Storing DNA in an amber-like polymer, Jurassic Park–style

In the blockbuster film Jurassic Park, scientists resurrect dinosaurs by extracting DNA that’s been preserved in amber for millions of years. Inspired by such natural preservation, researchers have created glassy polymers that store DNA at room temperature and dissolve when needed to release the molecules (J. Am. Chem. Soc. 2024, DOI: 10.1021/jacs.4c01925). The method, dubbed thermoset-reinforced xeropreservation (T-REX), is a step toward low-cost data storage in DNA.

Computer memory devices process information as strings of zeros and ones. Those binary data could be encoded in the same four nucleotides—A, G, C, and T—that encrypt genetic information in DNA molecules. Scientists have proposed DNA as a data storage medium because it is dense: a coffee mug full of DNA could store all the world’s data.

But DNA decays in days at room temperature, so it is stored today at cryogenic temperatures, which requires energy and special equipment. “If I wanted to send DNA on a mission to Mars or collect samples in rural Africa, that’s not going to work,” says James Banal, cofounder of Cache DNA, which is developing a new biomolecule storage technology. For room-temperature storage, he and others have previously encapsulated DNA in silica particles and calcium phosphate crystals. This process takes days because water-loving DNA needs to be dissolved in organic solvents using surfactants, which are then removed via drying.

So he, Massachusetts Institute of Technology chemist Jeremiah A. Johnson, and colleagues devised a way to trap DNA in hours, using a hard polystyrene-based thermoset polymer. Thermosets, with their cross-linked polymer networks, are tough and resistant to chemicals. The researchers added small thionolactone sections to the network that can be cut with a cysteamine reagent.

The team made special polycation molecules composed of a water-loving side and an oily water-repellent one. Charges on the molecule bound to DNA and quickly transferred it from water to a solvent containing styrene monomers. Heating the solution created a glassy polymer block containing DNA. The material preserved DNA 10 times as long as silica particles could. Adding cysteamine disintegrated the polymer so the researchers could separate the DNA.

“This work could enable a more widespread application of DNA data storage, as encapsulation and extraction steps are simplified,” says Robert Grass, a chemist at the Swiss Federal Institute of Technology (ETH), Zurich, who was not involved in the current work. More in-depth analysis of the stability of DNA sequences will be needed to assess how the method stands up against current cryogenic techniques, he adds.