Scientists brew tree-shaped DNA

Researchers from Cornell University have synthesized a new type of DNA that can be used as a nanotechnology building block.

DNA, whether biological or artificial, consists of a series of nucleotide bases attached to a sugar-phosphate backbone. DNA usually comes in straight strands; these pair up and twist to form the familiar biological double helix.

The Cornell researchers have found a way to make branched, or Y-shaped DNA, and have constructed dendrimer, or tree-shaped, DNA by connecting branched DNA.

DNA shows great promise as a nanotechnology construction tool. It is water-soluble, non-toxic and biodegradable, can be manipulated using enzymes, and segments of DNA can be programmed to connect to other segments to self-assemble structures at the scale of molecules. The Y-shaped DNA is an additional tool for this effort, according to the researchers.

The DNA could eventually be used for nanoscale construction, drug delivery and molecular sensing, according to the researchers.

Practical applications will be possible in 5 to 10 years, according to the researchers. The work appeared in the December 21, 2003 issue of Nature Materials.