Research On Qualitative And Quantitative Detection Of Uranyl Based On Fluorescence-SERS Dual-mode Probe

Uranium is the main raw material for nuclear energy.From the exploitation and utilization of uranium to the treatment of spent fuel,highly toxic uranium-containing pollutants will be produced.The radioactivity of uranium will lead to genetic mutations and cancer.In addition to radioactive damage,it will also cause permanent damage in tissues such as kidneys,livers,and bones.Therefore,it is of great significance for the detection of uranium.At present,the commonly used detection methods include spectrophotometry,electrochemical method,fluorescence spectroscopy,and instrument detection methods.These methods can only be used for quantitative or qualitative analysis.Although surface-enhanced Raman scattering(SERS)is excellent in qualitative analysis,quantitative analysis is difficult,and the fluorescence spectrum is just the opposite.The effective combination of the two methods will make up for each other and achieve on-site qualitative and quantitative detection.Due to the sensitivity of fluorescence and the qualitative analysis capability of SERS,dual-mode probes have been used in contaminant detection,optical coding and in vivo imaging,but the construction of dual-mode probes is the key to this field and the most challenging of.This paper summarizes the development of fluorescent-SERS dual-mode probes in recent years,and uses a layer-by-layer assembly method to construct satellite-like dual-mode probes,which are used for quantitative and qualitative detection of uranyl.First,we use electrostatic interaction and amide bond layer-by-layer assembly to construct a fluorescent-SERS dual-mode probe.By adjusting the ratio of cadmium telluride quantum dots and gold nanoparticles,and measuring their fluorescence intensity and mixed rhodamine-6G Raman signal intensity,the optimal ratio between the two is optimized.Transmission electron microscopy analysis distribution and elemental analysis proved that the synthesis was successful.Secondly,the photostability of the probe and the change of fluorescence intensity at different pH were studied and the SERS signal peak intensity of uranyl ions was measured.The sensitivity,selectivity and anti-interference of fluorescence and SERS detection of uranyl ions are also studied.The results show that the probe has good stability,high sensitivity for uranyl detection,and good selectivity and anti-interference ability.Finally,the recovery experiments in four actual water samples were used to verify their practical application ability.The results show that the probe can achieve the detection of uranyl in actual samples.This work will provide a more accurate and convenient method for the detection of uranyl,as well as provide new ideas for the detection of other pollutants.