Abstract:
Systems and methods for analyzing multiple components of a fluid sample are provided. In certain embodiments, a system can include an analyte detection system configured to measure first analyte data in a first component of a fluid sample received from a patient and measure second analyte data in a second component of a fluid sample. In some embodiments, one or more portions of an optical system is movable with respect to other portions of the system in order to optically and/or electrochemically analyze multiple components of a fluid sample. In other embodiments, optical and/or electrochemical analysis can be performed simultaneously on multiple components of a fluid sample. In some embodiments, a first analyte can be measured in a sample (e.g., whole blood) before the sample is separated into its components (e.g., plasma, red blood cells, etc.), and a second analyte can be measured in a component of the sample after separation.
Abstract:
Concentrations of a target analyte in a gas mixture containing one or more background analytes having potentially interfering spectral absorption features can be calculated by compensating for background analyte absorption at a target wavelength used to quantify the target analyte. Absorption can be measured at a reference wavelength chosen to quantify the concentration of the background analyte. Using a background gas adjustment factor or function, the absorption measured at the reference wavelength can be used to calculate absorption due to the background analyte at the target wavelength and thereby compensate for this background absorption to more accurately calculate the target analyte concentration in real or near real time. Additional background analytes can optionally be compensated for by using one or more additional reference wavelengths.
Abstract:
A method and apparatus for interfacing a plurality of gas measurement systems, including a mainstream and a sidestream gas measurement system, to a host system via an interface unit. The present invention also pertains to a sidestream gas measurement system that output signals emulating the signals output by a mainstream gas measurement system or portion thereof, so that the sidestream gas measurement system can seamlessly communicate with a host system configured to communicate with a mainstream gas measurement system or a portion thereof.
Abstract:
The invention provides a method for identifying the impacts of interfering effects on experimental data. In particular, a method is described for identifying the impacts of unwanted auto-fluorescence, fluorescence quenching, and deterioration of a fluorescent sample under study on the collected experimental data. The data are analyzed whether or not said data fulfill certain criteria with respect to a threshold which is indicative for said interfering effect.
Abstract:
A concentration of a detector gas in a measuring gas containing an interfering gas is measured. A zero gas that is free of the detector gas and/or a test gas having a known concentration of the detector gas are supplied to an analyzer such as a non-dispersive infrared (NDIR) gas analyzer. Interfering gas is added to the measuring gas, the zero gas, and in some instances, to the test gas to an extent which allows the interfering gas to have a same concentration in each case.
Abstract:
A dual path analyzer and a single path analyzer are disclosed, each for determining the concentration of one or more gaseous components in a mixture of gases. The preferred analyzer is a single path instrument which includes a source of infrared energy, a detector for the energy, a sample cell for the gas mixture positioned between the source and detector, and a filter wheel having a plurality of filters and a source blocking device positioned between the sample cell and detector for sequentially interposing the filters and the source blocking device between the source and the detector. Means are provided for amplifying the output signal of the detector and for processing the signal to provide a direct readout display which indicates the concentration of the gaseous components being analyzed. The processing electronics preferably include provision for calibrating the analyzer with clean ambient air, for compensating for background levels of radiation, and for correcting the displayed output signal for the effects of absorption band interferences between two or more gases in the gas mixture. The structure of the dual path analyzer includes a source of infrared energy, a detector for the energy, a sample cell for the gas mixture, a cell for a reference gas, and optical path means between the source and detector for sequentially directing the source energy through the sample cell, the reference cell, and through neither cell. Processing electronics similar to the single path instrument can be incorporated to compensate for background radiation and absorption band interferences.
Abstract:
A method and system for correcting the effect of intensity fluctuations of the transmitted light in an absorption spectroscopy system used for the detection or measurement of chemical species in a medium, whereby one or more modulation bursts are imposed onto a light beam that passes through the medium. This burst signal may be obtained by modulating the bias current of a tunable diode laser, and the modulation burst signal may be optimally at the second harmonic of the modulation frequency of a wavelength modulated beam to allow usage of the same signal path processing used for the spectroscopic detection of the measurand for a second harmonic detection system. The burst signal can be controlled using a smooth window function to minimise the effects of non-linear perturbations that are inherent in tunable diode laser wavelength modulation spectroscopy systems, of optical interference fringes (etalons) and of the residual light absorption by background chemical species or the measurand at the wavelength coinciding with the modulation burst.
Abstract:
A method and apparatus for interfacing a plurality of volumetric measurement systems, each of which includes a gas measurement and a flow measurement system, to a host system via an interface unit.
Abstract:
A gas analyzer system includes an optical source, an optical filter assembly, a controller, and an analyzer. The optical source generates an optical signal. The optical filter assembly includes different optical filters in which to filter the optical signal. During operation, the controller selects sequential application of each of the different optical filters in a path of the optical signal to modulate the optical signal using different frequency bands of optical energy. The modulated optical signal passes through an unknown sample. The optical analyzer analyzes the modulated optical signal after passing through the sample to detect which types of multiple different gases are present in the sample.
Abstract:
A differential absorption spectrum for a reactive gas in a gas mixture can be generated for sample absorption data by subtracting background absorption data set from the sample absorption data. The background absorption data can be characteristic of absorption characteristics of the background composition in a laser light scan range that includes a target wavelength. The differential absorption spectrum can be converted to a measured concentration of the reactive gas using calibration data. A determination can be made whether the background composition has substantially changed relative to the background absorption data, and new background absorption data can be used if the background composition has substantially changed. Related systems, apparatus, methods, and/or articles are also described.