Development of Pen‐type Portable Electrochemical Sensor Based on Au‐W Bimetallic Nanoparticles Decorated Graphene‐chitosan Nanocomposite Film for the Detection of Nitrite in Water, Milk and Fruit Juices

Abstract

The development and fabrication of a simple, portable, and sensitive detection tool to precisely monitor nitrite level is of growing importance in electrochemistry research, given the strong interest in the protection of drinking water quality, treatment of wastewater, food production, and control of remediation processes. This work describes the fabrication of a simple, cost‐effective, pen‐type electrochemical sensor based on bimetallic gold and tungsten nanoparticles electrochemically decorated on graphene‐chitosan modified pencil graphite electrode (PGE) for the trace detection of nitrite in real samples. The prepared nanocomposite was characterized using XRD, SEM, and EDS. The electrochemical behavior of the sensor was evaluated by cyclic voltammetry (CV) and impedance electrochemical spectroscopy (EIS). Results revealed that the proposed sensor displayed excellent electrocatalytic activity towards electro‐oxidation of nitrite with an irreversible redox reaction. The AuNPs‐WNPs@Gr‐Chi/PGE sensor exhibited excellent analytical performance with a wide linear range from 10 to 250 μM towards nitrite. The LOD and LOQ were calculated to be 0.12 μM and 0.44 μM, respectively. The designed electrochemical sensor was successfully applied for the detection of nitrite in water, milk, and natural fruit juice samples.

Noninvasive Electrochemical Nitric Oxide Detection in Human Saliva Using Pt and TiO2 Nanoparticle Composite Electrodes

“…The plots of ν 1/2 vs I pa follow a linear relation, confirming that the oxidation process is diffusion-controlled . The regression equations for ν 1/2 vs I pa plots have been obtained as follows The electrochemically active surface areas (ECSAs) of all above electrodes were estimated using the following Randles–Sevcik equation where the symbols I pa , , D , n , and C represent the peak current, electroactive area, diffusion coefficient, number of electrons transferred per scan rate, and concentration of the electrolyte, respectively. In the case of [Fe­(CN) 6 ] 3–/4– , n = 1 and D = 7.6 × 10 –6 cm 2 s –1 .…”

Highly sensitive capacitance-based nitrite sensing using polydopamine/AuNPs-modified screen-printed carbon electrode

“…The linear range obtained in this study was larger than that of other sensors based on gold nanoparticles 50 or composites of gold nanoparticles with polymers, 51,52 AuPs-decorated CNTs, 53 or a mixture of polymers and carbon nanomaterials. 53–55 Additionally, the designed electrode exhibited a relatively lower detection limit than that of glassy carbon electrodes (GCE) modified with gold nanoparticles 56 or with a mixture of gold nanoparticles with graphene. 57…”

Gold Nanomaterials and their Composites as Electrochemical Sensing Platforms for Nitrite Detection

“…A distinctive and advanced work was done for innovating a pen‐type electrochemical electrode, which was portable and highly recommended to apply in drinking water quality analysis wastewater treatment, food production, and remediation process monitoring.Lavanya and co‐workers [182] combined some components to design a sensor, which was effective for oxidation of nitrite. A fabrication of a potential cost‐effective sensor for the quantitative determination of nitrite based on Au−W bimetallic nanoparticles adorned graphene‐chitosan (Gr‐Chi) nanocomposites on pencil graphite lead was proposed in their study.…”