A team at Harvard's Wyss Institute for Biologically Inspired Engineering, Harvard Medical School, and Dana-Farber Cancer Institute has created nanodevices made of DNA that self-assemble and can be programmed to move and change shape on demand--a discovery that could lead to nanoscale drug-delivery systems.
Built at the scale of one billionth of a meter, each device is made of a circular, single-stranded DNA molecule that, once it has been mixed together with many short pieces of complementary DNA, self-assembles into a predetermined 3D structure. Double helices fold up into larger, rigid linear struts that connect by intervening single-stranded DNA. These single strands of DNA pull the struts up into a 3D form. The structure's strength and stability result from the way it distributes and balances the counteracting forces of tension and compression.
"This new self-assembly based nanofabrication technology could lead to nanoscale medical devices and drug delivery systems, such as virus mimics that introduce drugs directly into diseased cells," says co-investigator and Wyss Institute director Don Ingber in a statement. A nanodevice that can spring open in response to a chemical or mechanical signal could ensure that drugs not only arrive at the intended target but are also released when and where desired.
"These little Swiss Army knives can help us make all kinds of things that could be useful for advanced drug delivery and regenerative medicine," adds lead investigator William Shih. "We also have a handy biological DNA Xerox machine that nature evolved for us," making these devices easy to manufacture.
Their work appears in the June 20 advance online issue of Nature Nanotechnology.
- see the Wyss Institute's press release
- click here to access the study (sub. req.)