Prototyping of wrinkled nano-/microstructured electrodes for electrochemical DNA detection

Biosensing platforms are ideal for addressing the diagnostic needs of resource-poor areas; however, the translation of such systems from the laboratory to the point-of-need has been a slow process. Rapid prototyping methods that enable an application-specific biosensor to be created in a matter of hours from design to fabrication would expedite the clinical and field testing of such systems. Here, we demonstrate a benchtop method based on craft cutting and polymer-induced wrinkling for creating multiplexed electrochemical DNA biosensors. This fabrication method allows multiscale wrinkled electrodes with features in the millimeter to nanometer length scales to be created in a matter of hours. These wrinkled electrodes display an enhanced surface area compared to planar electrodes and are shown to be structurally tunable by changing the film thickness. We demonstrate that structural tunability of these electrodes is translatable to functional tunability as the density of surface-immobilized probe molecules can be manipulated using wrinkled electrodes of different thicknesses. Furthermore, a simple proof-of-concept electrocatalytic DNA biosensor is demonstrated for distinguishing between complementary and noncomplementary oligonucleotides.