|National Human Genome Research Institute via Wikimedia Commons|
The research team from Imperial College London developed a new method to quicken diagnosis of diseases by using a new nanopore transistor. This tiny transistor can detect protein molecules selectively at the single-molecule level. Detecting protein molecules at that level can provide help diagnosis of illness at early stages.
Usually, scientists look for rare and specific molecules within a complex mixture of body fluid samples and then use methods that detect single molecules at a time such as nanopore sensing technology. However, molecules with the same sizes may produce very similar signals that trouble scientists to find the unique molecule needed. This is the problem resolved by the research team by developing a new system based on two existing technologies - the nanoscale transistor and nanopore sensing. Similar to antibodies attaching to pathogens, receptors recognize molecules with specific shapes and attach to them like a lock-and-key mechanism known in enzymes and substrates.
In the study, researchers made the nanoscale transistor from a polymer material that can be imprinted with a lock or binding site. It enables the nanoscale transistor to detect the only possible key or target molecule to bind with. The team tested it to detect the antibody that binds to insulin, an important part to diagnose diabetes. According to the researchers, the design of the system may also be used on a broader range of biological molecules to detect specific molecules and help diagnose diseases.
Aside from the nanoscale transistor, an upgraded nanopore with an electrode attached to the polymer coating has been added to the system. It acts like a gate which manages the transport of molecules to the pore, preventing molecules from passing too quickly and evading detection.
“The complete system combines concentration, tuneable speed and selectively, which will be clinically relevant in the search for rare proteins such as specific kinds of antibodies and DNA molecules,” stated Professor Yuri Korchev of the Department of Medicine at the Imperial College London.