Macromolecules shape up

Engineered, shaped molecules to act as designer devices.

Chemists at the University of Pittsburgh, US, have added to their growing collection of molecular building blocks with a unique U-shaped molecule. The unit has been specifically designed to form a sharp turn and is the latest addition to a series that already contains rods and other turns.

Christian Schafmeister, assistant professor of organic chemistry, is designing building blocks for a universal system that will allow others to engineer and rapidly construct macromolecules for specific purposes. The molecules could be used to engineer a wide range of devices, from catalysts to molecular switches.

This latest monomer, named hin(2S4R7R9R), forms a tight turn that will be useful when trying to construct compact 3D structures, says Schafmeister. The molecule links in the same manner as for other units in the series through a pair of amide bonds, using standard solid-phase coupling techniques. Complex macromolecules can then be formed by step-by-step addition of units in sequence to produce the required overall shape and function.

The systematic, modular approach could help chemists piece together units to create perfect fits for biomimetic and nanotechnology applications with well defined geometries. Computer modelling played a large part in the molecular design. Schafmeister and colleagues are now working towards a program to help design the best molecular shape for a given application, which will let the software decide the best way to achieve this.

Schafmeister has received several awards in recent years for his innovative approach to macromolecule construction, and earlier this year was presented with the National Science Foundation Faculty Early Career Development Award for work in this area.

Vikki Allen