Researchers at Delft University of Technology have demonstrated for the first time that nano-antennas can enhance the fluorescence of proteins in living human and other mammalian cells. Scientists already use smart fluorescent proteins that light up when the electrical voltage across a nerve cell changes. By placing nano-antennas close to these light-emitting proteins, researchers can monitor processes inside cells with much greater precision. The discovery adds a new tool for revealing electrical signals in the brain through nanotechnology as well as genetic engineering. The research has been published in Advanced Materials.

Monitoring signals in the brain requires both high resolution and rapid imaging. “Existing methods for visualizing voltage changes in cells often do not produce enough light, or they do not respond quickly or strongly enough to the small electrical pulses that occur at synapses,” says principal investigator Daan Brinks.

First authors Marco Locarno and Qiangrui Dong achieved a breakthrough by placing nano-antennas extremely close to fluorescent voltage-sensitive proteins. This made the proteins up to six times brighter, allowing researchers to monitor processes in living mammalian cells with much greater precision. Importantly, the cells remained alive and continued to function normally throughout the measurements.