1049 results about "Raman scattering" patented technology

NERS-active structures for use in Raman spectroscopy include protrusions extending from a surface of a substrate. A Raman signal-enhancing material is disposed on at least one surface of a first protrusion and at least one surface of a second protrusion. The Raman signal-enhancing material disposed on the first protrusion projects laterally in a direction generally towards the second protrusion, and the Raman signal-enhancing material disposed on the second protrusion projects laterally in a direction generally towards the first protrusion. At least a portion of the Raman signal-enhancing projecting from the first protrusion and at least a portion of the Raman signal-enhancing material projecting from the second protrusion may be separated by a distance of less than about 10 nanometers. Raman spectroscopy systems include such NERS-active structures, and methods for performing Raman spectroscopy include irradiating an analyte proximate such a NERS-active structure and detecting Raman-scattered radiation scattered by the analyte.

A method for the high power generation and detection of terahertz radiation is presented. It comprises of an optical waveguide with a core, and a mostly hollow cladding or terahertz wave transparent material surrounding the core. The cladding region is a terahertz waveguide. A pump light source is coupled to the core to promote nonlinear optical process, such as Raman scattering, in the core which in turn leads to terahertz radiation being emanated or received through fiber cladding.

An apparatus for evaluating a target of interest of a living subject. In one embodiment, the apparatus has a first light source for generating a broadband light, a second light source for generating a monochromatic light, a beamsplitter optically coupled to the first light source for receiving the broadband light and splitting it into a reference light and a sample light, a reference arm optically coupled to the beamsplitter for receiving the reference light and returning it into the beamsplitter, and a probe having a working end placed proximal to a target of interest of a living subject, optically coupled to the beamsplitter and the second light source for receiving the sample light and the monochromatic light, delivering them from the working end to the target of interest, collecting from the working end a backscattering light and a Raman scattering light that are obtained from interaction of the sample light and the monochromatic light with the target of interest, respectively, and returning the backscattering light into the beamsplitter so as to generate an interference signal between the returned backscattering light and the returned reference light in the beamsplitter.

Disclosed herein is a SERS sensing surface device comprising a substrate supporting a plurality of nano structures, an exposed sensing surface upon the nano structures, wherein said surface includes at least one active SERS nano surface and at least one inactive SERS nano surface established in proximity to the active SERS nano. Also disclosed are methods for forming the array device, systems based on the array device, as well as methods for performing SERS with the array device.

The present invention provides a new class of Raman-active reagents for use in biological and other applications, as well as methods and kits for their use and manufacture. Each reagent includes a Raman-active reporter molecule, a binding molecule, and a surface enhancing particle capable of causing surface enhanced Raman scattering (SERS). The Raman-active reporter molecule and the binding molecule are affixed to the particle to give both a strong SERS signal and to provide biological functionality, i.e. antigen or drug recognition. The Raman-active reagents can function as an alternative to fluorescence-labeled reagents, with advantages in detection including signal stability, sensitivity, and the ability to simultaneously detect several biological materials. The Raman-active reagents also have a wide range of applications, especially in clinical fields (e.g., immunoassays, imaging, and drug screening).

The system and method of the present invention relates to using spectroscopy, for example, Raman spectroscopic methods for diagnosis of tissue conditions such as vascular disease or cancer. In accordance with a preferred embodiment of the present invention, a system for measuring tissue includes a fiber optic probe having a proximal end, a distal end, and a diameter of 2 mm or less. This small diameter allows the system to be used for the diagnosis of coronary artery disease or other small lumens or soft tissue with minimal trauma. A delivery optical fiber is included in the probe coupled at the proximal end to a light source. A filter for the delivery fibers is included at the distal end. The system includes a collection optical fiber (or fibers) in the probe that collects Raman scattered radiation from tissue, the collection optical fiber is coupled at the proximal end to a detector. A second filter is disposed at the distal end of the collection fibers. An optical lens system is disposed at the distal end of the probe including a delivery waveguide coupled to the delivery fiber, a collection waveguide coupled to the collection fiber and a lens.

The invention provides a system and method for automatic real-time monitoring for the presence of a pathogen in water using coherent anti-stokes Raman scattering (CARS) microscopy. Water sample trapped in a trapping medium is provided to a CARS imager. CARS images are provided to a processor for automatic analyzing for the presence of image artifacts having pre-determined features characteristic to the pathogen. If a match is found, a CARS spectrum is taken and compared to a stored library of reference pathogen-specific spectra for pathogen identification. The system enables automatic pathogen detection in flowing water in real time.

