Preparation Of Flexible Cu-based Ag Nanostructure SERS Substrate And Its Application In SERS Biosensor

Surface-enhanced Raman scattering(SERS),as a molecular fingerprint detection technology,can be used to identify the structure of substances and has been widely applied in material science,food science,life science,archaeology,agriculture and other fields.The strength of SERS effect was a constant pursuit of the scientific research work,and the preparation of SERS substrate with high strength,high sensitivity,simple preparation process and low cost was also the core of the work of the scientific research.This paper based on the existing SERS technique,focus on problem of manufacturing method complex,high cost,which is difficult to be used in the field of the actual detection of SERS substrate for practical application.This paper produced a new type of Ag-Cu all metal flexible substrate with the highperformance by using efficient method of electrochemical deposition,which took a profound study of substrate performance.In order to further improve the performance of SERS substrate,we utilized graphene as the nanogap and designed a kind of flexible SERS substrate.Moreover,the properties of graphene and its role in SERS detection were thoroughly analyzed.And the effect of SERS substrate on in situ detection of chemical residues in practical application field was further studied.In this paper,the copper network with high mechanical strength and flexible was used to form the flexible SERS substrate,which can overcome the shortcomings of traditional hard metal substrate.Therefore,the cheap copper network shows a high cost performance and the porous structure of copper can be extracted to realize in-situ detection from the uneven surface by bending and scraping biological probe molecules.The main works were as follow:(1)we applied the electrochemical deposition method to deposit silver nanostructures on the surface of the copper network.The preparation process was simple and the low-cost.Different nanostructures were formed by changing the voltage and reaction time,and the growth of silver nanostructures with different morphologies was analyzed,and the property of SERS was detected from the substrate.The experimental results showed that the silver nanodendrite /copper net(AgD/Cu)flexible metal substrate provided a new idea for the fast and sensitive SERS detection of various analytes.(2)we applied the electrochemical deposition method and chemical vapor deposition successfully prepared silver nanoflower/graphene@copper net(AgNFs/G@Cu)SERS substrate with high uniformity and sensitivity.In addition,AgNFs/G@Cu SERS substrate has demonstrated excellent mechanical flexibility and practical application.Malachite green was used as the probe molecule and the substrate was extracted from the biological surface for testing.The experimental results show that AgNFs/G@Cu substrate can be used in pesticide detection,food safety,and biotechnology.