Integration of High-Entropy Oxide with Nitrogen-Doped Graphene for the Ultrasensitive Electrochemiluminescence Detection of Trolox and Dopamine

Abstract

Developing luminol-dissolved O2 (luminol-DO) electrochemiluminescence (ECL) systems with high performance as well as excellent stability to enhance the low ECL efficiency of DO is highly desired for real applications. Here, we prepared a composite of high-entropy oxide (HEO) and nitrogen-doped graphene (HEO/N-G), with well-defined abundant oxygen vacancies, and used it for performance-enhanced luminol-DO ECL sensing applications. Benefiting from its unique electronic structure, reactive oxygen species could be efficiently produced, followed by reaction with electrochemically generated luminol anion radicals to generate a much-enhanced signal of the resulting ECL system. The developed HEO/N-G-based luminol-DO ECL system was further successfully exploited for the ultrasensitive detection of Trolox and dopamine in the linear ranges of 1 nM to 25 μM and 100 pM to 10 nM, with detection limits of 1.0 and 0.00093 nM, respectively. The underlying ECL mechanism of the HEO/N-G luminol-DO ECL system was also discussed.

Fabrication of tin sulfide@functionalized carbon nanofiber composites for the electrochemical detection of the oxidative stress biomarker trolox

“…4 Despite this, excessive trolox (antioxidant-rich food) consumption can lead to major health problems such as blood clotting after injuries and serious hemorrhage, and it is also linked to hemorrhagic stroke, which is the body's natural defense. 5 Researchers confirmed in a variety of studies involving humans and animals that the effects of trolox are dosage dependent, with low levels acting as antioxidants and inhibiting toxicity. In contrast, high concentrations induce toxicity through oxidative stress.…”

“…According to the FAO/WHO Expert Committee on Food Additives (JECFA), the suggested daily intake of trolox should not exceed 0-1.4 mg kg À1 human body weight and 200 mg kg À1 food and beverages. [5][6][7] A number of such biomarkers in foodstuffs must be precisely determined to provide quick identification and accurate therapy. Therefore, developing comprehensive approaches to current techniques for determining trolox is important.…”

A Carbonate-Involved Amplification Strategy for Cathodic Electrochemiluminescence of Luminol Triggered by the Catalase-like CoO Nanorods

“…Until now, the luminol-dissolved O 2 (DO) electrochemiluminescence (ECL) system has been widely applied in sensing , and imaging, , benefiting from the good water solubility, non-toxicity, and cost-effectiveness of luminol. , The anodic ECL emission of luminol is always bright and obvious, due to the efficient reaction between the luminol anion radical produced during positive potential scanning and reactive oxygen species (ROS) at negative potential. , Compared with the anodic luminol ECL emission, the ECL emission of luminol triggered by narrow negative potentials is more competitive, thanks to the easier reaction and low biological sample damage . Unfortunately, few efforts have been devoted to luminol cathodic ECL emission despite multi-potential luminescence features in the luminol ECL system.…”

“…Until now, the luminol-dissolved O 2 (DO) electrochemiluminescence (ECL) system has been widely applied in sensing 1,2 and imaging, 3,4 benefiting from the good water solubility, nontoxicity, and cost-effectiveness of luminol. 5,6 The anodic ECL emission of luminol is always bright and obvious, due to the efficient reaction between the luminol anion radical produced during positive potential scanning and reactive oxygen species (ROS) at negative potential.…”

Ultrafast Response and High Selectivity of Diethylamine Gas Sensors at Room Temperature Using MOF-Derived 1D CuO Nano-Ellipsoids

“…A portable and versatile DEA sensor, particularly one capable of detection at room temperature (RT), will be in high demand. In recent years, a variety of sensors have been established and introduced into the market. , Among them, chemiresistive gas sensors based on metal oxide semiconductor (MOS) resistance can change rapidly upon contact with guest molecules followed by gas adsorption and catalytic reaction with various MOS materials, such as ZnO, MoO 3 , CuO, NiO, In 2 O 3 , WO 3 , and Fe 2 O 3 with better selectivity, fast response, LOD, high efficiency, high sensitivity, and low consumption, play a significant role in household, laboratory, and industrial gas detection equipment. , Furthermore, the p-type MOS material can generate a hole accumulation layer that effectively adsorbs oxygen molecules, exhibiting excellent catalytic effects and being less affected by high temperatures and humidity. , Recently, CuO, a p-type semiconductor, has been regarded as the most promising material for sensing. It can absorb a significant number of oxygen molecules due to cation/anion vacancies, a narrow bandgap (1.24 eV), outstanding thermal conductivity, nontoxicity, redox-rich and catalytic performance, low cost, high electron mobility, and the capacity to detect gases at RT. − Moreover, numerous techniques have been used to incorporate cation/anion vacancies into metal oxide materials .…”