In focusing on the use of short strands of synthetic DNA and avoiding the long scaffold strand, Yin's team developed an alternative building method. Each SST is a single, short strand of DNA. One tile will interlock with another tile, if it has a complementary sequence of DNA. If there are no complementary matches, the blocks do not connect. In this way, a collection of tiles can assemble itself into specific, predetermined shapes through a series of interlocking local connections.
In demonstrating the method, the researchers created just over one hundred different designs, including Chinese characters, numbers, and fonts, using hundreds of tiles for a single structure of 100 nanometers (billionths of a meter) in size. The approach is simple, robust, and versatile.
As synthetically based materials, the SSTs could have some important applications in medicine. SSTs could organize themselves into drug-delivery machines that maintain their structural integrity until they reach specific cell targets, and because they are synthetic, can be made highly biocompatible.
"Use of DNA nanotechnology to create programmable nanodevices is an important focus at the Wyss Institute, because we believe so strongly in its potential to produce a paradigm-shifting approach to development of new diagnostics and therapeutics," said Wyss Founding Director, Donald Ingber, M.D., Ph.D.