RESUMEN
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 10â¯fgâ¯mL-1-10â¯ngâ¯mL-1 and the lowest detection limit of 1â¯fgâ¯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.
Asunto(s)
Aptámeros de Nucleótidos/química , Mediciones Luminiscentes/métodos , Nanopartículas/química , Zea mays/metabolismo , Zearalenona/análisis , 2,2'-Dipiridil/análogos & derivados , 2,2'-Dipiridil/química , Harina/análisis , Grafito/química , Límite de Detección , Compuestos Organometálicos/química , Puntos Cuánticos/química , Reproducibilidad de los Resultados , Dióxido de Silicio/química , Zea mays/químicaRESUMEN
In this work, the phenolic composition of four rare cultivars grown under the same agronomical and environmental conditions was studied. This is to test the effects of cultivars and ripening index essentially on phenolic composition in olive oils as well as tocopherols composition, organoleptic profiling and oxidative properties. Furthermore, some agronomical traits were determined in which a general increase in the size of the fruit and oil contents were recorded for all cultivars. The phenolic fractions were identified and quantified using liquid chromatography coupled to diode array detection and electrospray ionization tandem mass spectrometry (LC-DAD-ESI-MS/MS) in multiple reaction monitoring mode (MRM). A total of 13 phenolic compounds belonging to different chemical families were determined. Qualitative and quantitative differences in phenolic composition were observed among cultivars and also among sampling times. On the contrary to the agronomical traits, a general decrease (p<0.05) of total phenolic compounds was observed during maturation. Likewise, a decrease in tocopherols concentrations and oxidative properties was observed.