Developing a point-of-care real-time system for determination of dopamine, ascorbic acid, and uric acid using a modified screen-printed electrode in amicrofluidic chamber

A microcontroller based miniature potentiostat (MP) was developed based on Arduino Due and LMP91000EVM to act as a point of care health monitoring device for the first time. A designed syringe pump in tandem with a microfluidic chamber was successfully coupled with the MP to achieve a POC assembly. An SPE-3DG modified electrode was successfully interfaced with the potentiostat for simultaneous determination of UA, DA, and AA in human plasma samples. The voltage, waveform and scan rates were optimized for CV and DPV measurements.GA-PLS and WL-ANN were utilized to resolve overlapped peaks in contrast with time-consuming electrode surface modifications. The method showed better sensitivity in comparison with other methods. 3DG-SPE provides a broad accessible surface and shows remarkable increase in kinetic of electron transfer rate. In addition, it decreases the over potential for oxidation of analytes, which is desirable. Nonlinear methods such as ANN predict concentrations in the mixture slightly better than linear methods like PLS. In contrast, linear methods are simpler in algorithms and codes and also run faster on microprocessors, therefore both methods were performed. The developed miniature potentiostat is capable of detecting AA, DA, and UA at 0.95 uM, 0.12 uM, and 0.20 uM respectively with a linearity of 0.5-2000, 4-4500, 0.8-2500 uM with good determination coefficients . The results were in good agreement with other similar commercial instruments suggest that the developed device could be used as a real-time POC to monitor targeted analytes.