33results about How to "Enhanced Raman scattering effect" patented technology

The invention relates to a surface enhanced raman scattering substrate and a preparation method thereof. The surface enhanced raman scattering substrate comprises a spherical empty shell and a film, wherein the film covers an upper half spherical surface of the spherical empty shell to form a composite micro-cavity structure, the spherical empty shell is the empty shell of any one of ZnO, TiO2, Al2O3, GaN and Al, and the film is an Ag film or an Au film. The preparation method of the substrate comprises the following steps: self-assembling an array template, adjusting the array template, depositing any one of ZnO, TiO2, Al2O3, GaN and Al on the array template, annealing the template in a nitrogen atmosphere, and depositing the Ag film or the Au film on the annealed array template. The multi-polar mode of the composite micro-cavity structure is coupled with a resonance mechanism, so that the advantages of simplicity in operation, rapidness in detection and high sensitivity can be realized, and the application prospect in the fields such as food security, stimulant detection and the like is wide.

The invention discloses a surface-enhanced Raman spectroscopy method capable of quantitatively detecting polychlorinated biphenyls, comprising the following steps: preparing uniform gold-coated silica nanoparticles, and using a coupling agent to fix the core-shell nanoparticles on Build a SERS substrate on a quartz glass sheet; connect the PCB aptamer to a thiol group at one end, and then covalently connect to the surface of the gold shell layer of the nanoparticle through the thiol group; soak the prepared SERS substrate in a solution containing the PCB, and wait for a sufficient time Take it out, wash it with deionized water, and then perform Raman spectroscopy measurement. The gold-coated silica nanoparticles prepared in the present invention have good morphology and particle size uniformity, and its plasmon resonance absorption occurs at 750nm, and at 785nm ‑1 There is a strong SERS enhancement effect under laser excitation.

The invention provides a method for preparing a multi-branched gold-silver composite nanomaterial with surface-enhanced Raman scattering characteristics. The preparation steps of the present invention are as follows: dissolving silver nitrate and polysorbate 80 in deionized water, and ultrasonically dispersing; adding gold targets, laser irradiation, centrifugation, and drying to obtain Ag@Au bimetallic nanoparticles; Ultrasonic dispersion of @Au bimetallic nanoparticles in deionized water, adding chloroauric acid aqueous solution and ascorbic acid aqueous solution, and reacting at room temperature for 2-3min to obtain the initial multi-branched Ag@Au composite nanomaterial dispersion; the obtained dispersion was mixed with The ethanol solution of silver nitrate is mixed, and after laser irradiation, centrifugation, washing and drying, a multi-branched gold-silver composite nanometer material is obtained. The preparation method of the invention is simple, controllable, environment-friendly and low in cost, and the obtained composite nano material has a small size (~50nm), and has excellent performance in surface enhanced Raman scattering.

Provided are a high-stability, non-polarisation-dependent, surface-enhanced Raman scattering substrate, and the preparation and use thereof, wherein the preparation technique belongs to the field of material physical chemistry, the use thereof belongs to the fields of light scattering science and surface plasma science, and the substrate is a regular array formed by an equilateral trimer of gold nano-particles in a periodic arrangement. The preparation process involves: firstly, preparing, on an aluminium substrate, a layer of a periodic array of extremely thin alumina nano pit equilateral trimers by means of electrochemical corrosion; then, depositing a layer of extremely thin gold nano-film on the array; and then, annealing the nano pit array substrate with the gold film deposited thereon to obtain a gold nano-particle equilateral trimer periodic array, i.e. the high-stability, non-polarisation-dependent, surface-enhanced Raman scattering substrate. The substrate has the prominent advantage of all-angle stable output of a surface-enhanced Raman scattering signal within a full range of 360¡ã independent of an excitation light polarisation direction during the process of surface-enhanced Raman scattering detection.

The invention discloses a preparation method and application of a cancer marker detecting system based on a silver aggregate-polymer and a gold nanowire array. The preparation method is characterizedby comprising the following steps: (1) preparation of a silver aggregate-polymer SERS immunoprobe; (2) preparation of a gold nanowire array substrate; and (3) assembling of a cancer marker detecting system. According to the application of the cancer marker detecting system, the cancer marker detecting system based on the silver aggregate-polymer and the gold nanowire array is subjected to spectralmeasurement by a raman spectrometer, and the concentration of antigen in a phosphate buffered solution which contains to-be-measured antigen can be obtained by calculation according to the quantitative relation between the spectral intensity and the concentration of the antigen. The preparation method and application of the cancer marker detecting system based on the silver aggregate-polymer andthe gold nanowire array have the advantages that while the relatively low detection limit is obtained, the specificity and repeatability of a detection result are improved.

