Here I recommend you a wonderful bio-app, named: caDNAno. The open-source software, caDNAno, will enables you design three-dimensional
DNA origami nanostructures. You can fold your DNA in any shapes. One of the features is no programming required, thus even our kids can give it a try, and perhaps can get a Science paper published .
What will DNA origami do?
Drug loaded and kill cancer cells. DNA is known to carry the genetic information, but here DNA changes its faces. No more genetic codes. Since the four basic bricks of DNA, A, T, G and C, will bind in pairs (A-T, G-C) according to Watson-Crick base paring principles, scientists could use the principle and engineer the DNA self-assembly to get designed 3-D structures, for example, a medicine capsule.
How does DNA robot work?
First we need drug loaded. When DNA is designed to a box with the help of caDNAno for example, it can be loaded with drugs, which is easy.
Second part, killing target without fault, is tough and tricky, just as quoted from the author.
Whether or not these structures will work in a living organism remains to be seen. For one thing, they are designed to communicate with molecules on a cell’s surface. “If your therapeutic target is inside the cell, it’s going to be tricky,” says Bachelet, a postdoctoral fellow at Harvard Medical School in Boston, Massachusetts, and one of the authors of the study .
One method to achieve target-killing, in my mind, is still to use the base paring principles. DNA nano-box per se is made up of four bases, thus a sequence can be designed as a switch to open or keep locking the nano-box.
Is it safe?
This is question is inevitable though I don’t want to expand. DNA nano-robot, is intrinsic DNA sequence, thus it is sensitive to DNase, enzyme to degrade DNA. Once DNA nano-robots are destroyed, which is quite easy, the payload will be leaked out to be harmful to nearby cells and tissues.
What can DNA nanotechnology do?
DNA nanotechnology can be applied to bio-computing and shows great promise. Qian, researches at California Institute of Technology, built up a bio-computing network based on DNA chain displacement. It is straightforward to watch the introduction video provided in the original paper .
DNA nanotechnology has a long way to go, nevertheless it shows promise in bio-computing and future therapeutics.
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 Douglas, S. M., Bachelet, I., & Church, G. M. (2012). A Logic-Gated Nanorobot for Targeted Transport of Molecular Payloads. Science, 335(6070), 831-834. doi:10.1126/science.1214081
 Qian, L., & Winfree, E. (2011). Scaling Up Digital Circuit Computation with DNA Strand Displacement Cascades. Science, 332(6034), 1196-1201. doi:10.1126/science.1200520