155results about How to "Enhanced Raman signal" patented technology

Provided is a surface Raman and infrared spectroscopy double-enhanced detecting method based on graphene and nanogold compounding.According to the method, light sources, a lens, a graphene nanobelt and gold nanoparticle composite substrate, an infrared Fourier spectrograph and a Raman spectrometer are included.Infrared light waves and visible light waves emitted by the infrared light source and the laser light source respectively pass through a beam combiner and then irradiate the graphene nanobelt and gold nanoparticle composite substrate, after the light waves and trace molecules adsorbed on the substrate interact, reflected light is gathered by the focusing lens to enter the infrared Fourier spectrograph, and meanwhile scattered light is gathered into the Raman spectrometer.Raman scattering signals of the trace molecules can be enhanced through the local area plasma effect of the gold nanoparticles, and meanwhile infrared absorption spectrum signals of the trace molecules can be dynamically enhanced through the graphene surface plasma effect within the broadband range.According to the method, double enhancement of surface Raman and broadband infrared spectroscopy signals is achieved on the same substrate, and the advantages of being wide in enhancement wave band, high in detecting sensitivity, wide in detected matter variety range, good in stability and the like are achieved.

The invention relates to a surface-enhanced Raman scattering probe and a preparation method thereof. The probe is an interlayer structure and consists of a core precious-metal nano-rod, an intermediate sandwich layer and a precious-metal shell layer which grows and is formed on the outer surface, wherein a Raman signal molecule is wrapped inside the intermediate sandwich layer. The preparation method comprises the following steps that: the surface of the precious-metal nano-rod absorbs or is coupled with the Raman signal molecule, then the Raman signal molecule is wrapped to form the intermediate sandwich layer through silicon dioxide or polyelectrolyte, and then the precious-metal shell layer grows and is formed outside the intermediate sandwich layer. Through the surface-enhanced Raman scattering probe with the sandwich structure, strong local electromagnetic density is produced through the interaction of the surface plasma between the gold nano-rod and the outer metal shell layer, so the Raman signal is greatly enhanced, the weaknesses that a two-dimensional underlay is difficult to repeat, is expensive and is complicated can be overcome, and at the same time the size of the surface-enhanced Raman scattering probe is smaller than 200nm, biological detection of living bodies and application of biological imaging can be facilitated when the surface-enhanced Raman scattering probe is used as a biological probe.

An device for Raman spectroscopy such as surface enhanced Raman spectroscopy (SERS) is disclosed herein. Various embodiments may be utilized to prepare a SERS substrate using several deposition techniques such as pulsed laser deposition. Some embodiments optimize coverage, volume, or elements of SERS active metals. The method is a single step inexpensive method for preparing a SERS active substrate. In some embodiments a coating layer underneath the SERS active metals is utilized for additional enhancements.

The invention provides a preparation method of a microfluidic monolithic column chip and an application of the chip in raman detection. The method comprises the steps that a polydimethylsiloxane (PDMS) microfluidic chip is prepared; a porous monolithic column solution is prepared; a monomer, a crosslinking agent, a pore-forming agent and a photoinitiator are subjected to ultrasonic mixing; nitrogen is supplied for deoxygenization; and finally the monolithic column solution is put in an ice bath for preservation. The solution is injected into a microfluidic chip pipeline, sealed and subjected to ultraviolet exposure, methanol washing is adopted for removing the pore-forming agent and the unreacted monomer, deionized water is used for washing sufficiently, a silver microsphere solution is injected into the microfluidic chip, ultra-sensitive raman real-time detection of a to-be-detected sample is achieved by utilizing silver microsphere enrichment and a surface raman enhancement effect, and a detection limit of the method can reach 10-12M. The method is convenient, flexible, low in cost, low in energy consumption, and convenient to popularize, and is widely applied to the fields of serum marker detection, gas marker detection, environmental monitoring, food safety and the like.

