Supersensor for early cancer diagnosis
Researchers at Case Western Reserve University in Cleveland, Ohio, working under the guidance of Professor Giuseppe Strangi, have developed an optical biosensor for cancer diagnosis based on nanostructured materials, the sensitivity of which is a million times higher than the sensitivity of earlier versions.
The device, which fits in the palm of the hand, will provide oncologists with the opportunity to identify single molecules produced by cancer cells circulating in the bloodstream. This will allow doctors to conduct an unprecedented early diagnosis of certain types of cancer, monitoring the effectiveness of therapy and tumor resistance, and much more.
According to the authors, at the early stages of tumor development, most cancer cells circulating in the bloodstream express proteins with a very low molecular weight, not exceeding 500 daltons. These proteins are usually too small and their concentration is too low to detect using existing methods, which leads to false-negative results.
Using the new platform, the researchers were able to identify protein molecules with a molecular weight of 244 daltons in a very diluted solution, which, according to the developers, will allow doctors to diagnose cancer much earlier than is currently possible.
To achieve such an unprecedented sensitivity, the authors had to overcome a number of difficulties. One of the biggest problems was the inability to detect objects with the help of light waves whose size is smaller than their own physical dimensions, the minimum value of which corresponds to about half a micron. In addition, in diluted solutions, molecules drift randomly, which causes a very low probability of their hitting the sensor surface.
The developers managed to overcome these barriers by combining nanotechnology tools and microfluidic systems, as a result of which a sensor based on the so-called hyperbolic metamaterial was created. The exceptional sensitivity of this sensor is due to the fact that when in contact with a small molecule, its surface undergoes significant local changes, leading to a shift in the spectrum of reflected light waves.
Depending on the size of the molecule, the spectrum of reflected waves shifts by different values. The authors hope that in the future this will allow identifying specific biomarkers not only for tumors of different organs, but also for different types of tumors of the same organ. They are currently testing a new sensor as a tool for early diagnosis of prostate cancer.
Article by Giuseppe Strangi et al. Extreme sensitivity biosensing platform based on hyperbolic metamaterials is published in the journal Nature Materials.
Evgeniya Ryabtseva
Portal "Eternal youth" http://vechnayamolodost.ru based on Medical News Today: Researchers develop a supersensitive biosensor for cancer.
11.04.2016