Glowing molecules shed light on biological processes
16 Aug 2012
Researchers have created fluorescent molecules that can be turned on and off to visualise activity within cells.
University of Miami researchers developed the molecules by strategically trapping them inside water-soluble particles and controlling them with ultraviolet light.
According to the team, the new system can be used to develop better fluorescent probes for biomedical research.
Previous studies have used water-soluble particles to bring organic molecules into water. What is novel about this system is the use of a photoswitching mechanism in combination with these particles.
“Finding a way to switch fluorescence inside cells is one of the main challenges in the development of fluorescent probes for bioimaging applications,” said researcher Francisco Raymo.
“Our fluorescent switches can be operated in water efficiently, offering the opportunity to image biological samples with resolution at the nanometer level.”
Fluorescent molecules are not water soluble; therefore Raymo and his team created their system by embedding fluorescent molecules in synthetic water-soluble nanoparticles called polymers that serve as transport vehicles into living cells.
Once inside the cell, the fluorescence of the molecules trapped within the nanoparticles can be turned on and off under optical control.
“The polymers can preserve the properties of the fluorescent molecules and at the same time assist the transfer of the molecules into water,” Raymo says.
“It’s a bit like having a fish in a bowl, so the fish can carry on with its activities in the bowl and the whole bowl can be transferred into a different environment.”
The new system claims to be faster and more stable than current methods.
The fluorescent molecules glow when exposed simultaneously to ultraviolet and visible light and revert back to their original non-luminous state in less than 10 microseconds after the ultraviolet light is removed.
