We have developed a new class of ultrathin porous nanocrystalline silicon (pnc-Si) membranes using inexpensive and scalable silicon fabrication techniques. Pnc-Si is formed from a deposited amorphous silicon thin film, where nanoscale pores are introduced through a thermodynamically-driven crystallization process developed by our group. Our robust 15nm thick membranes are free standing over hundreds of microns and can support >1 atm of differential pressure using only the surrounding silicon wafer framework as external support. The pore size and porosity are tunable and ideal for biomolecule separations. We demonstrate that pnc-Si membranes can retain proteins while permitting the transport of small molecules at rates an order of magnitude faster than existing materials (156 nmol/cm2-hr). Furthermore, we demonstrate that our membrane can effectively separate differently sized proteins. We have also shown fractionation of protein extract containing dozens of differently sized proteins at concentrations as high as 9mg/mL. Future integration of our novel nanomaterial into microfluidic systems will enable the development of rapid and high-efficiency blood analyzers and hemodialysis devices.
Journal: TechConnect Briefs
Volume: 4, Technical Proceedings of the 2007 NSTI Nanotechnology Conference and Trade Show, Volume 4
Published: May 20, 2007
Pages: 582 - 585
Industry sector: Advanced Materials & Manufacturing
Topicss: Advanced Manufacturing, Nanoelectronics