5635 results about "Fluorescence intensity" patented technology

An active CMOS biosensor chip for fluorescent-based detection is provided that enables time-gated, time-resolved fluorescence spectroscopy. In one embodiment, analytes are loaded with fluorophores that are bound to probe molecules immobilized on the surface of the chip. Photodiodes and other circuitry in the chip are used to measure the fluorescent intensity of the fluorophore at different times. These measurements are then averaged to generate a representation of the transient fluorescent decay response unique to the fluorophores. In addition to its low-cost, compact form, the biosensor chip provides capabilities beyond those of macroscopic instrumentation by enabling time-gated operation for background rejection, easing requirements on optical filters, and by characterizing fluorescence lifetime, allowing for a more detailed characterization of fluorophore labels and their environment. The biosensor chip can be used for a variety of applications including biological, medical, in-the-field applications, and fluorescent lifetime imaging applications.

Samples of materials used in industrial processes are analyzed to determine the concentration of certain materials of interest. The quantitative analysis of samples for these materials is provided without the need for manual methods such as titration. Indicators such as fluorescent dyes for which the intensity of fluorescence is indicative of the concentration of a material of interest are used. The dyes are made to fluoresce by means of a light source, and a photomultiplier or other detector capable of measuring light intensity detects the resulting fluorescence. The intensity of fluorescence in the sample is compared to the intensities of fluorescence produced by samples with known concentrations of the material of interest to determine the concentration of the material of interest of the sample.

Fluorescence spectral data acquired from tissues in vivo or in vitro is processed in accordance with a multivariate statistical method to achieve the ability to probabilistically classify tissue in a diagnostically useful manner, such as by histopathological classification. The apparatus includes a controllable illumination device for emitting electromagnetic radiation selected to cause tissue to produce a fluorescence intensity spectrum. Also included are an optical system for applying the plurality of radiation wavelengths to a tissue sample, and a fluorescence intensity spectrum detecting device for detecting an intensity of fluorescence spectra emitted by the sample as a result of illumination by the controllable illumination device. The system also include a data processor, connected to the detecting device, for analyzing detected fluorescence spectra to calculate a probability that the sample belongs in a particular classification. The data processor analyzes the detected fluorescence spectra using a multivariate statistical method. The five primary steps involved in the multivariate statistical method are (i) preprocessing of spectral data from each patient to account for inter-patient variation, (ii) partitioning of the preprocessed spectral data from all patients into calibration and prediction sets, (iii) dimension reduction of the preprocessed spectra in the calibration set using principal component analysis, (iv) selection of the diagnostically most useful principal components using a two-sided unpaired student's t-test and (v) development of an optimal classification scheme based on logistic discrimination using the diagnostically useful principal component scores of the calibration set as inputs.

This disclosure concerns a cytometry system including a handling system that presents single cells to at least one quantum cascade laser (QCL) source. The QCL laser source configured to deliver light to a cell within the cells in order to induce resonant mid-infrared absorption by one or more analytes of the cell. The system includes a laser source that excites at least one fluorophore present in the cell or on the surface of the cell and a fluorescence detector that measures the fluorescence intensity of the fluorophore. A mid-infrared detection facility detects the transmitted mid-infrared wavelength light, wherein the transmitted mid-infrared wavelength light and the fluorescence intensity are used to identify at least one cell characteristic.