The invention relates to a preparation method of a high strength graphene based composite paper. Generally, the method includes: adopting a graphene oxide colloid and chopped carbon fiber mixed solution as the precursor to carry out hydrothermal reaction with a silver-ammonia solution, conducting in-situ one-step compounding of silver nanoparticles on the graphene oxide and carbon fiber surface, and then performing drying and low-temperature stepped heating reduction treatment so as to obtain a graphene / silver / carbon fiber three-phase composite paper. By controlling the ratio of the composite carbon fiber, the method provided by the invention synthesizes the graphene based three-phase composite paper with optimum mechanical properties and enhanced hydrophobicity and electrical conductivity. Compared with uncompounded graphene oxide paper, the electrical conductivity is increased by two orders of magnitude, and the hydrophobicity is strengthened. Compared with graphene / silver two-phase composite paper, the mechanical strength is increased by 80%. The composite paper can be used as a Raman enhanced substrate and a novel paper material. The method is simple and is easy for control, and is convenient for industrial production. The prepared self-support composite paper has broad application prospects in food safety, biomedicine, packaging materials and other fields.

The invention discloses a core-shell nanogold biological probe with a high SERS (surface enhanced Raman scattering) effect and a preparation and an application thereof. The preparation comprises the following steps: assembling a section of DNA sequence and Raman micromolecules on the surface of nanogold with a small particle diameter; and further generating a gold shell with a certain thickness on the surface of a core of the nanogold, wherein a gap with a certain size exists between the core and the shell, the Raman micromolecules are in the gap, and due to specificity of the structure, high-efficiency and uniform SERS signals are obtained. The Raman micromolecules are in the gap with the fixed size between the core and the shell of the nanogold, so that the SERS signals generated in areas of the molecules, namely hotspot areas, are basically consistent and have good repeatability; the biological molecules are assembled on the surface of the prepared core-shell nanogold biological probe, so that a surface receptor of a target cell can be recognized specifically, the target cell can be detected and imaged by a laser Raman spectroscopy, and Raman scattering value increase on the obtained surface can show the expression of the surface receptor of the target cell efficiently; and the core-shell nanogold biological probe is also applicable to biological sensor detection, biomolecular detection and other research fields.

The invention provides a Raman spectrum measurement system. The Raman spectrum measurement system comprises a linear polarization laser source, a total reflection element located at one side of the linear polarization laser source, a porous metallic film directly or indirectly clinging to the total reflection element and a Raman probe, wherein an interface of the total reflection element and the porous metallic film is used as a total reflection surface. The linear polarization laser source generates linear polarization laser beams with a magnetic field vibration direction parallel to the total reflection surface; the laser beams enter into the total reflection element and undergo total reflection on the total reflection surface; a transverse magnetic polarization evanescent field generated after total reflection excites resonance of surface plasma of the porous metallic film, which leads to reinforcement of a magnetic field at the inner / external surface of the porous metallic film; the reinforced magnetic field excites a Raman signal of the molecule of a to-be-measured object located on the inner / external surface of the porous metallic film; and the Raman signal is detected by the Raman probe. The Raman spectrum measurement system provided by the invention can substantially improve a Raman enhancement factor of the porous metallic film only by adjusting the polarization state of incident light and allowing the incident light to be in a transverse magnetic polarization state.

The invention relates to a preparation method for bionic nano-silver. Silver nitrate and natural polymer or derivative of the natural polymer are raw materials and react in a water solution under stimulation of sunlight or visible light. The natural polymer is protective agents, reducing agents and photosensitizer and generates the nano-silver under stimulation of sunlight or low-frequency visible light at the room temperature. The prepared nano-silver has high safety under the protection of the natural polymer, can be applied to biomedical materials or daily chemical products, gives play to an antibacterial function, and can obviously reinforce the Raman signals of molecules to be detected when used as Raman base materials. The preparation method for the bionic nano-silver is simple, reliable, capable of meeting the requirements for the shape and performance of the nano-silver in the field of biomedicine or spectrums, good in biosecurity, capable of controlling the shape and the particle size of products, and wide in application range.

The invention discloses a ZnO-Ag surface enhanced Raman scattering substrate and detection of organic pollutants with the substrate. The preparation method for the substrate comprises the following steps: the first step, ITO conductive glass is subjected to ultrasonic cleaning with acetone, alcohol and deionized water one by one and dried in the air; the second step, organic additives are added in a zinc nitrate solution, a first mixed liquid is formed, after the first mixed liquid is stirred for 30 min, an ammonia-water solution with a mass fraction of 25% is dropwisely added in the first mixed liquid, a second mixed liquid is formed, the processed ITO conductive glass from the first step is soaked in the second mixed liquid, after the water bath is at a constant temperature, the ITO conductive glass is placed in a baking box and baked for 60-100 min, a white and uniform ZnO layer is formed on the surface of the ITO conductive glass; the third step, Ag nanoparticles are deposited on the prepared ZnO nanolayer from the second step, and a ZnO-Ag surface enhanced Raman scattering substrate is obtained. The preparation method is simple. The prepared substrate has high sensitivity and good stability and can be used repeatedly.