Belonging to the technical field of laser Raman detection, the invention in particular relates to a flower-like silver / graphene oxide / gold nanostar sandwich structure SERS active substrate and a preparation method thereof. The flower-like silver / graphene oxide / gold nanostar sandwich structure SERS active substrate includes a carrier, and the carrier comprises a flower-like silver particle layer, a graphene oxide particle layer and a gold nanostar particle layer from bottom to top in order. According to the sandwich structure substrate constructed by the invention, the gold nanostar particles and flower-like silver particles in each layer have plasma resonance coupling effect, and the gold nanostar and flower-like silver particles between each layer also have plasma resonance coupling effect, so that the sandwich structure substrate provided by the invention has more excellent surface enhanced Raman scattering effect than single-layer substrates.

The invention relates to a surface-enhanced Raman scattering substrate based on a metal nanobowl and a preparation method thereof. The surface-enhanced Raman scattering substrate based on a metal nanobowl is composed of a polymer nanobowl and a metal film, and the metal film covers the inside of the polymer nanobowl surface and outer surface; the enhancement factor is 10 based on the metal nanobowl surface-enhanced Raman scattering substrate 7 ~10 9 , the enhancement factor is the ratio of the Raman signal intensity of the dye solution with the same concentration on the enhanced substrate and the non-enhanced substrate. The enhanced substrate is based on the metal nanobowl surface-enhanced Raman scattering substrate. The invention has no metal film; the preparation method is as follows: the polymer nano bowl is used as a substrate, and a metal film is vertically sputtered on the polymer nano bowl to prepare a surface-enhanced Raman scattering substrate based on the metal nano bowl. The preparation method of the invention is simple, and the prepared surface-enhanced Raman scattering substrate based on the metal nano bowl has remarkable enhancement effect.

The present invention relates to a preparation method of side-by-side self-assembled composite nanostructure of polydopamine-coated gold nanorods and the resulting product. The method uses isopropanol and polyacrylic acid to induce side-by-side self-assembly of gold nanorods, and then uses polydopamine to coat A gold nanorod self-assembly structure, the obtained gold nanorods are ordered and assembled along the axial direction to form a side-by-side self-assembly structure of gold nanorods. The invention has simple operation, good repeatability, and low cost, and the self-assembled composite nanostructure of side-by-side gold nanorods coated with polydopamine has good plasmon resonance optical properties, and exhibits good photothermal effect and surface-enhanced Raman scattering effect, good photothermal conversion efficiency, good heat resistance, and has good application prospects in the field of nano-photothermal diagnostic agents and optical sensing.

Belonging to the technical field of laser Raman detection, the invention in particular relates to a flower-shaped silver@graphene oxide@gold nanostar core-shell structure composite particle SERS active substrate and a preparation method thereof. The core-shell structure composite particle is composed of a core layer of a single grain flower-shaped silver particle, a middle coating layer of graphene oxide and an outermost layer of a gold nanostar particle. The core-shell structure composite particle serves as the SERS active substrate. Being visible under an optical microscope, the SERS active substrate can be used for high efficiency single particle SERS detection. According to the invention, gold nanostar particles and flower-shaped silver particles are combined for the first time, the excellent surface plasma resonance coupling effect between gold nanostar and flower-shaped silver particles endows the substrate with more excellent surface enhanced raman scattering effect than monolayer particles.

The invention discloses an immune base preparation method and an antigen or antibody immunoassay method. According to the immune base preparation method, a silicon slice is modified by using gold or silver nanoparticles, and antibodies / antigens are modified on the surfaces of the gold or silver nanoparticles, thereby being used for capturing antigens / antibodies to be assayed. According to the antigen or antibody immunoassay method, an immune base which is prepared by using the immune base preparation method and gold or silver nanoparticle immunoprobes is used, an immune base-antigen / antibody-immunoprobe three-layer sandwich structure is formed through an antigen-antibody immune complex reaction, and the assay on the antigens / antibodies to be assayed is realized in a manner that the characteristic dactylograms of Raman markers on the surfaces of the immunoprobes are assayed by using a surface-enhanced Raman scattering effect of the gold or silver nanoparticles. The method has the advantages that the sensitivity of the immunoassay can be greatly improved and the assay on high-flux multiple antigens / antibodies can be carried out.