Researchers at University of California, Los Angeles (UCLA) have developed a tiny sensor that can help keep tabs on metabolites – substances produced or used when your body breaks down food, medication, or even its own fat and muscle in metabolic processes – far more extensively than current methods.
This tech could unlock new ways to detect and manage diseases and disorders, track patients’ responses to treatment, and accelerate the development of more effective drugs. What’s particularly interesting is how the sensor follows natural biochemical processes, like the way molecules are transformed and interact inside our bodies.
The team from UCLA’s California NanoSystems Institute calls its creations ‘tandem metabolic reaction-based sensors,’ or TMR sensors for short. They work like miniature chemistry labs work to monitor metabolites. The sensors are built onto tiny electrodes made of extremely small single-wall carbon nanotubes. The scientists put enzymes and helper molecules that aid in chemical reactions, called cofactors, on to these electrodes.
When a specific metabolite (the molecule they want to detect) comes near the sensor, the enzymes cause a chemical reaction. This reaction is very specific to the target metabolite. Sometimes, the sensor can detect the metabolite directly through this reaction. Other times, if the metabolite isn’t directly detectable, the enzymes will first convert it into another molecule that can be detected. This conversion can happen through a series of steps, like the natural metabolic pathways in the body. This ability to run multiple reactions is why they are called ‘tandem metabolic reaction-based sensors.’
A key part of these reactions is the exchange of electrons. When the enzymes act on the metabolite, they can cause electrons to move. These electron movements create an electrical current on the surface of the carbon nanotubes. The sensor then measures this electrical current. The amount of current tells the scientists how much of the metabolite is present. So, a higher current means more of the metabolite, and a lower current means less.
Essentially, the TMR sensors use nature’s own chemical reactions, happening on a tiny electrical surface, to turn the presence of metabolites into a measurable electrical signal.
Through a conversion step, these sensors can detect more than two-thirds of all the different metabolites produced in the human body. That could give us a detailed picture of what’s going on with a patient’s condition, and how they’re responding to a treatment.
The researchers note this technology could help detect heart disorders early and personalize treatments to tackle patients’ individual metabolic conditions. It could optimize athletes’ physical fitness by tracking how their bodies metabolize energy under stress. And TMR sensors could also shed light on how drugs in development influence metabolic pathways, and point to ways to optimize their effects.
Sam Emaminejad, a senior author on the paper that appeared in the Proceedings of the National Academy of Sciences journal last month, said this could help us understand the complex and mysterious connection between the gut and the brain.
“A major challenge in understanding how the gut and brain influence each other is capturing changes over time,” the scientist explained. “A tool that tracks metabolites continuously, rather than relying on single lab measurements, could help reveal this two-way communication. We’re finally equipped to test important hypotheses that lacked key data – helping us better understand how gut activity impacts overall health, from driving inflammation and affecting mental well-being to shaping chronic disease progression.”
Source: California NanoSystems Institute