Nonfaradaic Current Suppression in DNA-Based Electrochemical Assays with a Differential Potentiostat.

摘要: One of the key factors limiting sensitivity in many electrochemical assays is nonfaradaic or capacitive current. This particularly true modern assay systems based on DNA monolayers at gold electrode surfaces, which have shown great promise for bioanalysis complex milieu such as whole blood serum. While various changes analytical parameters, redox reporter molecules, structures, probe coverage, and surface area been useful, background reduction by hardware subtraction has not yet explored these assays. Here, we introduce new electrochemistry that considerably suppresses currents through real-time analog during current-to-voltage conversion potentiostat. differential potentiostat (DiffStat) configuration to suppress remove capacitance chronoamperometry, cyclic voltammetry, square-wave voltammetry measurements applied nucleic acid hybridization surface. The DiffStat makes larger electrodes higher settings accessible user, providing order-of-magnitude improvements sensitivity, it also significantly simplifies data processing extract faradaic (SWV). Because two working are used measurements, unique arrangements introduced converting signal-OFF signal-ON drift correction 50% human Overall, this design should be helpful only improving most assays, but better support adaptation point-of-care circumventing processing.