Fig. 3. A kanamycin-detecting electrochemical aptamer based (E-AB) sensor fabricated from wrinkled electrodes achieved a high signaling output. (A) As expected, we observed a monotonically increase of current (peak at −0.32 V) when spiking our sensors with increased target concentrations. The dotted line represents the voltammogram obtained from sensors in the absence of target. The subsequent voltammogram with increased current are collected from sensors spiked with a monotonical increase of target concentration (50 μM, 100 μM, 500 μM, 1 mM). (B) Prior to the addition of target, sensors fabricated on wrinkled electrode exhibit a 5-fold greater in absolute current for a given set of macroscopic dimensions (the size before shrunk: 70 mm × 70 mm, after shrunk: 14 mm × 14 mm). (C) The current difference between baseline (0 M target) and saturation (5 mM target), ΔI, is significantly enhanced by the use of wrinkled electrodes by 10-fold. (D) Sensors fabricated from either smooth or wrinkled electrodes respond rapidly to their target, reaching 90% of the total response within minutes (at, as shown here, 1 mM target), with wrinkled showing a slightly slower response probably due to slower diffusion onto the finely hierarchical structure. The error bars here and in the following figures represent the standard deviation of at least three independently fabricated sensors.