74 results about "Light scatter measurement" patented technology

A novel reagent system for use with automated and semi-automated hematology analyzers including an essentially isotonic blood diluting reagent, a blood cell lysing and hemoglobin conversion reagent, and a second lysing reagent for differentiating white blood cells into classes by size and functional characteristics. The diluent reagent enhances properties for counting and sizing blood specimens, while stabilizing cellular volume and cellular integrity for many hours. The blood cell lysing reagent removes red blood cells and enables subsequent enumeration of white blood cells and simultaneous determination of hemoglobin without use of the toxic cyanide anion. The third lysing reagent and a companion quenching differentiates blood cells into classes by size and functional characteristics, based on d.c. impedance volume, conductivity/opacity and light scatter measurements. The companion quenching reagent adjusts pH and conductivity of the final measurement solution to match the analyzer system requirements. Novel methods for use of the reagents with automated and semi-automated hematology analyzers are also provided.</PTEXT>

Methods are provided for measurement of nucleated red blood cells in a blood sample. The methods include exposing a blood cell sample to a reagent system to lyse mature red blood cells, subsequently analyzing nucleated red blood cells in a flow cell by axial light loss, DC impedance, and medium angle light scatter measurements; by axial light loss, low angle light scatter, and medium angle light scatter measurements; or by axial light loss, DC impedance, low angle light scatter, and medium angle light scatter measurements; and then differentiating nucleated red blood cells from other cell types by using measured signals and/or functions thereof.

The invention relates to a method for measuring the mass concentration of a particulate matter. A processor controls a sampling pump so that airflow enters from a particulate matter collecting unit, atmospheric particulate matter information is acquired, whether an instrument needs to be calibrated is judged, a beta-ray calibration module is started to calibrate the parameter values of a light scattering measurement module if calibration is needed, and the light scattering measurement module is turned on after the parameters are calibrated; and if calibration is not needed, the light scattering measurement module directly carries out measurement. By combining a light scattering method for measuring the concentration of the particulate matter with a beta-ray method, the measurement is accurate and data are directly read on line in real time; the beta-ray calibration module and the light scattering measurement module share one gas path, so as to ensure that various conditions in the calibration process are consistent and reduce error factors; and the parameters of the light scattering measurement module are calibrated by using the beta-ray calibration module when the measurement environment is changed, and the light scattering measurement module is separately utilized to measure the concentration of the particulate matter when the measurement environment is not changed.

System and method for detecting and counting bacteria suspended in a biological fluid by means of light scattering measurements is provided. In accordance with the method of the invention the level of signal to noise of the measured intensities of light scattered by a sample of the biological fluid is significantly enhanced for forwardly scattered light within a range of scattering angles which are smaller compared to a predefined maximal scattering angle. The system of the invention includes a cuvette adapted to contain a sample of the biological fluid whose sidewalls and windows are suitably constructed and arranged to significantly reduce the level of reflected light obscuring the scattering patterns measured within the range of scattering angles considered.

A method for the detection of bacteria in aqueous fluids in the form of solutions, emulsions and or suspensions, such as drinking water, liquid food and drinks and biological fluids such as urine, spinal and/or amniotic fluids and serums by measurement of light scattering The fluid suspected of containing bacteria is filtered, first to exclude particles of sizes larger than the size of the expected bacteria. Other filtration methods are used in addition to exclude different constituents of the examined fluid. Ion exchange chromatography is such a method. The verification of bacterial contamination and the calculation of its level is performed by matching measured scattering profiles with pre-stored calibrated scattering profiles. A system for carrying out the measurements including cuvette units suited for light scattering measurements is provided.

The invention discloses a method for synchronous measurement of the optical constant and particle size distribution of spherical particles based on a multi-angle light scattering-transmission process, relates to the technical field of participating medium radiation property measurement and is aimed at solving the problems of great error of experimental measurement value and relatively weak measurement signal in participating medium radiation parameter measurement based on inverse problem solving. The method comprises the following steps: irradiating the surface of a particle system sample by using continuous steady-state laser; arranging optical detectors on different scattering-angle positions; measuring the scattering optical signal intensity and hemispherical transmission signal of the steady-state laser of different angles; and obtaining the optical constant of the spherical particles and the particle size distribution of the particle system in combination with the signals and through the inverse problem solving technology. The method disclosed by the invention is suitable for synchronous measurement of the optical constant and particle size distribution of spherical particles based on a multi-angle light scattering-transmission process.