An analyte stage for use in a spectroscopy system includes a tunable resonant cavity that is capable of resonating electromagnetic radiation having wavelengths less than about 10,000 nanometers, a substrate at least partially disposed within the cavity, and a Raman signal-enhancing structure at least partially disposed within the tunable resonant cavity. A spectroscopy system includes such an analyte stage, a radiation source, and a radiation detector. Methods for performing Raman spectroscopy include using such analyte stages and systems to tune a resonant cavity to resonate Raman scattered radiation that is scattered by an analyte.

A system is disclosed for detecting a signal field from a sample volume. The system includes a source system and an optical fiber system. The source system provides a first electromagnetic field at a first frequency and a second electromagnetic field at a second frequency that is different from the first frequency. The optical fiber system includes at least one optical fiber for guiding the first and second electromagnetic fields to the sample volume to generate coherent radiation characteristic of molecular vibrations by non-linear interaction of the first and second fields with the sample volume. The optical fiber system also receives the signal field resulting from the coherent radiation, and guides the signal field to a detector.

The invention discloses a micro fluid control detection device based on surface-enhanced Raman scattering active substrate. The micro fluid control detection device is obtained by the method including the following steps: photoresist is coated on substrate in spinning way, prebaking, exposure, developing and fixing are sequentially carried out on the photoresist, so as to form photoresist graph in micro fluid shape; plasma dry etching is carried out on the photoresist, thus forming nano granular structure or nano fiber upright structure in vertical distribution on the substrate; the nano granular structure is a mask, anisotropic etching is carried out on the substrate, thus forming nano column on the substrate; metal nano granular layer is sputtered on the silicon nano column or nano fiber upright structure, so as to obtain surface-enhanced Raman scattering active substrate; and a silicon-PDMS double-layer structure SERS micro fluid control detection device which has no impurity interference and can be monitored in real time is formed by combining micro fluid device and processing technology thereof. The micro fluid control device not only can be used for detection of liquid analyte to be analyzed but also can be used for detection of colloid and gas analyte to be analyzed.

Apparatus and method for amplifying laser signals using segments of fibers of differing core diameters and/or differing cladding diameters to suppress amplified spontaneous emission and non-linear effects such as four-wave mixing (FWM), self-phase modulation, and stimulated Brillouin and/or Raman scattering (SBS/SRS). In some embodiments, different core sizes have different sideband spacings (spacing between the desired signal and wavelength-shifted lobes). Changing core sizes and providing phase mismatches prevent buildup of non-linear effects. Some embodiments further include a bandpass filter to remove signal other than the desired signal wavelength and/or a time gate to remove signal at times other than during the desired signal pulse. Some embodiments include photonic-crystal structures to define the core for the signal and/or the inner cladding for the pump. Some embodiments include an inner glass cladding to confine the signal in the core and an outer glass cladding to confine pump light in the inner cladding.

The present invention provides an apparatus for measurement of Raman scattered radiation comprising. The apparatus comprises at least one source of electromagnetic radiation for producing an electromagnetic radiation beam characterized by a narrow spectral width, an integrating cavity having an interior and an exterior, wherein a sample is placed in said interior. The integrating cavity further having at least one port for insertion of the sample in the interior and for transmission of the electromagnetic radiation into and out from the interior, the at least one port extending from the exterior to said interior of said integrating cavity. The integrating cavity also comprises a first optical element for transmitting the electromagnetic radiation into the interior of the integrating cavity through the at least one port, and a second optical element for collecting Raman scattered electromagnetic radiation from the sample through the at least one port. The apparatus also comprises a spectrum analyzer for determining spectral composition of the Raman scattered electromagnetic radiation, a detector for measuring the Raman scattered electromagnetic radiation; and a system for determining concentration of at least one chemical compound from the measured Raman scattered electromagnetic radiation. The apparatus may also comprise a radiation expanding element. A method for measuring the concentration of one or more chemical compounds in a sample using Raman scattering is also provided.

