A skeleton-like synthetic material made from silicon has been created using a chemical process by scientists that could have potential uses in medical devices.
A group of researchers from Chicago University and Northwestern have developed a semiconducting silicon structure using bone formation as a guide. The synthetic material has the potential for improving interaction between soft tissue and hard materials.
Joe Akkara, a program director in the National Science Foundation materials research division, said: “This is the power of basic scientific research. The group has created a material that preliminarily seems to enhance soft tissue function.”
The researchers, led by Bozhi Tian, said they devised a new method for the syntheses and fabrication of mesocopic three-dimensional semiconductors - an intermediate between the nanometer and macroscopic scales.
“This opens up a new opportunity for building electronics for enhanced sensing and stimulation at bio-interfaces,” said lead author Zhiqiang Luo, a postdoctoral scholar in Tian's laboratory.
Tian's 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 3D semiconductors,” said co-lead author Yuanwen Jiang.
The testing showed that the synthetic silicon structures displayed stronger interactions with collagen fibres – a skin-like stand-in for biological tissue – than the currently available silicon structures. The team inserted the synthetic spicules and the other silicon structures into the collagen fibres, then pulled them out.
“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,” Tian said.
The spicules show promise for clearing this hurdle. They penetrated easily into the collagen and became deeply rooted, much like a bee stinger in human skin.