An artificial skeleton-like material from silicon allows improved integration of medical implants into the body. Bozhi Tian, Assistant professor in chemistry at the University of Chicago, developed the first skeleton-like silicon spicules ever prepared via chemical processes.
"Using bone formation as a guide, the Tian group has developed a synthetic material from silicon that shows potential for improving interaction between soft tissue and hard materials," said Joe Akkara, a program director in the US National Science Foundation materials research division.
The team achieved many advances in the development of semiconductor and biological materials. One advance was the demonstration, by strictly chemical means, of three-dimensional lithography.
The team developed a pressure modulation synthesis, to promote the growth of silicon nanowires and to induce gold-based patterns in the silicon. Gold acts as silicon's growth catalyst.
By repeatedly increasing and decreasing the pressure on their samples, the researchers were able to control the gold's precipitation and diffusion along the silicon's faceted surfaces.
"The idea of utilizing deposition-diffusion cycles can be applied to synthesizing more complex 3-D semiconductors," said co-lead author Yuanwen Jiang, a Seymour Goodman Fellow in chemistry at University of Chicago.
The synthetic silicon spicules displayed stronger interactions with collagen fibers - a skin-like stand-in for biological tissue - than did currently available silicon structures.
"One of the major hurdles in the area of bioelectronics or implants is that the interface between the electronic device and the tissue or organ is not robust. The spicules show promise for clearing this hurdle. They penetrated easily into the collagen, then became deeply rooted, much like a bee stinger in human skin, " said Tian.