A nanometric sensor — an extremely small probe originally designed to test samples for the presence of herbicides, heavy metals, and pollutants — was experimentally shown to also detect molecules commonly associated with multiple sclerosis. Physicist Fábio de Lima Leite, a professor at the Federal University of São Carlos (UFSCar), Sorocaba, has been studying how this device may help diagnose diseases of the nervous system.
“We started by detecting herbicides and heavy metals,” described Dr. Leite, in a news article. “Now we’re testing the device for use in detecting target molecules typical of nervous system diseases, in partnership with colleagues at leading centers of research on demyelinating diseases of the central nervous system.”
The system was designed by Dr. Leite along with Alberto Luís Dario Moreau, who is a professor at the São Paulo Federal Institute of Education, Science & Technology (IFSP) in Brazil. “It’s a highly sensitive device,” said Dr. Leite. “We were able to increase sensitivity dramatically by going down to the nanometric scale.” The impressive technology was recently featured on the cover of IEEE Sensors Journal and described in the article, “A Nanobiosensor Based on 4-Hydroxyphenylpyruvate Dioxygenase Enzyme for Mesotrione Detection.”
Two main components give the system its functionality. The first is a nanoprobe made out of pure silicon or silicon nitride. On the tip of the nanoprobe is the second element, which can be any molecule such as an enzyme or other protein. When the molecule is brought in proximity to another molecule it binds to, the nanoprobe bends. The deflection is measured by the device, allowing the researcher using the device to identify a binding event.
Applying this technology to diagnosing multiple sclerosis or other related diseases such as neuromyelitis optica would require a patient sample, such as a drop of cerebrospinal fluid. Given the correct molecule is attached to the nanoprobe, the nanoprobe could indicate the presence of certain molecules in the patient’s sample. “If the interaction is low, we’ll be able to rule out multiple sclerosis with great confidence,” explained Dr. Leite. “High interaction will indicate that the person is very likely to have the disease.”
The device would not replace other means of detecting multiple sclerosis. A patient with a positive binding event would require additional testing such as MRI scans to rule out the possibility of a false positive diagnosis of multiple sclerosis. However, the device could help enhance the speed to diagnosis. “Even specialists experience difficulties or take a long time to diagnose [nervous system diseases],” stated Dr. Leite. “Our technique would provide a differential diagnostic tool.”
The group decided to pursue research in the area of nervous system diseases as another use for their device due to the difficulty encountered in the clinic to diagnose demyelinating diseases. While studying the use of the nanometric system to detect the presence of multiple sclerosis proteins, the team is also looking at its utility to detect biomarkers in other diseases such as head and neck cancers and chronic diseases. The group’s research into disease diagnosis is still in the early stages, but the team may be able to use this technology in animal studies and eventually clinical trials.