Highly Sensitive and Selective Electrochemical Detection of Dopamine and Uric Acid Using Sea Urchin-like Tungsten Oxide Nanostructure Modified SPCE

Abstract

Here, screen-printed carbon electrodes (SPCEs) were modified with ultrafine and mainly monodisperse sea urchin-like tungsten oxide (SUWO3) nanostructures synthesized by a simple one-pot hydrothermal method for highly sensitive and selective detection of dopamine (DA) and uric acid (UA). Sea urchin-like nanostructures were clearly observed in scanning electron microscope images and WO3 composition was confirmed with XRD, FTIR and UV-Vis spectrophotometer. Modification SPCEs with SUWO3 nanostructures via the drop-casting method clearly reduced the R𝑐𝑡 value of the electrodes, lowered the ΔEp and enhanced the DA oxidation current due to high electrocatalytic activity. As a result, SUWO3/SPCEs enabled highly sensitive detection of DA (LOD: 51.4 nM and sensitivity: 127 μAmM−1cm−2) and UA (LOD: 253 nM and sensitivity: 55.9 μAmM−1cm−2) at low concentration. Lastly, SUWO3/SPCEs were tested with artificial urine, in which acceptable recoveries for both molecules were obtained. Given the high selectivity, the sensor has the potential to be used for highly sensitive simultaneous detection of DA and UA in real biological samples