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Semiconductor quantum dots (QDs) and tungsten disulfide nanosheets (WS

Accurate and early diagnosis of mycotoxin is particularly significant to the food and agricultural product safety. In the present work, a sensitive and effective monitoring method for zearalenone (ZEN) was exploited based on a novel self-enhanced electrochemiluminescence (ECL) aptasensor. The self-enhanced lumonophore was compounded by electrostatically combining amine-functionalized Ru(bpy)32+-doped silica nanoparticles (NH2-Ru@SiO2 NPs) and nitrogen doped graphene quantum dots (NGQDs) together. Since the emitter and co-reactant simultaneously existed in the same nanoparticle, shortened electron-transfer distance and decreased energy loss was obtained. Therefore, self-enhanced ECL aptasensor based on the novel complex expressed the widest linear range of 10 fg mL−1–10 ng mL−1 and the lowest detection limit of 1 fg mL−1 for ZEN detection. More importantly, ZEN produced during the mildew process of corn flour was monitored by the developed aptasensor, which exhibited superior determination and potential application in real samples.

Herein, an innovative ratiometric fluorescence (FL) aptasensor was successfully fabricated for the accurate analysis of zearalenone (ZEN) in corn and barley flour. The ZEN aptamer-modified nitrogen doped graphene quantum dots (NGQDs-apt) and silica sphere-encapsulated cadmium telluride quantum dots (CdTe QDs@SiO

Herein, an innovative ratiometric fluorescence (FL) aptasensor was successfully fabricated for the accurate analysis of zearalenone (ZEN) in corn and barley flour. The ZEN aptamer-modified nitrogen doped graphene quantum dots (NGQDs-apt) and silica sphere-encapsulated cadmium telluride quantum dots (CdTe QDs@SiO2) were directly mixed and applied as ratiometric probes. In the absence of ZEN, mitoxantrone (MTX), which was innovatively introduced as quencher, was captured by NGQDs-apt and its inner filter effect (IFE) on CdTe QDs@SiO2 was inhibited. When ZEN existed, MTX separated from NGQDs-apt and re-dispersed around CdTe QDs@SiO2 owing to the competitive binding of ZEN with its aptamer. As the IFE of free MTX on CdTe QDs@SiO2 recovering, the FL intensity of CdTe QDs@SiO2 was quenched, while the FL intensity of NGQDs-apt was nearly invariant. On this basis, a ratiometric FL aptasensor for ZEN was fabricated, which exhibited outstanding detection performances with a desirable detection limit of 0.32 pg mL−1.

Zearalenone (ZEN) is highly toxic to humans, and therefore, development of sensitive and effective methods for ZEN quantification in cereal crops is particularly important. Here, an innovative photoelectrochemical (PEC) aptasensor based on simply in-situ conjugated composites of zinc oxide-nitrogen doped graphene quantum dots (ZnO-NGQDs) was constructed. On addition of NGQDs, the composites displayed higher PEC signal with 8.8-fold enhancement than pure ZnO nanoparticles. A sensitive and selective PEC aptasensor was fabricated by combining the composites with ZEN aptamer, which yielded an excellent analytical performance for ZEN detection, with a wide linear range of 1.0 × 10−13–1.0 × 10−7 g mL−1 and a low detection limit of 3.3 × 10−14 g mL−1. Good recoveries were obtained using the PEC aptasensor, which were consistent with those obtained using the national standard method (HPLC-MS). Finally, ZEN in mildewing cereal crops was monitored with the PEC aptasensor, exhibiting good potential for application in cereal crops for early diagnosis.

Accurate and early diagnosis of mycotoxin is particularly significant to the food and agricultural product safety. In the present work, a sensitive and effective monitoring method for zearalenone (ZEN) was exploited based on a novel self-enhanced electrochemiluminescence (ECL) aptasensor. The self-enhanced lumonophore was compounded by electrostatically combining amine-functionalized Ru(bpy)