313 results about "Fluorescence Spectrophotometry" patented technology

An apparatus and method for medical practitioners to detect the presence of abnormal cells including cancerous and pre-cancerous cells by using a transport capsule containing an imaging apparatus including UV sources and fluorescence detectors for obtaining images and fluorescence data of biological cells and tissue. The method includes the steps of scanning biological tissue using an ultra-violet (UV) source to obtain fluorescence data, transferring fluorescence data and/or images using a radio frequency (RF) or other suitable means to a personal computer (PC) system, analyzing the image and/or fluorescence data in the PC, identifying -tissues with precancerous and cancerous cells, and optionally determining their precise location, and assessing the accuracy of the calculated fluoroscopic images.

A Raman spectrometer that employs a time-gated single photon avalanche diode array as a sensor is described. The spectrometer can also perform fluorescence spectroscopy and laser induced breakdown spectroscopy (LIBS). A laser is used to provide an excitation signal to excite a specimen of interest. A spectrometer is used to separate the various intensities over a range of wavelengths, which are then caused to impinge on the array to be recorded. The time-gated single photon avalanche diode array is triggered in synchrony with the excitation signal so as to allow time resolution of the response of the sample of interest to the excitation. The array can be time-gated to resolve signals that have shorter durations as a function of time while excluding signals that have a longer time duration. Raman and LIBS signals can be observed even from specimens that fluoresce strongly.

The invention provides a system and method utilizing, among other things, fluorescence spectroscopy in the ultraviolet portion of the electromagnetic spectrum to determine chemical species and concentrations. The basic measuring system includes optics, a spectrograph, a detector, and an energy source (“head” components), along with a computer and control electronics and power source capable of generating and detecting unique fluorescence signatures for individual and unique mixtures of chemical substances including, for example, prescribed and/or compounded medications, alcohol products, food types, synthetic drugs, narcotics, perfumes, liquids, and the like.

The present invention is directed to a method of applying radiation through an optical fiber for detecting disease within a plant or animal or imaging a particular tissue of a plant or animal. In addition, fluorescence can be detected and localized within a subject by such application of radiation through an optical fiber. The radiation is effective to promote simultaneous multiphoton excitation. The optical fibers are used alone to examine internal regions of tissue, in conjunction with an optical biopsy needle to evaluate sub-surface tissue, or with an endoscope to evaluate tissue within body cavities.

A method utilising one or more fluorogenic probes, for the detection of nitroreductase activity. The non-fluorescent probes are reduced in the presence of nitroreductase to form fluorescent derivatives that may be detected using fluorescence spectroscopy. In particular, the method may be used to detect and/or identify a plurality of nitroreductase in a single test environment

This invention discloses an Excitation Emission Matrix (EEM) fluorescence spectrometer system that uses an LED array to cause excitation emission matrix fluorescence that is imaged onto a spectrograph for sample identification and analysis. By using the LED array, the spectrograph requires only high spectroscopic resolution of about 1 to 5 nm in the fluorescence emission range and low excitation light resolution of about 14 to 73 nm in the excitation range. While individual LED optical excitation spectra may contain wavelength regions that overlap, as long as the various LEDs have different excitation wavelengths and intensities, spectral overlap does not preclude data analysis. The invention provides an EEM spectroscopy system that is not a high resolution such as a laser or lamp based excitation system, but instead uses a lower resolution, lower power LED system. The invention also provides results that are comparable to existing systems with lower component cost and lower power requirements while also optically stable, small, and easy to use.

