Simultaneous Electrochemical Detection of Uric Acid and Ascorbic Acid with Microfluidic Chips

Uric acid(UA)level in urine and blood serum can be used to diagnose several diseases such as gout.However conventional methods based on enzymatic reaction and colorimetric techniques require a long time and agreat amount of cost for other reagents. Electrochemical detection of uric acid with microfluidic chips was devel-oped:A PDMS microfluidic chip with a screen-printed electrode plate modified by carbon nano-tubes was fabricat-ed. With the chip,UA and ascorbic acid(AA)were detected using differential pulse voltammetry(DPV)method.The effect of UA and AA on the electrochemical responses was experimentally investigated and analyzed. The re-sults showed that:The oxidation peak current was proportional to the concentration of UA and AA over the detectionrange respectively. For simultaneous detection of UA and AA,two well-separated voltammetric peaks could be ob-tained in various levels of concentration. Both UA and AA had no significant effect on the position of voltammetricpeak,but restrained each other's peak currents.