Device: Researchers at Tel-Aviv University have developed a device—based entirely on nanowires—that can collect and separate specific proteins for analysis from blood or urine. The strategy relies on two sets of nanowires integrated into one chip. First, antibodies attached to a “forest” of upright silicon nanowires (or nanoposts) collect and concentrate proteins from a drop of patient sample, while unwanted cells and proteins are washed away. Then, the concentrated proteins are washed from the nanowire forest to a set of nanowire sensors, also covered in antibodies targeted to the protein of interest, which convert protein binding to an electrical signal.
Within about 10 minutes, the chip can detect proteins at a high concentration—about 0.4 micromolar. The device can also be rigged with two sets of antibodies, allowing the scientists to detect two proteins in one sample. In work published last month (August 2) in Nano Letters, the device’s creators demonstrate ...