Design and Development of a PC-Based Analyte Detector Using Differential Pulse Voltammetry for Sensing Applications

This work presents a PC-based, DPV-exclusive potentiostat, termed the differential pulse analyte detector, optimized for electrochemical sensing. In contrast to conventional low-cost multifunctional potentiostats, the proposed system employs a DPV-specific design, which minimizes hardware overhead, reduces power consumption, and enhances measurement stability. The system is built around an ATmega16A microcontroller and an MCP4725 digital-to-analog converter, employing fully software-generated DPV waveforms without analog RC-based shaping circuits, thereby ensuring precise timing, enhanced waveform integrity, and long-term stability. A counter-electrode excitation strategy is implemented to maintain reference electrode stability and suppress capacitive background currents. The inclusion of a selectable transimpedance amplifier (1 kΩ–1 MΩ) provides a wide dynamic current range, while the ±2 V operating window exceeds that of several reported low-cost potentiostats such as ESPotensio and HunStat. The analytical performance of the device is validated using malathion as an analyte, achieving a sensitivity of 0.43 μA nM −1 and a limit of detection of 3.34 nM, comparable to a commercial CHI 660E workstation. An intuitive Visual Basic–based graphical user interface further enhances usability for non-expert users. Therefore, the differential pulse analyte detector is a cost-effective, DPV-optimized, field-deployable sensing platform with future expandability.