Study On Methods Based On Carbon Dots For Fast Detection Of Harmful Substances In Foods

In food,bisphenol A and histamine are ingested by the human body,it will produce many adverse reactions,and some may even endanger human health.In order to quantitatively detect and effectively control bisphenol A and histamine in food,it is urgent to develop a detection method with high sensitivity and strong selectivity.Traditional detection methods require complicated detection procedures,expensive equipment and complicated pre-processing,which limits their application.Therefore,it is of great significance to develop accurate,fast and highly sensitive detection method.In this paper,CDs-coated mesoporous fluorescence molecularly imprinted polymers was synthesized by sol-gel method,using BPAP as template molecule,carbon dots(CDs)as signal elements,and 3-aminopropyltriethoxysilane(APTES)as functional monomers,and a fluorescent molecularly imprinted sensor(CDs@MIP)was established to achieve the quantitative detection of bisphenol A.In the luminol-hydrogen peroxide system with histamine as the target,CDs as the catalyst,a flow injection analyzer was used to establish a flow injection chemical analysis method for histamine to achieve the quantitative analysis of histamine.(1)Research on the detection method of bisphenol A by molecularly imprinted fluorescence sensor based on carbon dotsMesoporous fluorescence molecularly imprinted polymers was synthesized by sol-gel method,using BPAP as template molecule,3-aminopropyltriethoxysilane(APTES)as functional monomers,tetraethyl silicate(TEOS)as crosslinking agent,cetyltrimethoxyammonium bromide(CTAB)as surfactant,carbon dots(CDs)as signal elements.The synthesized polymer was characterized by infrared,transmission electron microscopy,scanning electron microscopy,nitrogen adsorption and thermogravimetric analysis,and the morphology,then performance of the material were analyzed and studied.A mesoporous fluorescence sensor with high selectivity and sensitivity for the detection of bisphenol A has been established to perform fluorescence detection on food samples by using the fluorescence characteristics of CDs.The results show that the CDs@MIP mesoporous fluorescence sensor has a good linear relationship with bisphenol A,and has good repeatability and stability.Under optimal conditions,the linear range of this method was0.025 mg/L-2 mg/L,and the lowest detection limit(LOD)was 0.016 mg/L.In order to evaluate the accuracy of this method,the concentration of bisphenol A standard solution added in canned fish and orange juice was determined.The recovery rate of this method was92.5%-101.1%.Subsequently,the CDs@MIP sensor was used to determine the content of BPA in the food from canned hawthorn,yellow croaker,sardines and milk samples,and compared with the results determined by high performance liquid chromatography.Finally,the results show no significant difference with the results of high performance liquid chromatography.(2)Flow injection chemiluminescence detection method for histamine based on carbon dotsBased on the interaction of histamine on the luminol-hydrogen peroxide system,histamine used as the target,CDs used as catalytic,a flow injection chemiluminescence detection method based on carbon dots was established.Under the optimal conditions,this method had a good linear relationship with histamine concentration between 0.1 mg/L-40mg/L,and the lowest detection limit was 0.054 mg/L.The anti-interference of the flow injection chemiluminescence detection method of carbon dots for histamine was studied,and two liquor samples were added and recovered,the recovery rate of the two samples was97.0%-100.6%.Finally,the method was applied to the detection of histamine content in white vinegar,rice vinegar,and fish,and the results were in good agreement with the detection results of high performance liquid chromatography.The method has good stability and high sensitivity,and is suitable for the rapid detection of histamine in food.