To solve the problem of dopamine deficiency, which is a characteristic of Parkinson's disease, is a key goal of new and old treatment methods, but monitoring the neurotransmitter level produced by these interventions may be a difficult task Scientists have developed a promising new tool for this task, which is described as a "fluorescent nano sensor coating", which emits light in the presence of dopamine to show its concentration and distribution in the brain
The decline in dopamine production seen in Parkinson's disease is associated with the development of motor symptoms such as tremor and poor balance. Although there is no complete cure for the disease, treatment can slow down the process and improve the quality of life of patients. These include levodopa, a drug that helps the brain produce more dopamine, and deep brain stimulation, which has been used for decades as a way to improve physical symptoms.
An accurate method of measuring dopamine will provide doctors with a powerful new method to monitor the effects of these treatments and let them improve their own methods to improve the treatment effects of patients. It is possible to use electrodes to measure chemical activity in the brain. In 2017, a team at the Massachusetts Institute of Technology (MIT) made a new array that can be used to monitor dopamine in the whole brain region in real time for a long time. In the following years, other electrode systems continuously improved the accuracy of this technology.
A research team led by scientists from Ruhr University in Bochum, Germany, has been pursuing another method. They hope to provide new spatial and temporal resolution for dopamine reading. The technology starts with ultra-thin carbon nanotubes that are about 10000 times thinner than human hair. Scientists have made some changes to give these tiny tubes new capabilities, and then enable them to bind to dopamine and emit more or less light according to its concentration.
Research team members Sebastian Kruss (right) and BJ ö RN Hill
"We have systematically modified this property by combining various short nucleic acid sequences with carbon nanotubes, which makes them change their fluorescence when they come into contact with certain molecules," said study author Sebastian Kruss. "We immediately realized that this kind of sensor is very interesting for neurobiology."
The scientists then tried to test the potential of the sensor in a functioning neural network, and they developed cell culture conditions for it in the laboratory. Applying a very fine layer of "fluorescent dopamine nano sensor coating" on nerve cells enables researchers to detect the secretion of neurotransmitters with high spatial and temporal resolution, which they say was impossible before. A specially established machine learning algorithm also enabled the sensor to reveal the dopamine release hot spots along the neuronal structure for the first time.
"They provide new insights into the plasticity and regulation of dopamine signaling. In the long run, they can also promote the treatment of diseases such as Parkinson's disease," said study author Sofia eizarova
The results of these early investigations suggest that this new sensor can be used as a tool to study the molecular and cellular mechanisms behind dopamine secretion. The scientists envision using the technology for other purposes, such as possibly adapting it to illuminate the signaling molecules that reveal pathogens.