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

Surprise Route To Peptoid Nanosheets

Scientists find that peptoid-based materials form from compressed monolayers

by Stu Borman
October 17, 2011 | A version of this story appeared in Volume 89, Issue 42

[+]Enlarge
Credit: J. Am. Chem. Soc.
Amphiphilic peptoids (red is a hydrophilic surface, yellow is a hydrophobic surface) align at an air-water interface (top). Surface compression (dark gray blocks, middle) then induces nanosheet formation (bottom).
Nanosheet Formation -- Amphiphilic peptoids (red is hydrophilic, yellow is hydrophobic) form fibers that align in solution at the air-water interface (top). Mechanical pressure (dark gray blocks, middle) then induces nanosheet formation (bottom).
Credit: J. Am. Chem. Soc.
Amphiphilic peptoids (red is a hydrophilic surface, yellow is a hydrophobic surface) align at an air-water interface (top). Surface compression (dark gray blocks, middle) then induces nanosheet formation (bottom).

Nanosheets composed of amphiphilic peptoids (peptide analogs) assemble by an unexpected mechanism that may be applicable to other types of nanosheets. Peptoid nanosheets were first reported last year (C&EN, April 19, 2010, page 7). Their potential applications include sensing, templating, filtering, molecular recognition, and catalysis. Ronald N. Zuckermann and coworkers at Lawrence Berkeley National Laboratory’s Molecular Foundry, who developed the nanosheets, initially believed they form by a nucleation and growth mechanism in which small peptoid oligomers act as “seeds” for nanosheet assembly. They now find instead that amphiphilic peptoids align at the air-water interface to create monolayers, and that surface compression, which occurs when the vial is shaken, causes the monolayers to collapse into nanosheets (J. Am. Chem. Soc., DOI: 10.1021/ja206199d). In the nanosheet bilayer, hydrophilic groups are on the outer surface and hydrophobic groups are inside. Nanosheet formation is irreversible, so more than 95% of peptoids in solution can be converted. This preparative route may also be useful in making nanosheets from other building blocks, Zuckermann says.

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.