The mechanism of the UV light-induced reaction between the indole moiety of tryptophan and chloroform, and the structure of the modified tryptophan and polypeptides including such modified tryptophan residues. The excited indole moiety, which is formed upon UV light irradiation, emits a solvated electron which initiates a series of events that yield fluorescent derivatives that have CHO group covalently bound to the indole moiety. These derivatives are herein referred to as formyltryptophan, and are relatively stable. Similar reactions are observed when 5-hydroxytryptophan, 5-fluorotryptophan, or N-methylindolacetate are used in place of tryptophan, or when other haloalkanes, such as trichloracetic acid, trichlorethanol, trichlorethane, bromoform, and iodoactetate are used in place of chloroform. The derivatives can be used in a variety of applications in fluorescence spectroscopy, and for nuclear magnetic resonance, X-ray crystallography, infra-red spectroscopy, circular dicroism and mass spectroscopy. Additionally, the UV light-induced reaction between the indole moiety of tryptophan and haloalkanes can be used to prepare derivatives of tryptophan for chemical cross-linking studies of proteins and peptides.

Polymer composite films were prepared by solvent casting suspensions of quantum dots (QDs) in cellulose triacetate (CTA) solution. The films were robust and possessed the optical properties characteristic of QDs. Transmission electron microscopy (TEM) images of the films revealed that the QDs were well dispersed within the CTA film matrix. The selective alkaline hydrolysis of QD/CTA films in 0.1N NaOH over 24 hours resulted in the surface conversion of CTA to regenerated cellulose. Optical properties of the films were probed both before and after the hydrolysis reaction using fluorescence spectroscopy, and were found generally unaltered. The cellulose surfaces of the alkaline treated films allow for facile incorporation of the films into paper sheets.

A protein transduction method for efficiently delivery of exogenous proteins into mammalian cells is invented, which has the capability of targeting different cellular compartments and protection from degradation of the delivered proteins from cellular proteases. A composition for treat proteins has cation reagents, lipids and enhancers in a carrier. The method can be used in a number of ways including: production of large quantities of properly folded, post-translationally modified proteins using mammalian cell machinery, a in-cell fluorescence spectroscopy and imaging using small molecule fluorophores and a in-cell NMR spectroscopy using living mammalian cells. The method permits cell biology at atomic resolution that is physiologically and pathological relevant and permits protein therapy to treat human diseases. The method can also be used to deliver exogenous protein inside mammalian cells, wherein the exogenous proteins follow a similar secretion pathway as that of the endogenous protein.

Spectroscopic chemical analysis methods and apparatus are disclosed which employ deep ultraviolet (e.g. in the 200 nm to 300 nm spectral range) electron beam pumped wide bandgap semiconductor lasers, incoherent wide bandgap semiconductor light emitting devices, and hollow cathode metal ion lasers to perform non-contact, non-invasive detection of unknown chemical analytes. These deep ultraviolet sources enable dramatic size, weight and power consumption reductions of chemical analysis instruments. Chemical analysis instruments employed in some embodiments include capillary and gel plane electrophoresis, capillary electrochromatography, high performance liquid chromatography, flow cytometry, flow cells for liquids and aerosols, and surface detection instruments. In some embodiments, Raman spectroscopic detection methods and apparatus use ultra-narrow-band angle tuning filters, acousto-optic tuning filters, and temperature tuned filters to enable ultra-miniature analyzers for chemical identification. In some embodiments Raman analysis is conducted simultaneously with native fluorescence spectroscopy to provide high levels of sensitivity and specificity in the same instrument.

In one aspect, the present invention relates to a process for intra-operatively providing anatomical guidance in endocrine surgery. In one embodiment, the process includes the steps of illuminating tissues in the neck area of a living subject with a beam of light having a predetermined wavelength, obtaining Raman data from light scattered from the illuminated tissues, finding Raman signatures corresponding to thyroid or parathyroid tissues from the obtained Raman data, and identifying the thyroid or parathyroid tissues from the corresponding Raman signatures.

