Platform can be used to form a diagnostic device which can provide early warning signs for lung disorders
Researchers at the Indian Institute of Technology (IIT)-Bombay have developed a platform that can sniff out the presence of cancerous cells in the lungs from the breath of a person.
The two-member team from IIT-B claims that certain chemicals exhaled through breath are indicative of lung cancer but are not detected by a breath test. The team have developed a system that claims to detect such chemicals in single molecular levels in about a minute.
Two types of techniques to detect a chemical substance
Chandramouli Subramaniam, a professor from the institute’s Department of Chemistry told that there are two types of techniques to detect a chemical substance (an analyte) which are indirect and direct.
In the indirect method, other molecules called labels specifically bind to the analyte and emit a fluorescent light which is detected. In the direct method, the light scattered by the analyte itself has a specific signature that is detected. He also added that their new platform uses the direct method called the Raman spectroscopy.
SERS to enhance the intensity of light
Subramaniam claimed that the intensity of the light collected in Raman scattering is low and to overcome this, scientists have developed a method called Surface Enhanced Raman Scattering (SERS). However, getting a reliable signal has been a problem as the nanoparticles are mobile due to Brownian motion of these colloids. To overcome this problem, researchers have made a cage of nanoparticles to trap the analytes.
The newly designed platform utilised the concept that any solid substance will always have a layer of molecules in vapour phase at its surface. This process helped the platform to sniff substances like TNT in its solid form. It identified TNT in the presence of similar, non-explosive but chemically similar substances like DNT (dinitrotoluene) and nitrobenzene. In addition to this, the platform can also be used to make portable spectrometers.
He also mentioned that they are in discussion with an Indian company to develop a handheld Raman spectrometer. They can couple it with their SERS platform to form a diagnostic device which will enable them to provide early warning signs for lung disorders.
Well, this same platform can also be used to monitor air pollution levels or detect explosives such as TNT (trinitrotoluene). The research project was funded by the Department of Science and Technology’s Nano-mission programme.