A cuvette for use with light scattering detectors is disclosed. A trough or moat within the cuvette can be filled with solvent which is not in fluid contact with the sample to be measured. This solvent moat creates saturated vapor pressure in the chamber preventing evaporation from the sample when the cuvette is capped. The cuvette itself may be made of an inexpensive polymer which can be polished to high optical quality while still being moldable in complex forms capable of enabling further utility, such as extra griping surfaces, identification tabs allowing the detection instrument to determine the cuvette model, and various sample chamber forms. The novel cuvette may have extremely small sample volumes, while allowing significant overfill of the measurement chamber, improving ease of sample loading. The polymers used may be relatively inexpensive, and therefore the cuvette can generally be discarded after a single use.

The invention discloses a number concentration measurement device of atmospheric ultrafine particles. The number concentration measurement device comprises an atmospheric airflow channel, a sample gas flow channel, a shell gas flow channel, a gas inlet device, a saturated solution device, a condensing device and an optical detection device. According to the number concentration measurement device, on the basis of a condensation nucleus theory and a light scattering measurement theory, i.e. shell gas flow passes through steam of a heated saturated solution and then is mixed with the air flow of the atmospheric ultrafine particles, the ultrafine particles pass through the condensing device and then are condensed to grow up, and then a light scattering technique is used for measuring the particles which are condensed to grow up, so as to obtain a number concentration value of the particles. By using the shell gas flow designed in the number concentration measurement device, the loss of sample gas flow particles can be reduced, and the condensation nucleus efficiency of the ultrafine particles can be effectively improved. The number concentration measurement device has the advantages of small and compact structure and high applicability, and the number concentration of the particles with a particle diameter range between 3 nm to 5 microns can be measured.

The various embodiments herein provide for the engineered multimodal super paramagnetic iron oxide nanoparticles (SPIONs) with a fluorescent dye. The SPIONs comprise fluorescent polymer dye arranged in a gap between a SPION core and a gold shell. The SPIONS are provided with a gold coating. The gap is made up of a polymeric molecule such as 6-arm anthracene terminated. The core of the nanoparticle is made up of a magnetic metal oxide. The method for synthesizing SPIONs involves preparing carboxyl-dextran complex and the SPIONS. The SPIONs are coated with carboxyl-dextran complex. The coated SPIONs coated are subjected to fluorescent polymer and gold nano shell coating. The prepared SPIONs are characterized by light scattering measurement and magnetization measurements.

The present invention features methods and devices for microorganisms through detecting Mie light scattering from immunoagglutinated beads. The methods feature providing a first bead suspension with antibody specific for the microorganism conjugated to beads; mixing the first bead suspension with a sample to form a first mixture; irradiating the first mixture with first incident light; detecting forward light scattering at a first angle with respect to the first incident light, where the first angle being between about 30 to 60 degrees; determining l from the light scattering; providing a second bead suspension with no antibody and simultaneously measuring l₀ in a similar manner; comparing l with l₀. All light scattering measurements may be made in a two-well slide or a Y-channel microfluidic device. Samples, for example food samples (e.g., vegetable samples), may be prepared in a variety of ways. A vegetable sample may be chopped up and added to a buffer. In some embodiments, the sample is then filtered with a common cloth or tissue component. The present invention also features devices (or apparatuses) for detecting a microorganism in a sample. The apparatuses may be a large-scale device or a small-scale device. The large-scale device may consist of a portable spectrometer, light source, optical fibers, and adjustable positioning stages, in addition to, for example, a two-well slide or a microfluidic device. The small-scale device is made portable by using, for example, light-emitting diodes, avalanche photodiodes, an op-amp circuit, Arduino microcontroller board, an LCD display, and small batteries, in addition to, for example, a two-well slide or a microfluidic device. Therefore, the invention is adaptable for detecting microorganisms in vegetable sample preparations. Still further, the invention may be operated on a small-scale, for example, for use by workers in agriculture fields or food factories.