The invention discloses an integrating sphere device for optical measurement, relates to the technical field of optical measurement and aims to solve the problems of poor symmetry, ineffective heating control of a light source and non-adjustable flux of a sampling port existing in the conventional integrating sphere device structure. A first half integrating sphere shell and a second half integrating sphere shell of the device are fastened together to form a hollow sphere shell; a central light barrier is fixed at the central position of a joint surface of the first half integrating sphere shell and the second half integrating sphere shell; a joint between an adjustable light source and the first half integrating sphere shell is provided with a sampling hole; a slit device is fixed between the adjustable light source and the sampling hole; a stray light eliminating device is fixed on the second half integrating sphere shell through a screw thread; a position on which the second half integrating sphere shell is fixed with the stray light eliminating device is provided with a light emitting hole; and a detection hole is formed on the lower part of the light emitting hole on the second half integrating sphere shell. The integrating sphere device is suitable for fields such as the measurement of the radiation quantity of a light-emitting diode (LED) or various lamps, color measurement, fluorescence spectroscopy and the like.

The invention discloses a method for fast optical tracking of a single molecule and a device, and relates to a technology for detecting single-molecule fluorescence spectroscopy and signal processing.The method uses the single-photon detection technology for detecting molecular fluorescence, analyzes the detected position with strongest fluorescence strength for determining the position of the single molecule, controls a nano-translation stage by feedback of a computer for tracking the position of the molecule and realizes the fast tracking of the motion trajectory of the molecule. The methodadopts the low-frequency sine wave modulation for triggering a laser signal of a single-molecule sample, thereby improving the signal-to-noise ratio. Compared with the prior art, the method adopts the single-photon detection technology, thereby being capable of determining and fast tracking the position of the single molecule in a relatively fine manner; the central position of the optoelectronicfeedback control nano-translation stage is changed along with the position of the single molecule, thereby being capable of reflecting the motion trajectory of the single molecule in a real-time manner; and the use of the modulation and demodulation technology can effectively suppresses the impacts of background noise on the detection of a fluorescence signal of the single molecule.

The method for discriminating between benign and malignant prostate tumors relates to analyzing samples of blood, urine and tissue by fluorescence spectroscopy in order to detect the presence of naturally occurring molecules in the fluids and tissue that serve as biomarkers indicative of cancer in the human body. The analysis can be carried out based on fluorescence emission spectra, fluorescence excitation spectra and synchronous (emission and excitation) spectra of bio-samples. The detection, diagnosis, and follow-up and also discrimination between malignant and benign prostate tumors may be made by comparison of ratios of fluorescence emissions and/or excitation intensities of tryptophan, tyrosine, elastin, collagen, bile pigments, NADH, flavins and various species of porphyrins.

The invention provides a loaded double-metal hydrogenation catalyst, and a preparation method and application thereof. The catalyst comprises a gamma-Al2O3-contained carrier and active metal components loaded on the gamma-Al2O3-contained carrier, wherein the active metal components comprise a group-VIB metal component and a group-VIII metal component which have the following characteristics: through the analysis of an X-ray photoelectron spectroscopy, the mol ratio of the group-VIB metal atom to the Al atom on the surface of the catalyst is measured to be 0.11 to 0.25, and the mol ratio of the group-VIII metal atom to the Al atom on the surface of the catalyst is measured to be 0.01 to 0.10; and through the analysis of an X-ray fluorescence spectroscopy, the mol ratio of the group-VIII metal atom to the group-VIB metal atom in the catalyst is measured to be 0.2 to 1. The loaded double-metal hydrogenation catalyst prepared by using the method provided by the invention has good dispersibility, active-centre accessibility and structural stability, significantly improves hydrodesulphurization property of the catalyst, and has good industrial application prospects.

The invention discloses a device and a method for on-line detection of sulfide concentrations in a water sample by utilization of fluorescence spectrophotometry. The device comprises a sample acidification component, a gas extraction component, a solution absorption component, a gas supply component, a fluorescence detection component, and the like. The invention further provides the method for on-line sulfide detection by using the device. The device and the method have advantages of stable and reliable detection results, rapid and accurate detection processes, good reproducibility, stable and reliable results, capability of achieving automatic detection processes, capability of continuously real-time on-line monitoring for a long time and capability of saving human and material resources.