Scientists downsize device used for Raman spectroscopy
New infectious diseases are emerging day by day; finding new medicines and vaccines are the best way to combat those pathogens. However, before drugs can be used as possible treatments, they have to be fastidiously evaluated for many things, including composition, safety as well as purity, etc. Hence, there is a rising need for innovations that can characterize chemical substances in real-time and rapidly.
Scientists from Texas A&M University have currently developed a new technology that can substantially downsize the device utilized for Raman spectroscopy. This known method utilizes light to identify the compounds’ molecular compsition.
Dr. Pao-Tai Lin, assistant professor in the Department of Materials Science and Engineering and the Department of Electrical and Computer Engineering, said that based upon the level of spectroscopic resolution needed, the Raman benchtop setups could be approximately a meter long. A system that can potentially replace these bulky benchtops with a small photonic chip that can easily fit within the tip of a finger is developed by this team.
He added that their innovative photonic gadget likewise has the ability of high-throughput, real-time chemical characterization as well as despite its size – compared to conventional benchtop
Raman spectroscopy systems, it is at least ten times extra sensitive.The outcome of the study is published in the journal Analytical Chemistry.
The Raman spectroscopy is based on the scattering of light by molecules. By absorbing the energy from the incident beam, the molecules dance, rotate, and vibrate when hit by light of a specific frequency. Molecules release a lower-energy light when they lose their excess power. Within a sample, the fingerprints of the molecule are present in the scattered light, known as the Raman spectra.
Lenses and gratings – assortment of optical instruments for manipulating light are present for Raman spectroscopy in the typical benchtops. A lot of space is taken by these “free-space” optical components, they are also a barrier for numerous applications where chemical sensing is needed within small spaces or locations that are difficult to reach. Additionally, for real-time chemical characterization the benchtops can be prohibitive.
Lin and his team turned to tube-like channels, called waveguides, that can transport light with extremely little loss of energy – as an option to conventional lab-based benchtop systems. Aluminum nitride was chosed by the scientists given that it generates a reduced Raman background signal and also is less likely to disrupt the Raman signal coming from a test sample.
The scientists used a technique utilized by industry for drawing circuit patterns on silicon wafers to develop the optical waveguide. Initially, they spun a NR9 – light-sensitive material onto a surface made from silica using UV light, then, they bombarded and coated aluminum nitride along the pattern developed by the NR9 utilizing ionized gas particles, and lastly, using acetone they washed the assembly, leaving behind an aluminum waveguide.
A laser beam was transported via the aluminum nitride waveguide as well as a test sample containing a combination of organic particles was illuminated for evaluating the optical waveguide as a Raman sensor. The scientists discovered while analyzing the scattered light that they might discern each type of molecule within the sample based on sensitivity of at least ten times greater than typical Raman benchtops as well as the Raman spectra.
According to Lin, many optical waveguides could be loaded onto a single photonic chip as their optical waveguides have really fine width, and this architecture is real-time chemical sensing required for the development of drugs and very conducive to high-throughput.
Lin added that their optical waveguide design offers a unique system for checking the chemical composition of compounds continuously, promptly, and reliably. Likewise, these waveguides can be conveniently manufactured at an industrial scale by leveraging the currently existing strategies to make semiconductor devices. They believe that this technology has a direct advantage for not simply pharmaceutical sectors however even for other sectors, like petroleum, where our sensors can be placed along underground pipes to monitor the hydrocarbons’ compositions.
The study was contributed by Dr. Gerard Coté, Dr. Kristen Maitland, Cyril Soliman, Paul Gordon, Dandan Tu, and from the Department of Biomedical Engineering, and Megan Makela from the Department of Materials Science and Engineering.
Scientists downsize device used for Raman spectroscopy
Author: Sruthi S
