Dual-functional Precious Metal Porous Material For Rapid Detection Based On Solid-phase Microextraction And Surface-enhanced Raman Spectroscopy

The development of science and technology has promoted economic development and improved human living standards.However,the unreasonable use of technology can also bring about some problems,such as pollution caused by illegal addition and illegal discharge,which may affect human health.In recent years,as people pay more and more attention to health,environmental pollution and food safety have received extensive attention.Pollutants in the environment and illegal additives in food may induce cancer,affecting the nervous system,immune system and reproductive system.In the detection process of actual samples,since the components of the actual samples are relatively complicated,complicated separation and enrichment processes are often required before detection,which takes a long time.Therefore,it is very important to develop rapid detection methods for complex systems.Surface-enhanced Raman spectroscopy(SERS)is a fast,sensitive,non-destructive method,which is not interfered by water.Solid phase microextraction(SPME)is a new type of sample pretreatment technology with simple equipment.It integrates sampling and extraction and suitable for on-site testing.Besides,it does not need organic solvents,avoiding secondary pollution to the environment.SPME-SERS can integrate sampling,extraction and detection to improve detection efficiency.In this paper,aiming at the on-site high-efficiency detection of different complex systems,we prepared SERS substrates with high enhancement factor,which can achieve rapid on-site detection.We realized rapid detection in different systems by combining SPME and SERS.1.In Chapter 2,we prepared a silver extraction fiber with a three-dimensional structure.The prepared extraction fiber can also be used as a SERS substrate and has a good enhancement effect.When enriching the analyte,we use a mechanically driven SPME-SERS to reduce the thickness of the diffusion layer and shorten the extraction time.It is expected that the entire sampling and detection process can be completed within 1 minute,which improves the detection efficiency.We detected malachite green and crystal violet in aquaculture water,and the results showed that in actual water samples,signals can be obtained quickly and a good linear relationship can be obtained.Our work is expected to be very useful on detection of analyte in solution in the future.2.In Chapter 3,we prepared a Au-Ag substrate,which has high sensitivity and good stability.Combining SPME and SERS,the substrate was inserted into the fish body for extraction for 10 minutes,then the substrate was taken out for SERS signal collection,which can realize rapid detection in vivo.When the fish is put in the malachite green solution,the signals can be detected in the fish.After leaving the malachite green solution for a period of time,it is still possible to detect signals.Sampling and detection at different time can help understand the metabolism of the fish.Our work provides a detection method in complex systems in the future.