Using carbon nanotubes to accurately detect dopamine neurotransmitter


The detection of neurotransmitters is important because these chemicals play a critical role in the communication between nerve cells in the brain and throughout the body. Neurotransmitters are released from one nerve cell, cross a small gap called the synapse, and bind to specific receptors on another nerve cell, which then triggers a response. By detecting neurotransmitters, scientists and researchers can gain insights into the mechanisms of the brain and nervous system, as well as the causes of various neurological and psychiatric disorders. For example, detecting changes in the levels or activity of neurotransmitters can help diagnose and monitor conditions such as depression, anxiety, Parkinson’s disease, and schizophrenia. Furthermore, understanding the role of neurotransmitters in normal brain function and behavior can help in the development of new treatments for these disorders. For example, drugs that target specific neurotransmitter systems can be used to treat depression or anxiety by regulating their levels or activity.

Carbon nanotubes (CNTs) are microscopic structures made of carbon atoms arranged in a cylindrical shape. They have unique mechanical, thermal, and electrical properties, and are used in a wide range of applications, from electronics to biomedical devices. The lifetime of carbon nanotubes can vary depending on their specific application and environment. In general, CNTs are known to be highly stable and can potentially last for decades or even centuries without degrading. However, their lifetime can be affected by various factors, such as exposure to heat, light, or chemicals, as well as mechanical stress or strain. For example, in biomedical applications, the long-term biocompatibility and degradation of CNTs are important considerations. Studies have shown that CNTs can persist in the body for extended periods of time, and their long-term effects on human health are still being studied. In electronic applications, CNTs can be used as components in transistors and other devices, but their stability and reliability over time are critical factors. Researchers are exploring ways to improve the performance and longevity of CNT-based electronics, such as by controlling the structure and purity of the nanotubes and optimizing their interfaces with other materials. Overall, the lifetime of carbon nanotubes is an important consideration in their various applications, and ongoing research is focused on improving their stability and performance over time. Indeed, carbon nanotubes not only shine brighter in the presence of dopamine, but also for longer. The time period of the shining serves as a new parameter to detect biological messenger substances.

In new research published in Angewandte Chemie International Edition, an interdisciplinary research team led by Professor Sebastian Kruss from Ruhr University found a new way to detect the neurotransmitter dopamine in the brain. The researchers used carbon nanotubes for this purpose. In earlier studies, the team had already shown that the tubes glow brighter in the presence of dopamine. Now the interdisciplinary group showed that the duration of the glow also changes. The authors used sensors composed of tubes made of carbon that are 100,000 times thinner than a human hair. When they are irradiated with visible light, they can even emit light in the near-infrared range, at a wavelength of 1,000 nanometers, which is not visible to humans. Previous studies by the authors had shown that certain carbon nanotubes modified with biopolymers glow brighter when they come into contact with certain biomolecules such as dopamine. In the new study, the researchers observed how long it takes for the nanotubes to emit this light in the near-infrared. To do this, the researchers observed the emitted light as individual light particles. Using a stopwatch, they recorded the time it took for the light particles to travel from the moment the nanotube was irradiated to the moment the light particles were released by the nanotube. This so-called lifetime of light is characteristic for different substances and represents a more robust signal compared to brightness. While the brightness depends on how many layers of cells the light has to pass through before it can be measured, this does not affect the lifetime of the light. Because each individual light particle carries the information about the lifetime, each measured particle is an increase in information, regardless of how many particles are measured.

Developing a new method for the detection of dopamine neurotransmitter is important for several reasons. Dopamine is a crucial neurotransmitter involved in many important functions such as movement control, motivation, reward, and mood regulation. An imbalance of dopamine levels is associated with various neurological and psychiatric disorders such as Parkinson’s disease, schizophrenia, depression, and addiction. Indeed, measuring the level of dopamine in biological fluids such as blood, urine, or cerebrospinal fluid can help diagnose and monitor several neurological and psychiatric disorders associated with dopamine imbalance. Moreover, a reliable and accurate method for measuring dopamine levels is essential for the development of drugs that can modulate dopamine activity in the brain. For example, drugs used for the treatment of Parkinson’s disease, such as L-DOPA, aim to increase dopamine levels in the brain. Furthermore, sudying the role of dopamine in the brain and its involvement in behavior, motivation, and reward processing requires accurate measurement of dopamine levels. Developing a method for detecting dopamine will facilitate neuroscience research and our understanding of the underlying mechanisms of brain function. The new method can assist in detecting dopamine levels can be used for personalized medicine to tailor treatment plans for patients with dopamine-related disorders. In conclusion, the author developed a reliable and accurate method for detecting dopamine neurotransmitter is essential for diagnosis, drug development, research, and precision medicine.

Using carbon nanotubes to accurately detect dopamine neurotransmitter - Medicine Innovates

About the author

Prof. Dr. Sebastian Kruss

Physical Chemistry II, Ruhr-University Bochum, Universitätsstr. 150, 44801 Bochum, Germany

Our research goal is to investigate and control complex chemical and biological systems by using and developing new methods and materials. Very often we make use of nanomaterials as building blocks to engineer functional materials. These materials are able to collect information or trigger processes from (bio)chemical systems and finally biological functions. Below you can find some examples of recently published work


Sistemich L, Galonska P, Stegemann J, Ackermann J, Kruss S. Near-Infrared Fluorescence Lifetime Imaging of Biomolecules with Carbon Nanotubes. Angew Chem Int Ed Engl. 2023 :e202300682. doi: 10.1002/anie.202300682.

Go To Angew Chem Int Ed Engl.