Preparation Of Biological Template SERS And Metamaterial Optical Fiber SPR Sensors And Detection Of DNA Molecules

Surface enhanced Raman spectroscopy?SERS?,surface plasmon oscillation?SPR?sensors are based on plasmon oscillation technology and have many advantages:miniature,non-marking detection,easy to carry,cheap to prepare,and superior performance.It can be applied to environmental pollution,pesticide residues,biological detection and so on.With the development and progress of technology,the preparation materials of SERS and SPR sensors are also gradually improved.Biomaterials?as a green,cheap,high-performance substrate?and metamaterials?with unique structural and optoelectronic properties,are generally divided into Nano-pillar arrays and multi-layer structures?have gradually entered people's field of vision,and biological SERS substrates and metamaterial SPR sensors have also shown stronger detection limits and better performance,and we detect and bind DNA molecules.Molecular dynamics and dissociation have been studied and combined,and it has been found that our DNA bioassay can be successfully applied through our substrate,which also provides a good platform for SERS and SPR in medical applications.Based on the high-performance SERS mechanism of biomaterials,the unique structure and optoelectronic characteristics of metamaterials combined with SPR fiber optic sensors and biological DNA molecular detection technology,a SERS substrate based on a graphene-silver nanoparticle-cicada wing hybrid system was fabricated.Graphene/ITO nanorod metamaterials/U-shaped annealed fiber optic sensors have shown good application prospects.?1?We prepared a SERS substrate based on a graphene-silver nanoparticle-cicada wing hybrid system,cut and clean the cicada wing appropriately,and then plate silver with a magnetron sputtering instrument.Finally,the prepared silver nanoparticle-cicada wing The substrate is simply immersed in polyacrylamine hydrochloride?PAH reagent?,GO dispersion,hydrazine hydrate solution to deposit graphene on the substrate for a certain period of time.The substrate has a very good detection limit(10^-15M)by R6G test.And good linearity parameters?R²=0.996?,based on the bioaffinity of graphene,the probe DNA molecules were bound to the SERS substrate by PBASE,and a good detection effect was obtained,which can detect 2 mM DNA reagents This shows that the biological SERS substrate we prepared has good performance and biological application prospects.?2?We prepared a graphene/ITO nanorod metamaterial/U-shaped annealed optical fiber sensor.First,a butane candle was used to heat a multi-mode quartz optical fiber into a U-shape,and then a gold film was plated on the U-shaped fiber through a gold mirror reaction.By forming a dense and suitable cluster of particles by annealing the gold film first,it provides a catalytic effect for ITO site-specific growth in the future.Then add a certain amount of indium oxide and tin oxide into the PECVD furnace,place the quartz fiber at a distance from the heating center,deposit the reactants on the U-shaped quartz fiber through a suitable argon gas stream,and finally use graphite to chemically synthesize graphite Ethylene is deposited on ITO nanopillars,and our SPR sensor has a good sensitivity?690.7 nm/RIU?by alcohol gradient test.We use PBASE as a bridge to bind DNA molecules to sensors and successfully complete experiments on the specificity of DNA molecules,which shows that our prepared sensors have a very promising application prospect.