DNA combined with three-dimensional nanostructures created by DNA-origami or with DNA “bricks” can be used as markers when studying complex cellular behavior. The barcodes are comprised of sub-micrometer structures ranging in size from 50nm to 800nm created from self-assembling DNA strands. Previous fluorescent barcodes ranged in size from two to 100 micrometers in length, limiting the number of barcodes that can be used in a single sample. Once sequenced, the strands fold into sub-micro structures based on the principle of DNA self-assembly where A bases bind with T bases and C bases bind with G bases. The shape of the nanostructure is determined by the sequence of the strands, and they have a very stable and rigid geometry.
Fluorescent markers are attached to the DNA nanostructures at predetermined points to create optical markers visible through optical microscopy. Combinations of red, green, and blue fluorescents allow researchers to create numerous color and distance combinations on these rigid DNA nanostructures. The distance between the fluorescents and the combination of colors allow for tagging and potential in-situ imaging of cellular behavior. Additionally, the small size of the DNA barcodes allows for tagging of multiple molecular and cellular structures in a single sample, further increasing its usefulness. In the future, this technology may become part of an imaging library that can be used for molecular studies and biomedical diagnostics.
- Novel DNA Barcode Engineered: New Technology Could Launch Biomedical Imaging to Next Level. [Internet]. Submitted . Available from: http://www.sciencedaily.com/releases/2012/09/120924102458.htm
- . Submicrometre geometrically encoded fluorescent barcodes self-assembled from DNA. Nature Chemistry [Internet]. 2012 ;4(10):832 - 839. Available from: http://www.nature.com/doifinder/10.1038/nchem.1451
This technology is an enhancement over previous fluorescent molecular tagging technology in that it is smaller, and has an immensely larger potential library of identifying markers, all at a reduced cost and level of complexity.
This technology has the potential to be used in targeted drug delivery systems as well as in vivo imaging and imaging of cellular and molecular behavior at disease sites.
Like other synthesized strands of DNA, there is a risk that they can incorporate with living organisms if released into an uncontrolled environment. Although unlikely to self-replicate or hybridize in an uncontrolled environment, damage to DNA could be possible should the synthesized DNA incorporate with a living organisms DNA. Essentially, the DNA could cause genetic damage, but will not likely cause genetic mutation. This could pose potential human health and ecological risks as well as risks to the human condition.