A review on graphene-based electrochemical sensor for mycotoxins detection.

Fabrication strategies and surface tuning of hierarchical gold nanostructures for electrochemical detection and removal of toxic pollutants.

Because trace amounts of nitrite would cause adverse effects on human health, the development of low-cost, portable, and easy-to-use tools is very significant for tracking and evaluating nitrite contamination in water. Herein, we described a smartphone-based electrochemical system for rapid quantification and mapping of nitrite contamination. The system contained a smartphone, a hand-held detector, and a modified screen-printed carbon electrode (SPCE). With a home-made Android application, the smartphone was used to control the detector, display the detection results, and link the system to the Cloud. The hand-held detector (∼42 g) was designed to apply the excitation signals on the modified SPCE and transmit the response data to the smartphone via Bluetooth. The SPCE was used as a sensor for nitrite sensing, on which gold nanoparticles, NiO nanoparticles, and reduced graphene oxide were in-situ electrochemically deposited by the system. The smartphone-based system showed excellent analytical performance for the detection of nitrite with a low detection limit of 0.2 μM in a linear range of 1-500 μM. Furthermore, a nitrite contamination map was constructed by measuring the water samples at different locations in Hainan Province, thus showing great potential of this system for water quality monitoring, especially in low-resource countries.

Cost-effective, wireless, and portable smartphone-based electrochemical system for on-site monitoring and spatial mapping of the nitrite contamination in water

Synergistic integration of Au nanoparticles, Co-MOF and MWCNT as biosensors for sensitive detection of low-concentration nitrite

The accurate and precise monitoring of epirubicin (EPR), one of the most widely used anticancer drugs, is significant for human and environmental health. In this context, we developed a highly sensitive electrochemical electrode for EPR detection based on nickel ferrite decorated with gold nanoparticles (Au@NiFe2O4) on the screen-printed electrode (SPE). Various spectral characteristic methods such as Fourier transform infrared spectra (FT-IR), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), ultraviolet-visible spectroscopy (UV-Vis), energy-dispersive X-ray spectroscopy (EDX) and electrochemical impedance spectroscopy (EIS) were used to investigate the surface morphology and structure of the synthesized Au@NiFe2O4 nanocomposite. The novel decorated electrode exhibited a high electrocatalytic activity toward the electrooxidation of EPR, and a nanomolar limit of detection (5.3 nM) was estimated using differential pulse voltammetry (DPV) with linear concentration ranges from 0.01 to 0.7 and 0.7 to 3.6 µM. The stability, selectivity, repeatability reproducibility and reusability, with a very low electrode response detection limit, make it very appropriate for determining trace amounts of EPR in pharmaceutical and clinical preparations.

Fangqin Cheng

Papers

Sensitive electrochemical sensor for nitrite ions based on rose-like AuNPs/MoS2/graphene composite.