New and improved applications of Raman Scattering are disclosed. These applications may be implemented with or without using an enhanced nano-structured surface that is trademarked as the RamanNanoChip™ disclosed in a pending patent. As a RamanNanoChip™ provides much higher sensitivity in SERS compared with conventional enhance surface, broader scopes of applications are now enabled and can be practically implemented as now disclosed in this application. Furthermore, a wide range of applications is achievable as new and improved Raman sensing applications. By applying the analysis of Raman scattering spectrum, applications can be carried out to identify unknown chemical compositions to perform the tasks of homeland security; food, drug and drinking materials safety; early disease diagnosis; environmental monitoring; industrial process monitoring, precious metal and gem authentications, etc.

Nanoparticles comprising surface-enhanced Raman scattering (SERS) reporter molecules of the formula A-Y and methods of their use are disclosed, wherein A is selected from the group consisting of:

wherein X₁ is CR₄ or N; and Y is selected from the group consisting of:

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.

A spectroscopic method, preferably Raman scattering, is used to rapidly determine the general health or stress status of living plants and plant products, including agricultural crops, forests, and harvested fruits and vegetables. In the preferred embodiments, carotenoid levels are used to provide an indication of oxidative deterioration. Based upon the results of the analysis, further action may or may not be taken, for example, in terms of choosing, picking, harvesting or sorting the agricultural product in accordance with the carotenoid level. Concentration levels of an analyte substance can be determined relative to an external standard, to each other, or relative to another substance in the item being analyzed. Carotenoids such as lycopene, beta-carotene, lutein, violaxanthin, neoxanthin, antheraxanthin, and zeaxanthin are determined according to the invention, through other plant components may be analyzed such as other terpenes, polyenes, chlorophyll, proteins, starches, sugars, overall nitrogen levels, flavonoids, and vitamins. The hardware associated with the invention may be field portable or mounted on a piece of equipment such as a harvester or sorter.

The microscope has a first pulsed laser generating means, a second pulsed laser generating means, an irradiation means to irradiate to a specimen by composing the first pulse light and the second pulse light, a coherent Raman scattering light extraction means for extracting only the coherent Raman scattering light from light emanated from the specimen irradiated, an extraction means for extracting only the multiphoton excitation fluorescence, an extraction means for extracting only the second harmonic wave, a detection means for detecting the extracted coherent Raman scattering light, and a detection means for detecting the extracted fluorescence, and a detection means for detecting the second harmonic wave via the extraction means 7. To single specimen, responding to purposes, observations of the two-photon excitation fluorescence observation, the second harmonic wave observation, and the coherent Raman scattering light observations can be carried out in parallel, or selectively.

Multiplexed lateral flow assays, related methods, and devices are disclosed which are capable of simultaneously detecting multiple analytes. The assays are preferably immunoassays and can be multiplexed spatially, spectrally, and both spatially and spectrally. Multiplexed assays are disclosed employing quantum dots for applications including the detection of human proteins and the monitoring of microorganisms relevant to water contamination. The multiplexed assays can employ one or more species of Surface Enhanced Raman Scattering nanoparticles, with one or more species having a unique Raman shift spectrum. The invention is widely adaptable to a variety of analytes such as biowarfare agents, human clinical markers, and other substances.

The invention relates to an orderly controllable surface-reinforced Raman scattering active substrate and a preparation method thereof, and belongs to the technical field of laser-Raman spectrum detection. The substrate has a structure of a periodical hexagonal plum-blossom silver nano island, wherein the silver nano island is semispherical; the diameter of the silver nano island is approximately between 45 and 55 nanometers; and the central aperture of each hexagonal plum-blossom structure is adjustable within the spacing approximately between 10 and 90 nanometers. The method for preparing the surface-reinforced Raman scattering substrate with the orderly and controllable silver nano island structure comprises: preparing a porous alumina template; and utilizing magnetron sputtering to spray silver on the surface of the template to obtain the reinforced substrate. The substrate has the advantages of high surface-reinforced Raman scattering effect, orderly and controllable structure, good repeatability, high stability, low technical cost, simple operation and the like.

