'Zombie' replica cells may outperform live ones as catalysts and conductors

"Zombie" mammalian cells that may function better after they die have been created by researchers at Sandia National Laboratories and the University of New Mexico (UNM).

The simple technique coats a cell with a silica solution to form a near-perfect replica of its structure. The process may simplify a wide variety of commercial fabrication processes from the nano- to macroscale.

The work, reported in the Proceedings of the National Academy of Sciences (PNAS), uses the nanoscopic organelles and other tiny components of mammalian cells as fragile templates on which to deposit silica. The researchers then heat the cell to burn off its protein. The resultant hardened silica structures are faithful to the exterior and interior features of the formerly living cell, can survive greater pressures and temperatures than flesh ever could, and can perform some functions better than when they were alive, said lead researcher Bryan Kaehr, a Sandia materials scientist.

"It’s very challenging for researchers to build structures at the nanometer scale," said Kaehr. "We can make particles and wires, but 3-D arbitrary structures haven’t been achieved yet. With this technique, we don’t need to build those structures—nature does it for us. We only need to find cells that possess the machinery we want and copy it using our technique. And, using chemistry or surface patterning, we can program a group of cells to form whatever shape seems desirable."

UNM professor and Sandia Fellow Jeff Brinker added, “The process faithfully replicates features from the nanoscale to macroscale in a robust, three-dimensionally stable form that resists shrinkage even upon heating to over 500 degrees Centigrade [932 degrees Fahrenheit]. The refractoriness of these delicate structures is amazing.”