April 2, 2023

MIT’s New Carbon Nanotube-Based Sensor Can Detect COVID-19 or Other Emerging Pathogens

The diagnostic is based on carbon nanotube sensing unit technology that Stranos lab has actually formerly established. Once the researchers started working on a Covid-19 sensing unit, it took them simply 10 days to recognize a modified carbon nanotube capable of selectively discovering the viral proteins they were looking for, and then check it and include it into a working model. A number of years ago, Stranos laboratory developed a novel technique to developing sensors for a variety of molecules. Within about 10 days of starting the project, the scientists had actually identified precise sensing units for both the nucleocapsid and the spike protein of the SARS-CoV-2 infection. During that time, they likewise were able to integrate the sensing units into a prototype gadget with a fiber optic tip that can discover fluorescence modifications of the biofluid sample in genuine time.

The diagnostic is based on carbon nanotube sensor technology that Stranos laboratory has previously established. As soon as the researchers began dealing with a Covid-19 sensing unit, it took them just 10 days to identify a modified carbon nanotube capable of selectively detecting the viral proteins they were looking for, and after that test it and include it into a working model. This method likewise eliminates the need for antibodies or other reagents that are lengthy to produce, purify, and make extensively available.
MIT postdoc Sooyeon Cho and college student Xiaojia Jin are the lead authors of the paper, which appears today (October 26, 2021) in the journal Analytical Chemistry. Other authors include MIT college students Sungyun Yang and Jianqiao Cui, and postdoc Xun Gong.
Molecular recognition
Numerous years earlier, Stranos lab developed an unique approach to developing sensors for a range of molecules. Their technique counts on carbon nanotubes– hollow, nanometer-thick cylinders made from carbon that naturally fluoresce when exposed to laser light. They have shown that by wrapping such tubes in various polymers, they can develop sensors that respond to particular target particles by chemically acknowledging them.
Their approach, referred to as Corona Phase Molecular Recognition (CoPhMoRe), benefits from a phenomenon that takes place when particular types of polymers bind to a nanoparticle. Understood as amphiphilic polymers, these molecules have hydrophobic areas that latch onto the tubes like anchors and hydrophilic areas that form a series of loops extending far from televisions.
Those loops form a layer called a corona surrounding the nanotube. Depending upon the plan of the loops, different types of target particles can wedge into the areas in between the loops, and this binding of the target alters the intensity or peak wavelength of fluorescence produced by the carbon nanotube.
Previously this year, Strano and InnoTech Precision Medicine, a Boston-based diagnostics developer, received a National Institutes of Health grant to produce a CoPhMoRe sensor for SARS-CoV-2 proteins. Scientists in Stranos lab had currently developed strategies that enable them to forecast which amphiphilic polymers will communicate finest with a particular target molecule, so they were able to rapidly generate a set of 11 strong candidates for SARS-CoV-2.
Within about 10 days of starting the task, the scientists had determined precise sensors for both the spike and the nucleocapsid protein of the SARS-CoV-2 infection. Throughout that time, they also had the ability to incorporate the sensors into a prototype gadget with a fiber optic tip that can detect fluorescence changes of the biofluid sample in real time. This removes the need to send the sample to a laboratory, which is needed for the gold-standard PCR diagnostic test for Covid-19.
This gadget produces a result within about five minutes, and can spot concentrations as low as 2.4 picograms of viral protein per milliliter of sample. In more current experiments done after this paper was sent, the scientists have actually achieved a limitation of detection lower than the quick tests that are now commercially readily available.
The researchers likewise revealed that the gadget might discover the SARS-CoV-2 nucleocapsid protein (however not the spike protein) when it was liquified in saliva. Identifying viral proteins in saliva is generally hard due to the fact that saliva consists of sticky carb and digestion enzyme molecules that disrupt protein detection, which is why most Covid-19 diagnostics require nasal swabs.
” This sensing unit reveals the highest variety of limitation of detection, action time, and saliva compatibility even without any antibody and receptor design,” Cho states. “It is a distinct feature of this kind of molecular acknowledgment scheme that quick style and testing is possible, unrestricted by the advancement time and supply chain requirements of a conventional antibody or enzymatic receptor.”
Quick response
The speed with which the scientists were able to develop a working model recommends that this technique could show beneficial for establishing diagnostics faster during future pandemics, Strano says.
“Were able to go from somebody handing us viral markers to a working fiber optic sensing unit in a very brief amount of time,” he states.
Sensing units that rely on antibodies to detect viral proteins, which form the basis of a number of the fast Covid-19 tests now offered, take much longer to develop since the process of creating the best protein antibody is so lengthy.
The researchers have declared a patent on the innovation in hopes that it might be commercialized for use as a Covid-19 diagnostic. Strano also wishes to further establish the innovation so that it might be deployed rapidly in action to future pandemics.
Reference: 26 October 2021, Analytical Chemistry.
The research study was funded by a National Institutes of Health Rapid Acceleration of Diagnostics (RADx) grant.

The scientists included their sensor into a model with a fiber optic idea that can spot changes in fluorescence in the test sample. Credit: MIT
The innovation could be developed as a fast diagnostic for Covid-19 or other emerging pathogens.
Using specialized carbon nanotubes, MIT engineers have designed a novel sensor that can discover SARS-CoV-2 without any antibodies, offering a result within minutes. Their brand-new sensing unit is based on technology that can quickly produce accurate and rapid diagnostics, not just for Covid-19 but for future pandemics, the researchers say.
” A quick test indicates that you can open up travel much previously in a future pandemic. “We do not yet have technology that can develop and release such sensing units quick enough to avoid financial loss.”