Disclosed are nanostructured gold films which may be produced by solution-phase depositions of gold ions onto a variety of surfaces. The resulting plasmonic gold films are used for enhanced spectroscopic-based immunoassays in multiplexed microarray format with detection mechanisms based on either surface-enhanced Raman scattering or near-infrared fluorescence enhancement. The preparation of the films and subsequent modifications of the gold film surfaces afford increased sensitivity for various microarrays. The films are discontinuous, forming gold “islands.” Sensitivity, size, shape, and density of the nanoscopic gold islands comprising the discontinuous nanostructured gold film are controlled to enhance the intensity of Raman scattering and fluorescence in the near-infrared, allowing for improved measurements in clinical diagnostic or biomedical research applications.

The invention discloses a silver nanodendrite surface enhanced Raman scattering (SERS) substrate, and a preparation method and application thereof, relating to the technical field of nanomaterial science and Raman detection. The SERS active substrate is of silver dendrites which are distributed evenly, and the three-dimensional sizes of dendrites are adjustable. The preparation method of the invention is characterized in that the silver nanodendrites are electrically deposited on commercially available ITO (Indium-doped Tin Oxide) conductive glass by adopting a constant current deposition method and using a silver nitrate solution as electrolyte without adding any other auxiliary. The preparation method of the invention has the advantages of simple, convenient fast (30s) preparation process, low cost, small current and low voltage, and the silver dendrites can be transferred to any substrate (paper, other metal sheets or plastic sheets). The substrate obtained by the method disclosed by the invention has high stability and ordered and controllable structure, and exhibits quite high sensitivity in Raman spectrum detection.

The invention provides a preparation method of an active radical with a surface-enhanced Raman scattering (SERS) effect, belongs to the technical field of spectrum detection, and relates to the preparation technology of the SERS active radical, which is rapid, has high sensitivity and performs a low trace detection function. The preparation method is characterized in that firstly, a nano porous silicon columnar array with a large specific surface area is prepared by utilizing a hydrothermal etching technology; afterwards, a nanowire structure of an II-VI group compound semiconductor (such as zinc oxide, titanium dioxide, cadmium sulfide, cadmium selenide, cadmium telluride, and the like) by utilizing a chemical vapor deposition method; and finally, nano particles of precious metal (such as gold, silver, copper and the like) are finally prepared on the nanowire structure by using a chemical reduction method, so as to obtain an active radical material. The preparation method has a wide application prospect in the aspects of clinical biomolecular fast recognition, trace chemical substance detection, biological sample analysis, and the like. The preparation method has the advantages that the preparation process of each material is simple, the condition is mild and the repetition rate reaches 100 percent.

Raman molecular imaging is used to differentiate between normal and diseased cells or tissue. For instance benign and malignant lesions of bladder and other tissues can be distinguished, including epithelial tissues such as lung, prostate, kidney, breast, and colon, and non-epithelial tissues, such as bone marrow and brain. Raman scattering data relevant to the disease state of cells or tissue can be combined with visual image data to produce hybrid images which depict both a magnified view of the cellular structures and information relating to the disease state of the individual cells in the field of view.

In one aspect of the present invention, an apparatus includes a first light source for generating a broadband light, and a second light source for generating a monochromatic light, a beamsplitter optically coupled to the first light source for receiving the broadband light and splitting the received broadband light into a reference light and a sample light, a reference arm optically coupled to the beamsplitter for receiving the reference light and returning the received reference light into the beamsplitter, and a sample arm optically coupled to the beamsplitter and the second light source for combining the sample light and the monochromatic light, delivering the combined sample and monochromatic light to the target of interest, collecting a backscattering light and a Raman scattering light that are generated from interaction of the sample light and the monochromatic light with the target of interest, respectively, returning the backscattering light into the beamsplitter so as to generate an interference signal between the returned backscattering light and the returned reference light in the beamsplitter, and directing the Raman scattering light in an output optical path, and a single detector optically coupled to the beamsplitter for collecting the interference signal.

The invention discloses a sensing device of optical fiber distribution type temperature and stress and mainly comprises a light source module (1), a frequency discriminator module (2), and a thermo tank module (3), which are all connected with one another by polarization-preserving fiber. The invention is a direct detection method which is based on optical fiber Raman scattering used as a carrier wave of temperature information, brillouin scattering used as a carrier wave of stress, rayleigh scattering used for measuring relative frequency of a outgoing laser beam to a frequency discriminator and Fabry-Perot etalon used for discriminating frequency and distributing sensing temperature and stress. The invention has the advantages of simple structure, fine stability, avoidance of outgoing power of the light source during coherent detection, outgoing frequency of the light source. Instability of acoustic modulation or electro-optic modulation frequency is directly referred to measure errors and the direct detection technology of the frequency discrimination is not sensitive to frequency drift of the light source and fluctuation of signal intensity.

