No one can code better than Mother Nature. So the idea of exploiting the structure of DNA to represent more complex information on a chip has long been a goal of researchers. Now a group of scientists believes it has an inexpensive nanoprinting technique that could lead to the mass production of DNA-based chips.
Led by Professor Francesco Stellacci of the Department of Materials Science and Engineering at the Massachusetts Institute of Technology, the research team calls its new DNA printing method "supramolecular nanostamping." The technique enables fragile single strands of DNA to assemble themselves on a surface to create a nanoscale duplicate of an original complex DNA pattern. The duplicate can then be used as a master to create additional copies of the DNA pattern.
"Our stamping technique has the advantage that it prints all DNA sequences at the same time, ultimately forming an information-rich pattern on a surface," explains Stellacci.
Such patterns are typically found today on DNA microarray chips, which are made up of hundreds of thousands of dots representing DNA molecules of known sequences. Those sequences are used to analyze a person's genetic code in order to predict the early onset of cancer or a couple's likelihood of having a child with a genetic disease.
Despite the potential of DNA microarrays, however, they are rarely used in medical diagnostics. One reason is that today a microarray requires over 400 printing steps. Stellacci's method requires just three printing steps, so it could bring the cost of such chips down from $500 to less than $50. At that price, routinely using the chips in many kinds of medical procedures and providing widely available genetic diagnostics would be feasible. Cost reductions would also carry over to lower costs for many kinds of procedures.
Stellacci doesn't expect to have a working prototype for at least a year. But he thinks that low-cost mass production of microarrays will make DNA analysis as commonplace as blood testing, which could lead to big advances in disease detection and more.