It has been discovered that specially structured metallic films containing voids can deliver a hugely enhanced surface enhanced Raman spectroscopy (SERS) effect. By selecting a particular size and geometry for the voids, metallic films can be provided which have an enhanced photon-to-plasmon conversion efficiency for incident radiation of a predetermined wavelength. Controllable surface-enhanced absorption and emission characteristics may thus be provided, which are useful for SERS and potentially also other optical spectrometry and filtering applications. With such a large Raman signal, the invention enables fast, compact and inexpensive Raman spectrometers to be provided opening up many new application possibilities.

An apparatus and method for obtaining Raman spectra that are suitable for continuous real-time monitoring, utilizing the basic technique of Raman spectroscopy in cooperation with wavelength-selective optical amplification are described. The invention improves the detection sensitivity of conventional Raman spectroscopy by orders of magnitude by providing strong wavelength-selective optical amplification and narrowband detection of the intense driving laser and the weak Raman signal(s), thereby essentially eliminating the driving laser signal from the detector and detection electronics. The invention is effective for both Stokes and anti-Stokes Raman lines, and either where the incident laser wavelength is fixed and the Raman spectrum is recorded by analyzing the output of the fiber amplifier with a spectrometer, or where the detection wavelength is fixed and the Raman spectrum is recorded by tuning the wavelength of the laser.

The invention relates to a surface-enhanced Raman technology based on signal-off and used for detecting intracellular telomerase activity. According to the technology, graphene, carbon nitride, MoS2, SiO2 and the like are taken as carriers, nano-gole or nano-silver with controllable dimension and morphology or a composite magnetic nano-particle with a core-shell structure is supported by the carriers, and then a hairpin probe containing a telomerase primer and a Raman molecule beacon is fixedly disposed on the nano=particle surface, so that the high-sensitivity high-selectivity SERS detection method based on signal-off is established. When a target exists, the primer extends and generates a DNA chain with a repeat sequence under the effect of telomerase, and the DNA chain is hybridized with the probe molecule, then the DNA hairpin structure is opened, a Raman signal molecule with the single-chain labeled end is far away from a Raman substrate, the Raman signal is reduced, and high-sensitivity detection on telomerase is realized. The probe prepared by taking Hela cervical carcinoma cell as a model realizes intracellular telomerase activity detection and dynamic detection on intracellular telomerase activity variation under effect of a telomerase inhibiting medicament. By using multiple cells for imaging, the probe is confirmed to be capable of distinguishing tumor cells and normal cells.

The invention discloses a biomolecular functionalized graphene / gold nano-particle composite film and a preparation method thereof, belonging to the technical field of inorganic film material. The composite film is obtained by self-assembly of graphene reduced and functionalized by bovine serum albumin and gold nano-particle electrostatic layer, wherein the chemical general formula is PEI / BSA-G- / (BSA-G+ / AuNPs)n; PEI is polyetherimide; BSA-G- is laminated bovine serum albumin functionalized graphene with negative charge; AuNPs is gold nano-particle; n is the layer number of multilayer film; andthe thickness of the film is 15-500 nm. The laminated graphene with negative charge and gold nano-particles are assembled on a substrate repeatedly by electrostatic layer assembly technology to obtain an ordered and high-dispersion graphene / gold nano-particle three-dimensional composite film; and the instrumentation of the graphene material is achieved. The composite film can be widely applied inelectro-catalysis and sensing field, and as a surface enhanced Raman substrate.