A method of obtaining a distributed measurement comprises deploying an optical fibre in a measurement region of interest, and launching into it a first optical signal at a first wavelength λ₀ and a high power level, a second optical signal at a second wavelength λ₋₁, and a third optical signal at the first wavelength λ₀ and a low power level. These optical signals generate backscattered light at the second wavelength λ₋₁ arising from Raman scattering of the first optical signal which is indicative of a parameter to be measured, at the first wavelength λ₀ arising from Rayleigh scattering of the first optical signal, at the second wavelength λ₋₁ arising from Rayleigh scattering of the second optical signal, and at the first wavelength λ₀ arising from Rayleigh scattering of the third optical signal. The backscattered light is detected to generate four output signals, and a final output signal is derived by normalising the Raman scattering signal to a function derived from the three Rayleigh scattering signals, which removes the effects of wavelength-dependent and nonlinear loss.

A system for detecting controlled substances on an object including at least one laser for illuminating at least part of an object with laser energy and either a second harmonic detector or a luminescence controlled substance detector, or both. Additionally, a system also including a Raman scattering controlled substance detector is disclosed.

The invention relates to a preparation method for a graphene-based surface enhanced Raman scattering (SERS) probe. Compared with the traditional SERS probe using metal nanoparticle sol as an enhanced substrate, the SERS probe adopts a graphene-metal nanoparticle composite structure as a surface enhanced Raman substrate, wherein the SERS signal is obviously enhanced and the metal nanoparticles on the surface of the graphene are uniform and controllable. The main reason is that as gold nanoparticles exist on the surface of a silicon wafer dispersively, sufficient 'hot points' cannot be generated among the particles, and the gold nanoparticles gather on the surface of graphene oxide, the electromagnetic enhanced effect is achieved and stronger SERS effect is achieved.

The invention discloses a detection method suitable for a sensing device of optical fiber distribution type temperature and stress. The sensing device of the optical fiber distribution type temperature and stress mainly comprises a light source module (1), a frequency discriminator module (2), and a thermo tank module (3), which are all connected with one another by polarization-preserving fiber. The detection method of the invention is a direct detection method which is based on optical fiber Raman scattering used as a carrier wave of temperature information, brillouin scattering used as a carrier wave of stress, rayleigh scattering used for measuring the relative frequency of a outgoing laser beam to the frequency discriminator and Fabry-Perot etalon used for discriminating frequency and distributing sensing temperature and stress. The invention has the advantages of simple structure, fine stability, avoidance of outgoing power of the light source during coherent detection, and outgoing frequency of the light source. Instability of acoustic modulation or electro-optic modulation frequency is directly referred to measure errors and the direct detection technology of frequency discrimination is not sensitive to the frequency drift of the light source and the fluctuation of signal intensity.

Surface enhanced Raman Scattering (SERS) and related modalities offer greatly enhanced sensitivity and selectivity for detection of molecular species through the excitation of plasmon modes and their coupling to molecular vibrational modes. One of the chief obstacles to widespread application is the availability of suitable nanostructured materials that exhibit strong enhancement of Raman scattering, are inexpensive to fabricate, and are reproducible. I describe nanostructured surfaces for SERS and other photonic sensing that use semiconductor and metal surfaces fabricated using femtosecond laser processing. A noble metal film (e.g., silver or gold) is evaporated onto the resulting nanostructured surfaces for use as a substrate for SERS. These surfaces are inexpensive to produce and can have their statistical properties precisely tailored by varying the laser processing. Surfaces can be readily micropatterned and both stochastic and self-organized structures can be fabricated. This material has application to a variety of genomic, proteomic, and biosensing applications including label free applications including binding detection. Using this material, monolithic or arrayed substrates can be designed. Substrates for cell culture and microlabs incorporating microfluidics and electrochemical processing can be fabricated as well. Laser processing can be used to form channels in the substrate or a material sandwiched onto it in order to introduce reagents and drive chemical reactions. The substrate can be fabricated so application of an electric potential enables separation of materials by electrophoresis or electro-osmosis.