Novel Electrochemical Sensor Application for Dopamine and Preparation of N-rGO Micro-regionally Constrained WS₂ Nanocomposite

Abstract

Dopamine is an important neurotransmitter for organisms and affects their function, so monitoring and detecting dopamine levels is essential. Sensitivity and selectivity of electrochemical sensors for the detection of dopamine usually relies on hybrid nanocomposites. In this context, we designed a micro-regionally restricted hybrid nanocomposite by modulating the micro-nano structure. Using functional groups on nitrogen-doped reduced graphene oxide (N-rGO) to restrict the random growth of tungsten disulfide nanosheets, we obtained a 2D layered material with bidirectional structural support to achieve high specific surface and high activity for application in robust and novel dopamine electrochemical sensors. A facile electrochemical sensor for dopamine detection was fabricated by modifying a screen-printed carbon electrode with the nanocomposite. The sensor exhibits excellent performance of dopamine detection in the wide range of 1 µmol/L100 µmol/L with a detection limit of 0.2 µmol/L and a high sensitivity of 0.56 µA/µmol/L. The optimized sensor shows a good selectivity, satisfactory long-term stability and reproducibility towards DA and a separation of peak potential of 142 mV with uric acid. In addition, the prepared sensor provides favorable recovery in human serum and artificial cerebrospinal solution (aSCF), indicating great potentials in electrochemical detection and biological sensing applications.

Application of Molecularly Imprinted Electrochemical Sensor for Selective Non-Labelled Detection of Acetamiprid Insecticide in Fruits

“…[56][57][58][59] Randle-Sevcik Eq. 5 correlating, the slope of the relation between square root of the scan rate (υ 0.5 mV/s 0.5 ) and anodic peak current (I a μA) for 2.5 mM FCN in 0.1 M KCl solution was used for calculating the total surface area of the final sensor 60,61 Where: υ 1/2 is square root of the scan rate by mV/s 0.5 , C 0 is the concentration of the probe (2.5 mM), D 0 is the diffusion coefficient for FCN = 7.6 × 10 −6 cm 2 s −1 , A is the surface area of the electrode by cm 2 , and n is the number of transferred electrons for 1 mM FCN (n = 1). From Fig.…”