The invention discloses a large-area metal nano-structural substrate for surface-enhanced Raman and a preparation method thereof. The large-area metal nano-structural substrate for the surface-enhanced Raman consists of a nano-scale structural substrate consisting of different phase alloy materials and a nano-thickness metal material deposited on the substrate. The metal nano-structural substrateprovided by the invention has good Raman enhancing effect, and can be widely applied in the fields of physics, chemistry, materials science, biomedicine and the like. The preparation method for the large-area metal nano-structural substrate for the surface-enhanced Raman uses an alloy material consisting of different phases as a primary template, adopts a selective plasma etching method to etch the nano-structural substrate, and then adopts an ion beam sputtering method to deposit the nano-thickness metal material on the nano-structural substrate so as to form the surface-enhanced Raman substrate based on different phase metal materials; and the preparation method has mature industrial technology and low production cost, and can implement industrialized mass production.

The invention discloses an optical fiber type sensor system based on surface plasma resonance and stimulated Raman scattering. The system comprises a broadband light source, a P-type polaroid, a focusing convex lens, a polarization controller, an optical fiber beam splitter, an optical fiber inclined end, a surface plasma resonance (SPR) probe and an optical fiber spectrometer, wherein the P-type polaroid is positioned between the broadband light source and the focusing convex lens; the focusing convex lens optically couples the polarization broadband to the polarization controller; the polarization controller is connected with one input end of the optical fiber beam splitter, and the optical fiber spectrometer is connected with the other input end of the optical fiber beam splitter; the optical fiber inclined end is connected with one output end of the optical fiber beam splitter, and the SPR probe is connected with the other output end of the optical fiber beam splitter; the free end of the optical fiber inclined end is inclined; the SPR probe comprises an optical fiber; the end face of an exposed fiber core is provide with a first metal film, and the periphery of the exposed fiber core is provide with a second metal film; a nano-film is arranged on the surface of the second metal film; and a sensitive film is arranged on the nano-film. The system has the advantages of high universality, sensitivity and stability, and capable of realizing remote monitoring.

The invention provides an SERS substrate based on a metal dot matrix. The SERS substrate comprises a silicon substrate body, the metal dot matrix formed on the silicon substrate body and a hydrophobic layer arranged in an area outside the metal dot matrix. A metal layer of the metal dot matrix is made of gold or silver or copper. The area outside the metal dot matrix on the substrate has hydrophobicity, the positions of metal dots of the metal dot matrix are relatively hydrophilic, therefore, to-be-detected substances can be better enriched on the metal dots, and Raman signals can be enhanced. The invention further provides a preparation method of the substrate, a method for conducting Raman detection through the substrate and an SERS chip based on the metal dot matrix.

The invention discloses a substrate material and in particular relates to a substrate material capable of generating enhanced Raman effect excitation hotspot on the surface, a method for generating the extremely strong surface enhanced Raman effect through hotspot excitation in a transient process and representation of the surface enhanced Raman effect in the transient process. According to the substrate material, a surface structure capable of generating an enhanced Raman effect hotspot is constructed through Ag vapor deposition after in-situ growth of a ZnO nanometer rodlike array on a galvanized silicon wafer, and furthermore, the enhanced Raman effect hotspot can be excited through reasonable utilization of the capillary effect between a specific solvent and the surface structure; besides, the invention also discloses a representation method for the excitation method. The process is simple and stable, the prepared substrate material can acquire further-enhanced Raman spectrums through the hotspot excitation method, and the substrate material has high sensitivity and good selectivity in explosive detection.

The invention mainly belongs to the technical field of material preparation and SERS detection and analysis, and particularly relates to an ultra-infiltration nano branched gold SERS micro-chip and apreparation method thereof. The ultra-infiltration nano branched gold SERS micro-chip can be used for detecting biomolecule miRNA. The ultra-infiltration nano branched gold SERS micro-chip successively comprises ITO glass, a titanium layer, a gold layer, a nano branched gold layer and a super-hydrophilic array-super-hydrophobic surface; and the super-hydrophilic array-super-hydrophobic surface isspecifically prepared by arranging super-hydrophilic array points on a super-hydrophobic surface in a distributed manner, and the super-hydrophilic array points are used for fixing to-be-detected liquid drops. To-be-detected liquid drops with different concentrations are dropwise added on different hydrophilic points of the same SERS micro-chip, and the to-be-detected liquid drops with the different concentrations can be simultaneously detected to improve detecting accuracy and shorten detecting time.

