The new sensor design resembles a molecular toolbox that can be used to quickly assemble sensors for different purposes. A collaborative research team from Bochum, Duisburg and Zurich has developed a new way to build a modular optical sensor to Bacteria and Viruses Detection with Fluorescent Nanotubes.
To accomplish this, researchers have used frimiously fluores and new types of DNA’s dunes like molecular. This anchoring technician can be used to combine the cost of information like anti-antibodies and nanotubes.
The account department can be joined in viruses or viruses and virus nanotubes. These associations apply to flourtoncence of nanotubes and more or lessen their light. A group consisting of Professor Sebastian Kruss, Justus Metternich and four colleagues from the Ruhr University in Bochum (Germany), Fraunhofer Institute for Microelectronic Circuits and Systems and ETH Zurich published their findings in the Journal of the American Chemical Society, published online June 27, 2023.
Simple Design of Carbon Nanotube Biosensors
The team used tubular carbon nanosensors with a diameter of less than one nanometer. When exposed to visible light, carbon nanotubes emit light in the near infrared. Near infrared light is invisible to the human eye. However, it is good for the eyes, since the level of other symptoms in this range is greatly reduced.
In previous studies, the team of Sebastian Kruss has already shown how the fluorescence of nanotubes can be changed to detect important biomolecules. Now, researchers have been looking for ways to easily design carbon sensors for different targets.
The key to success is a sequence of DNA defects called guanine quantum dots. This involves attaching DNA bases to the nanotube to create spots in the nanotube’s crystal structure. As a result, the fluorescence of the nanotubes changed at the quantum level.
In addition, the spot served as a molecular handle that allows the introduction of a detection domain, which can be adapted to a target molecule for the purpose of detecting a specific viral or bacterial protein. “With the insertion of the detector on the DNA anchor, the assembly of such a sensor is similar to the structure of the building – except that each part is 100,000 times larger than a human hair,” explains Sebastian Kruss.
The sensor detects various bacterial and viral targets
The team demonstrated the new sensor concept (Bacteria and Viruses Detection with Fluorescent Nanotubes) using the SARS CoV-2 spike protein as an example.
To achieve this, the researchers used aptamers, which bind to the SARS CoV-2 spike protein. “Aptamers are folded strands of DNA or RNA. Due to their structure, they can bind selectively to proteins,” explains Justus Metternich. “In the next step, one can transfer the concept to vaccines or other research fields.”
The fluorescent sensor showed the presence of the SARS-CoV-2 protein with high reliability. The selectivity of sensors with guanine quantum dots is higher than the selectivity of sensors without these defects. Additionally, the guanine quantum dot sensor is stable in solution.
“That’s an advantage if you’re considering size over just a water solution. For research applications, we need to check in complex environments, e.g. in cells, in the blood or in the organism itself, “says Sebastian Kruss, who heads the Functional Interfaces in Biosystems at Ruhr University Bochum and is a member of the Ruhr Explore Solvation Cluster of Excellence (RESOLV) at the International Graduate School of Neuroscience.
Source: Ruhr University in Bochum (Germany)