A light scattering measurement system for particulate matters comprises a scattering measurement chamber, a light source, a scattering light detector, a data acquisition and analysis module, a light source polarizing device and a plurality of scattering light polarization analyzers. The scattering measurement chamber includes a light channel and a particulate matter sample injecting channel, a center line of the light channel and a center line of the particulate matter sample injecting channel intersect at an intersection point. The light source is mounted on one side of the scattering measurement chamber. The light source polarizing device is positioned between the scattering measurement chamber and the light source. The multiple scattering light polarization analyzers are arranged at positions differently angled with the center line of the light channel from the intersection point as a start point; the scattering light detector is arranged in correspondence with the multiple scattering light polarization analyzers and used for receiving light from the multiple scattering light polarization analyzers. The invention also provides a light scattering measurement method for particulate matters. The particulate matters are measured based on a particulate matter multi-angle scattering method, and particle sizes and attributes of the particulate matters can be determined.

The invention relates to a polarized light scattering measurement system and method based on magneto-optic modulation. Coherent light sent out by a laser is changed to linear polarized light through a polarizer, and the linear polarized light is focused into a sample matching tank through a focusing lens. Scattered light coming out from the sample matching tank passes through an expanded beam collimating lens to reduce a divergence angle of the scattered light and collimate the diameter of an outgoing beam, and then the scattered light passes through a Faraday coil, a polarization analyzer and an expanded beam lens in sequence to obtain linear polarized light with periodic changes which can be received by a photomultiplier tube after passing through an aperture diaphragm capable of limiting a photosensitive area, signals are sent into a phase-locked amplifier by the photomultiplier tube to filter and remove external noise and white noise inside equipment, and then sent into a sampling integrator and a computer for sampling integration and digital average to obtain the particle size distribution. Compared with the prior art, the polarized light scattering measurement system and method based on the magneto-optic modulation can be used for low-intensity laser measurement without interference or damage to a sample, can be used for quickly and accurately measuring the nanoparticle size, suppressing the noise to the maximum extent and improving the measurement accuracy to enable the system to be suitable to be used in various environments.

The invention relates to an improved method and apparatus for measuring the scattered light signals from a liquid sample. A sample cell for making light scattering measurements, incorporating an exterior surface acting as both a lateral and vertical lens, is described. This unique structure permits greatly improved measurement of the light scattered by molecules and particles suspended in a fluid contained therein or flowing therethrough while illuminated by a fine light beam incident thereon. The resultant lensed structure of the cell, when integrated into a scattered light photometer and combined with suitable apertures before each scattered light collecting detector, reduces significantly stray light from entering each such detector.

An apparatus for measuring the light scattering properties of a sample in a liquid medium, wherein the liquid medium with the sample is illuminated by a laser beam in a measuring cell transversely to the direction of filling the liquid medium in the measuring cell or transversely to the flow direction of the liquid medium within the measuring cell, comprising a laser, a cylindrical measuring cell, a first inner aperture system, a second outer aperture system and at least two detectors, wherein the detectors are arranged outside of the second outer aperture system so that they collect the light scattered on the sample within set, different angle ranges, wherein the first inner aperture system and the second outer aperture system are formed and arranged circularly and concentrically around the axis of the measuring cell. Use of the apparatus and a method that makes use of the apparatus are also disclosed.

The present invention relates to a disposable cartridge for fluid analysis. A disposable blood analysis cartridge may include a sample collection reservoir, an absorbance measurement channel, and an optical light scattering measurement channel. One or more valves may be disposed between the sample collection reservoir and the absorbance measurement channel and/or the optical light scattering measurement channel. A negative pressure may be applied to the cartridge to pull sample from the sample collection reservoir through the one or more valves and into the absorbance measurement channel and/or the optical light scattering measurement channel. Once the sample is pulled into the absorbance measurement channel and/or the optical light scattering measurement channel, the one or more valves may be closed. With the one or more valves closed, and in some cases, a pusher fluid may be provided to push the fluid sample to other regions of the disposable fluid blood analysis cartridge.

The invention discloses a synchronous particle and gas concentration measurement device and method based on an infrared light modulation technology. According to the method, a light scattering measurement light path is coupled with a wavelength modulation measurement light path, so that synchronous concentration measurement of low-concentration particles and gas is realized. According to the method, there is no need to additionally consider low-frequency noise such as background dark current of a detector, so that the signal-to-noise ratio of the concentration measurement of the low-concentration particles and gas is effectively increased; the sensitivity is higher; the limit to existing concentration measurement of particles and gas is lowered. Therefore, the method has an important application value in realization of synchronous online monitoring of to-be-detected particles and gas in a coal-fired power plant with ultra-low emission demands.