By Sometimes science fiction does inspire science research. À la Jurassic Park’s entombed mosquito, scientists have developed a method to store DNA in an amberlike material and still extract it easily hours later. This storage method is cheaper and faster than existing options, the researchers report in the June Journal of the American Chemical Society.
If you want to store information for a very long time, possibly forever, DNA is the way to do it, says James Banal, a chemist at MIT and technical director of a biotechnology company called Cache DNA, headquartered in San Carlos, Calif. DNA stores the genetic information of millions of organisms, but it can potentially be used to store any kind of information, including digital data such as text, photos, videos and more (SN: 10/2/19).
DNA’s storage density is many orders of magnitude higher than that of any device humans have created. For example, if every movie ever made was encoded in DNA, it would fit inside the volume of a sugar cube with room to spare. But DNA is also incredibly fragile and needs careful handling and storage. Existing storage methods require freezing temperatures, specialized equipment or hazardous chemicals such as hydrofluoric acid. Researchers have tried storing DNA at room temperature in silica and other materials, without success.
Banal and colleagues’ new method, called Thermoset-REinforced Xeropreservation (T-REX), encapsulates DNA in glassy polymer networks at room temperature. Using a combination of lock-and-key chemicals that “open up” the polymer’s structure, the researchers can retrieve the DNA. The material is similar to polystyrene plastic, picked by the team because it isn’t easily broken down by nature: Anything encapsulated in plastic can endure for a very long time. But the team made a tiny yet important addition to the plastic — a chemical weakness in the form of a molecule called thionolactone. “That allows us to deconstruct the polymer to get the information back,” Banal says.
To test the resilience of the polymer, the researchers encapsulated strands of DNA containing the encoded Jurassic Park theme music and a human’s entire genetic instruction book in the amberlike material and then exposed it to temperatures of 55° Celsius, 65° C and 75° C at 70 percent humidity over seven days. The team used benign reagents, rather than hydrofluoric acid, to extract the stored DNA, then used DNA-reading techniques to retrieve the stored information, all in a matter of hours — not the days needed to do this with silica-based materials.
Once extracted, the DNA can even be re-encapsulated using the same material, in “a circular kind of chemistry that is actually very beautiful,” Banal says.
The T-REX method appears to be more efficient than existing methods to store DNA at room temperature, says Dina Zielinski, a computational biologist at Whitelab Genomics, a company in Paris focused on creating digital tools to accelerate drug development. “So even though one could argue that the improvements are incremental [compared with silica methods], they do bring us closer to practically being able to store nucleic acid for hundreds, even thousands, of years at room temperature, which has broad-reaching impact.”
Banal and colleagues are working on making the method simpler so that it can one day be used in the field to collect and preserve genetic data or other specimens, like seeds or proteins, in remote locations — or even used to transport biological molecules for space research.
