A New Approach to Hierarchical Self-Assembly

National Nanomanufacturing Network: Chemists from the University of Massachusetts Amherst, with Material Scientists from Duke, report a new approach to forming complex nanoparticle superstructures. The research was published in the February 19 issue of Nature.

Vince Rotello, Ben Yellen, and colleagues describe the self-assembly of colloidal nanoparticles in ferrofluid using controlled magnetostatic interactions. An applied magnetic field triggers the directed assembly process. One significance of this approach is its ability to align diverse colloidal particles into hierarchical, symetrical, and reproducible superstructures with multipolar geometries. In this case, up to three differently-charged particle types assemble to create highly sophisticated structural configurations.

“With previous methods, you could usually get one thing to assemble, or you may get two, but we’ve been able to get three particles at one time to assemble in a hierarchical manner," stated Rotello in a news release issued yesterday by the University of Massachusetts. 

This novel approach will lead to a better understanding of self-assembly processes and to the creation of new materials with unique properties and applications. This research was supported in part by the Center for Hierarchical Manufacturing.

Erb R, Son HS, Samanta B, Rotello VM, and Yellen BB. 2009. Magnetic assembly of colloidal superstructures with multipole symmetry. Nature 457(7232):999-1002. 

UMass Amherst Press Release