Semiconductor Device-Based Sensors for Gas, Chemical, and Biomedical Applications

260 Semiconductor Device-Based Sensors for Gas, Chemical, and Biomedical Applications

© 2011 by Taylor & Francis Group, LLC

6.4.8  slow resPonse due to diffusion

With the advent of nanowire sensors, the rst efforts were made to determine how the slow diffu-

sion of the relatively large biomolecules limits the ultimate practical sensitivity that can be obtained

in solution if the response is limited by diffusion [160]. For the lower concentrations being inves-

tigated, the question arises: What is the density of conjugated molecules on the sensor surface if

one waits a practical time to record the change in signal if targets are simply allowed ...