The invention discloses a tri-metal nano particle with an asymmetric structure, a preparation method and application thereof. The preparation method comprises the steps: utilizing a golden rod as a seed and a silver nitrate solution as a metal precursor, utilizing a seed growing method to prepare rod-like template nano particles with core-shell structures and with silver coated outside the golden rod, centrifugally dispersing the particles in ultrapure water; utilizing a modified electric displacement reaction and a common reduction reaction, adding chloropalladic acid to the obtained aqueous solution containing template nano particles, utilizing ascorbic acid as a reducing agent and standing at room temperature; adjusting the molar ratio of silver nitrate and chloropalladic acid and the amount of surfactant and ascorbic acid, and obtaining dandelion-shaped nano particles under the action of Oswald ripening effect, wherein the brace is of a golden rod structure; one end of the golden rod is coated with spherical silver-palladium alloy with a branch-like structure and the other end is a pure golden rod. In the organic reaction using palladium as a catalyst, the palladium can be used as the catalyst with good activity and can be used as the tracking and detection for Raman spectrum signals.

The invention discloses a homogeneous phase multi-component immunoassay method based on a surface plasma coupling effect. A gold nanosphere probe (Raman reactive dyes and capture antibodies are embellished on the surface of the gold nanosphere probe) and a gold nanorod probe (Raman reactive dyes and detection antibodies are embellished on the surface of the gold nanorod probe) are respectively prepared; the Raman reactive dyes carry sulfydryl self and are free of fluorescent background; and the antibodies are subjected to TCEP (Tris(2-carboxyethyl) phosphine) reduction treatment. The antigen of an object to be tested has immune sandwich reaction with the antibodies so as to generate an immune complex, so that the distances between nano particles are shortened, the surface plasma coupling effect is generated, the Raman signals of the surface embellishing dyes on the surfaces of the nano particles are significantly enhanced, and the SERS (Surface Enhanced Raman Scattering) quantitative analysis of the antigen is realized by using the coupling enhancing effect. The method is simple and rapid, the detection process needs only one step of operation without repeated elution or separating samples, the synchronous quantitative analysis to a plurality of components in the samples is realized with high sensitivity and good uniqueness, and thus the method is expected to become a new method in proteomics research and drug therapeutic effect evaluation.

The invention discloses a multilayer core-shell structured Au@SiO2@Ag@SiO2 nano composite material and a preparation method therefor and belongs to the technical field of preparation of nano composite materials. The method comprises the steps of firstly preparing a Au@SiO2 core-shell structured nano-material, then, sequentially adding ascorbic acid, silver nitrate and sodium hydroxide into the Au@SiO2 core-shell structured nano-material, then, adding an amino silane solution into the Au@SiO2 core-shell structured nano-material, then, adding a sodium silicate solution into the Au@SiO2 core-shell structured nano-material, carrying out room-temperature stirring, then, shifting the mixture in oil bath with 93 DEG C for reaction, finally, stopping heating, and carrying out natural cooling. The nano composite material has the characteristics of high detection sensitivity, strong Raman signal, good reproducibility and high accuracy. According to the preparation method, the nano composite material is mainly prepared by chemical methods, and defects caused by crystal lattice mismatch are reduced through coating different noble metals with ultrathin SiO2 layers, so that Raman signals of target molecules are further strengthened. A Raman probe prepared from the nano composite material is easy to functionalize, so that the range of action of the Raman probe is wide.

The present invention discloses a gold nanostar @ gold-silver alloy nanometer base material with high Raman activity and a preparation method thereof and belongs to the technical field of nanometer materials. The method is characterized in that gold nanostar particles are used as cores to prepare gold nanostar @ silver core shell nanoparticles through reduction of silver nitrate on surfaces, and agold nanostar @ gold-silver alloy nanometer material with a tiny narrow slit structure is prepared by reducing chloroauric acid on the surfaces of gold nanostar @ silver and by utilizing the replacement and migration rule of gold and silver atoms and used as a Raman base material. The material of the present invention has the following advantages: 1) a strong hot spot region can be formed by thetiny narrow slit structure of gold nanostar @ gold-silver alloy nanoparticles, thereby greatly enhancing Raman signals of beacon molecules in this region; 2) gold nanostar @ gold-silver alloy nanoparticles are stable in Raman enhancement effect and good in reproducibility, thereby preventing loss of Raman signals of beacon molecules; and 3) the nano material can be used as a Raman label and used for quickly detecting harmful substances in food and environment with high sensitivity in combination with biomolecules such as antibodies and aptamers.

