Potsdam, NY--Igor Sokolov and his team at Clarkson University have discovered a method of synthesizing the brightest-yet fluorescent-silica nanoparticles.1 The mesoporous nanoparticles have potential applications in medicine, biology, materials science, and environmental protection, among others.
Sokolov's process physically entraps a large number of organic fluorescent molecules inside nanoporous silica particles, which can be 20 to 50 nm in diameter, while preventing the molecules from leaking out. As an example of their brightness, the fluorescence of 40 nm particles is 34 times brighter than the brightest water-dispersible (25 to 30 nm) quantum dots and seem to be the brightest nanoparticles created so far.
In 2007, Sokolov and his team discovered a method of making the brightest ever synthesized fluorescent silica micro (not nano) particles. Various attempts to decrease the size of the particles to the nanoscale led to particles that were bright but not ultrabright; the problem was in the dye leakage. It took the group several years to finally synthesize the ultrabright nanoparticles.
"The particles should have a significant impact in the biomedical area," says Sokolov. "The particles are much more stable against photo-beaching than typical fluorescent dye. This means that one can trace the particles for a very long time."
1. Eun-Bum Cho et al., Small (2010) DOI: 10.1002/smll.201001337
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