A new system developed at EPFL can detect and analyze molecules with very high precision and without needing bulky equipment. It opens the door to large-scale, image-based detection of materials aided by artificial intelligence.
The research has been published in Science.
Infrared spectroscopy is the benchmark method for detecting and analyzing organic compounds. But it requires complicated procedures and large, expensive instruments, making device miniaturization challenging and hindering its use for some industrial and medical applications and for data collection out in the field, such as for measuring pollutant concentrations. Furthermore, it is fundamentally limited by low sensitivities and therefore requires large sample amounts.
However, scientists at EPFL’s School of Engineering and at Australian National University (ANU) have developed a compact and sensitive nanophotonic system that can identify a molecule’s absorption characteristics without using conventional spectrometry. The scientists have already used their system to detect polymers, pesticides and organic compounds. What’s more, it is compatible with CMOS technology.
Their system consists of an engineered surface covered with hundreds of tiny sensors called metapixels, which can generate a distinct bar code for every molecule that the surface comes into contact with. These bar codes can be massively analyzed and classified using advanced pattern recognition and sorting technology such as artificial neural networks. This research – which sits at the crossroads of physics, nanotechnology and big data – has been published in Science.
Translating molecules into bar codes
The chemical bonds in organic molecules each have a specific orientation and vibrational mode. It influences the way molecules absorb light, giving each one a unique “signature.” Infrared spectroscopy detects whether a given molecule is present in a sample by seeing if the sample absorbs light rays at the molecule’s signature frequencies. However, such analyses require lab instruments with a hefty size and price tag.
The pioneering system developed by the EPFL scientists is both highly sensitive and capable of being miniaturized; it uses nanostructures that can trap light on the nanoscale and thereby provide very high detection levels for samples on the surface. “The molecules we want to detect are nanometric in scale, so bridging this size gap is an essential step,” says Hatice Altug, head of EPFL’s BioNanoPhotonic Systems Laboratory and a coauthor of the study.
The system’s nanostructures are grouped into what are called metapixels so that each one resonates at a different frequency. When a molecule comes into contact with the surface, the way the molecule absorbs light changes the behavior of all the metapixels it touches.
“Importantly, the metapixels are arranged in such a way that different vibrational frequencies are mapped to different areas on the surface,” says Andreas Tittl, lead author of the study.
This creates a pixelated map of light absorption that can be translated into a molecular bar code – all without using a spectrometer.
“Thanks to our sensors’ unique optical properties, we can generate bar codes even with broadband light sources and detectors,” says Aleksandrs Leitis, a coauthor of the study.
There are a number of potential applications for this new system. “For instance, it could be used to make portable medical testing devices that generate bar codes for each of the biomarkers found in a blood sample,” says Dragomir Neshev, another coauthor of the study.
Artificial intelligence could be used in conjunction with this new technology to create and process a whole library of molecular bar codes for compounds ranging from protein and DNA to pesticides and polymers. That would give researchers a new tool for quickly and accurately spotting miniscule amounts of compounds present in complex samples.
Receive an email update when we add a new NANOPHOTONICS article.
The Latest on: Detecting and analyzing organic compounds
via Google News
The Latest on: Detecting and analyzing organic compounds
- Lime Oil Market Analysis highlighting Opportunities and Development Status Finds Fact.MR on December 20, 2018 at 4:33 am
With a substantial consumer mass preferring natural and organic over conventional food ingredients ... Over 80% of the lime oil content is constituted by volatile compounds that predominantly account ... […]
- High Purity Metal Organics (HPMO) Market Size, Market Trends, Top Players, Growth, Analysis - Demand till 2023 on December 17, 2018 at 5:06 am
Dec 17, 2018 (Heraldkeeper via COMTEX) -- Market Overview: Metal organic compounds are the chemical compounds that ... the price constraint during the forecast period. Geographical Analysis: The major ... […]
- Rapid detection of foodborne pathogens on December 5, 2018 at 5:45 am
Development of a Volatile Organic Compound (VOC)-based detection system. Credit ... three winners for the Malaysian L'Oréal-UNESCO for Women in Science Award. VOCs analysis has been used in clinical d... […]
- Organics on Ceres may be more abundant than originally thought on June 13, 2018 at 10:13 am
scientists with NASA's Dawn mission announced the detection of organic material — carbon-based compounds that are necessary components for life — exposed in patches on the surface of the dwarf planet ... […]
- Organic molecules on Mars on June 7, 2018 at 11:52 am
The results convincingly show the long-awaited detection of organic compounds on Mars. As Webster et al. show, methane has also been conclusively detected in the martian atmosphere (3). During 5 years ... […]
- Stool-sample-sniffin' electronic nose detects diseases on December 27, 2017 at 11:51 am
Thanks to a new "electronic nose," however, it may soon be possible to detect ... between Crohn's and colitis – this is based on a three-minute analysis of the volatile organic compounds emanating fro... […]
- Sensors detect disease markers in breath on May 18, 2017 at 12:29 pm
Brian Stauffer A small, thin square of an organic plastic that can detect disease markers in breath or toxins in a building's air ... basically the size of a big table, to detect and analyze these com... […]
- Highly sensitive gas sensors for volatile organic compound detection on February 1, 2017 at 6:29 am
(Top) Schematic representation of the SnO2 nanorod sensor for volatile organic compound detection. (Bottom ... of different sizes and pore distribution patterns, and ran an analysis to determine optim... […]
- Journal of Pediatric Gastroenterology & Nutrition: on November 13, 2016 at 4:00 pm
However, microbiota analysis as early diagnostic biomarker is in clinical practice currently not feasible because of logistic aspects and high costs. Therefore, we hypothesized that analysis of fecal ... […]
via Bing News