The invention relates to a surface enhanced Raman spectroscopy (SERS) sensing base plate. A first embodiment of the invention comprises a base plate and a nanometer straight column structure formed by a plurality of layers of metal / dielectric substance materials growing on the base plate, wherein the nanometer straight column structure is provided with a configuration and is roughly parallel to the normal direction of the base plate after growing up.

The invention provides an enhanced Raman substrate for detecting streptomycete hyphae, preparation and use methods thereof. The detection substrate is composed of a filter membrane layer (1), a monodisperse nanometer particle layer (2) and a metallic coating (3) from bottom to top. The detection substrate is high in detection speed and sensitivity. The preparation process is as follows: 1) self-assembling on the filter membrane layer (1), thereby acquiring the monodisperse nanometer particle layer (2); 2) preparing a gold nanoparticle layer on the monodisperse nanometer particle layer (2); and 3) taking gold nanoparticles in the gold nanoparticle layer as a nucleus for growing the metallic coating (3), thereby acquiring the detection substrate. The preparation method is simple and fast. The detection substrate can be used for detecting if a detected sample contains the streptomycete hyphae; and the Raman spectrum of the sample solution is collected for detecting if the streptomycete hyphae are contained in the detected sample and detecting the content of the streptomycete hyphae. The method has wide application prospects in the fields of clinical detection, inspection quarantine, environment monitoring, and the like.

The invention discloses a preparation method of Ag / MXene-Ti3C2 composite material with high SERS activity. The sodium citrate and MXene-Ti3C2 are used as reducing agents, and the sodium citrate and the polyvinylpyrrolidone solution are sequentially added to silver nitrate solution at a room temperature, then the MXene-Ti3C2 solution is added into the mixed solution after uniform mixing, and the Ag / MXene-Ti3C2 composite material is obtained after water bath. The method is simple in operation and low in cost, the prepared Ag / MXene-Ti3C2 composite material can be taken as a substrate to enhance the probe molecule Raman signal, the enhancement effect is excellent, and the enhancement factor can reach 2.24*105.

The invention relates to a raman spectrometer for detecting a specific narrow wave number range. The raman spectrometer comprises laser transmitting equipment, spectrum collection equipment and data processing equipment, wherein the laser transmitting equipment is used for obtaining a power regulated exciting light beam; the spectrum collection equipment is used for lighting the power regulated exciting light beam to the surface of a sample to perform raman scattering, filtering off oriented rayleigh scattered light to obtain oriented raman scattered light, and allowing the oriented raman scattered light to be received by a receiver; the data processing equipment is computer equipment connected with the receiver, and is used for formation, analysis and judgment of an obtained raman spectrum; the receiver is a single photon detector; and the oriented raman scattered light is finally received by the single photon detector. Compared with the prior art, the raman spectrometer can realize high-efficiency utilization of a photon, and can realize rapid and high-sensitivity detection of the raman spectrum of the specific narrow wave number range.

The present invention is related in general to chemical and biological detection and identification and more particularly to systems and methods for the rapid detection and identification of low concentrations of chemicals and biomaterials using surface enhanced Raman spectroscopy.

The invention belongs to the technical field of functional materials, and relates to a preparation method and application of a Raman enhancer. The Raman enhancer is a microsphere with a Raman enhancement effect, PS microspheres form the core, and Au / Cu nanoparticles form the shell. The preparation method comprises the following steps: preparing the PS microspheres, depositing Cu on the surfaces of the PS microspheres to obtain Cu-PS by virtue of an in-situ chemical reduction method after activation treatment, and reducing chloroauric acid with sodium citrate to generate a gold nanoparticle for deposition on the Cu-PS, thereby preparing a Au / Cu-PS composite microsphere. According to the prepared Au / Cu-PS composite microsphere, the Au / Cu nanoparticles are non-uniformly distributed on the surface of the PS microsphere to form relatively many hotspot positions, and after a background signal is cancelled through a program, so that a Raman signal can be greatly enhanced. The preparation method is easy to operate and controllable in process, and the prepared Au / Cu-PS composite microsphere can be used for Raman detection in food safety and environmental safety.