Advertisement

If you have an ACS member number, please enter it here so we can link this account to your membership. (optional)

ACS values your privacy. By submitting your information, you are gaining access to C&EN and subscribing to our weekly newsletter. We use the information you provide to make your reading experience better, and we will never sell your data to third party members.

ENJOY UNLIMITED ACCES TO C&EN

Materials

Nanopixels Of Any Color

Researchers assemble multicolor fluorescent nanostructures that might one day be used in miniaturized displays

by Lauren K. Wolf
March 10, 2014 | A version of this story appeared in Volume 92, Issue 10

This scheme shows a red cylindrical micelle on the left. To the ends of this micelle, researchers add red, green, and blue fluorescent copolymers in equal portions to add white segments onto the micelle. Then they add only red copolymers, yielding a red-white-red-white-red nanostructure.
Credit: Zac Hudson (SCHEME); NAT. COMMN. (MICROGRAPH)
Zachary M. Hudson, Manners’s Canadian postdoc, made patriotic micelles by assembling red, green, and blue copolymer strands. An equal mix of these colors yields a white stripe, as shown in this fluorescence microscopy image.

Making nanomaterials that emit multiple colors of light in well-defined patterns isn’t easy. Fluorescent dyes laid out on a nanoscale object tend to be so close together that they transfer energy among themselves, giving off distorted hues. Still, researchers want to make precision nanoemitters for use in miniaturized displays and data storage devices. To that end, Ian Manners of the University of Bristol, in England; Mitchell A. Winnik of the University of Toronto; and coworkers have produced multicolor nanostructures from block copolymers (Nat. Commun. 2014, DOI: 10.1038/ncomms4372). When immersed in ethyl acetate solvent, one of the polymer blocks is crystalline, and the other block—containing a red, green, or blue dye—is fluid. As a result, these copolymers form so-called cylindrical micelles with 10-nm-wide solid cores and brushlike coronas. Because the dyes are located in the coronas, they don’t spend time close to one another, and energy transfer and color distortion are avoided, Manners says. The researchers can mix red, green, and blue copolymer strands in standard ratios to generate micelles of any color, including white. Once an assembly is complete, the team can create “pixels” of a new color by adding a different mix of strands to the cylinder’s reactive ends.

Article:

This article has been sent to the following recipient:

0 /1 FREE ARTICLES LEFT THIS MONTH Remaining
Chemistry matters. Join us to get the news you need.