograms that measure a single molecular marker, but the researchers believe this technology may someday be used to measure a different marker on each mologram, allowing for rapid diagnosis for multiple conditions.
In order to develop the chip, a diverse group of experts from ETH Zurich and Roche worked together. Among them were experts in photochemistry, chip manufacturing and surface coating. The group plans to continue this collaboration and are now focused on bringing the new technology to market.
Image: Laser light propagates in a thin-film waveguide and, if the molecules under examination bind to the mologram, it is deflected there and focused onto a focal point. Image courtesy of Gatterdam et al. Nature Nanotechnology 2017