Artigo Completo:

Silicon nanowires/nanoribbons (SiNW/SiNR) offer a highly sensitive and label free detection principle for biochemical applications, such as DNA and protein detection. The technique has potential both for low concentration detection as well as in scaling down the size of complete analysis systems required for rapid on-site applications. The sensor function is similar to that of a MOSFET transistor where the current passing from source to drain is dependent on the gate voltage. For SiNW/SiNR this current is dependent on the surface charges of the thin wire. When charged molecules are present at the surface, the conductance of the SiNW/SiNR is affected which is detected as a change in the drain current. Using localized functionalizion of individual SiNW/SiNR with antibodies and DNA probes and a multiplexed readout system, we can simultaneously detect different target molecules. We have demonstrated both DNA and protein detection using SiNW/SiNR. Combining the sensor system with a microfluidic delivery system, the sample volume can be minimized in order to take full advantage of the potentially very high detection sensitivity. The SiNW/SiNR are fabricated using standard CMOS technology which together with the label free electrical detection method enables mass production of fast, reproducible and low cost devices for disposable uses.