Moscow: A research team from HSE University, Skoltech, MPGU and MISIS have developed nanophotonic-microfluidic sensors whose potential applications include detection, monitoring and evaluation of treatment success. Today, the device can detect dissolved gases and liquids in low concentrations with high precision. Appeared in the study Optics Letters.
According to the World Health Organization, the global cancer burden in 2020 is estimated to be 19.3 million new cases and 10 million deaths. WHO experts believe that an estimated 30% of new cases can be prevented, and with the same relatively early investigation, can be cured.
Today, the lab-on-a-chip is a miniature sensor device capable of performing complex biochemical analysis that is considered one of the most promising approaches for early detection of cancer. Russian researchers have developed a new hybrid nanophotonic-microfluidic sensor for extremely sensitive analysis of liquids and gases at very low concentrations in solutions.
Says Gregory Goltsman, HSE MIEM Professor, “Our study is an important step towards building a compact lab-on-a-chip device that can detect not only a complete set of blood tests but also early stage cancer biomarkers. Dosage. Ideally, our goal is to create a small portable device that requires only a drop of blood. At the push of a button, the doctor will see the results, for example the parameters are normal or more tests are needed. ”
The current device includes a nanophotonic optical sensor on the chip in combination with microfluidic channels above the surface of the sensor. Fluids or gases pumped through channels affect the propagation of optical radiation in highly sensitive nanophotonic devices, thereby altering the spectral characteristics of the output. By examining these changes, researchers can determine the composition of the sample.
The distinctive feature of the device is the small size of the microfluidic channels that deliver the samples to the sensors. This makes it possible to obtain results even from very small samples, which can be important when on-site analysis is not possible and samples must be transported elsewhere for examination.
Human blood contains certain components that may be valuable for early diagnosis of oncological diseases. Such components include extracellular vesicles (exosomes). Exosomes are microscopic vesicles released into the intercellular space by tissue and organ cells.
‘Cells communicate with each other using extracellular vesicles like exosomes to send messages’, says Dmitry GorinProfessor at Skolkovo Institute of Science and Technology. However, certain factors – either internal (genetic predisposition) or external (environmental, such as radiation) – can disrupt the normal functioning of the cell, causing it to send false messages, leading to uncontrolled cell division and tumor growth.
In the early stages of cancer, exosome blood concentrations rise to reach analytically significant values, indicating the presence of cancer, thus making these exosomes potentially useful biomarkers in oncology. The research team plans to further refine their device so that it can be used for this method of cancer screening.
So far, the sensors have been tested not on blood samples but on water solutions of isopropyl alcohol in 20 different concentrations, ranging from 0.08% to 72% by weight. Since alcohol is very soluble in water, it was possible to use very low concentrations. For example, the sensor detected isopropanol in a solution containing 12 molecules of alcohol per 1 million molecules of water. Currently, the device can only analyze two-component solutions, but the authors plan to make it suitable for multi-component analyzers by covering specific receptors (adapters, antibodies, DARpins and peptides) on the surface of the sensor using microfluidic channels.
‘Today, the practical equipment required to operate the device is very wide. The setup includes a peristaltic pump, a tunable laser, a photodetector, a chip and a PC for processing data ‘, explains Alexei Kuzin, author of the paper, a HSE graduate and current doctoral student at Skoltech. “In the future, we hope to create a compact and portable device for rapid testing that will reduce the time and cost of cancer diagnosis, monitoring and treatment response evaluation.”