Jan 30 2013
Researchers at Tokyo Institute of Technology produce new photoactive micelles with potential applications in photofunctional dyes and sensors.
A new form of micelle, which is composed of detergents with bent aromatic panels, has been created by Michito Yoshizawa and his colleagues at Tokyo Institute of Technology. Unlike traditional micelles, the new ‘aromatic micelles’ are photoactive, and capable of encapsulating dye molecules and showing unusual fluorescence in aqueous solutions.
“The present micelles might be suitable for potential applications in the fields of photofunctional dyes, sensors, and materials owing to their ability to accommodate dye molecules and their efficient host-guest energy transfer in aqueous media,” explain the researchers. They also emphasise the straightforward synthesis, aqueous green chemistry and high stability of the aromatic micelles.
Micelles are used in a range of dissolution, separation, and preservation applications and form the basis of soap detergents. They assemble from string-like molecules in aqueous solutions as a result of different chemical components (hydrophobic and hydrophilic moieties) at either end of the strings. Michito Yoshizawa and Kei Kondo et al. replaced the hydrophobic part of the string with large aromatic panels, which are known to be photochemically active.
The new aromatic micelles form two nanometer-sized capsules that have a cavity surrounded by large aromatic panels. The selective encapsulation of fluorescent dye molecules to form photoactive guest-host complexes is the first demonstration of efficient fluorescence energy transfer from the host framework to dye ‘guest molecules’.