Ultrasensitive Detection of 2,4-Dinitrophenol Using Nanowire Biosensor

Figure 3

Time dependencies of the normalized differential signal from the SOI-NW sensor obtained upon DNP detection. DNP concentration 3 × 10⁻¹⁵ M (curve 1), 3 × 10⁻¹⁴ M (curve 2), and 3 × 10⁻¹³ M (curve 3) in deionized water. Inset displays examples of curves obtained in control experiments upon the addition of DNP-free solutions (ethanol or water) into the measuring cell. Experimental conditions: V_g = 20 V, V_ds = 0.2 V, and total solution volume in the cell 450 μL. Arrows indicate addition of DNP solution and washing with water.