Electrochemistry on Paper-based Analytical Devices: A Review

Even though they were introduced less than a decade ago, electrochemical paper-based devices (ePADs) have attracted widespread attention because of their inherent advantages in many applications. ePADs combine the advantages of microfluidic paper-based devices (low cost, ease of use, equipment free pumping, etc.) for sample handling and processing with the advantages of sensitive and selective detection provided by electrochemistry. As a result, ePADs provide simplicity, portability, reproducibility, low cost and high selectivity and sensitivity for analytical measurements in a variety of applications ranging from clinical diagnostics to environmental sensing. Herein, recent advances in ePAD development and application are reviewed, focusing on electrode fabrication techniques and examples of applications specially focused on environmental monitoring, biological applications and clinical assays. Finally, a summary and prospective directions for ePAD research are also provided.