Abstract: A process for modifying a triacylglycerol stock, such as a vegetable oil stock, to better control fluidity is provided. The process includes interesterifying the triacylglycerol stock in the presence of a basic catalyst while monitoring the absorbance of the reaction mixture. A modified triacylglycerol stock produced by partial interesterification as well as plastic spreads and water-in-oil emulsions which include the partially interesterified triacylglycerol stock are also provided.

Abstract: Methods, systems, kits for carrying out a wide variety of different assays that comprise providing a first reagent mixture which comprises a first reagent having a fluorescent label. A second reagent is introduced into the first reagent mixture to produce a second reagent mixture, where the second reagent reacts with the first reagent to produce a fluorescently labeled product having a substantially different charge than the first reagent. A polygon is introduced into at least one of the first and second reagent mixtures, and the fluorescent polarization in the second reagent mixture relative to the first reagent mixture is determined, this fluorescent polarization being indicative of the rate or extent of the reaction.

Abstract: A robust fiber optic sensor and sensing method for reliable, long-term measurement of analytes is disclosed. The sensor comprises an optical interrogation region comprising an indicator dye confined at a distal end of an optical fiber and an analyte permeable membrane enclosing the interrogation region at the distal fiber end. In a preferred embodiment, a reservoir member is provided with excess dye for continuous replenishment of the interrogation region with dye over the lifetime of the sensor. In another preferred embodiment, the reservoir member comprises an indicator support for containment of excess dye. In one preferred embodiment, a ratiometric dye is used for monitoring optical signal-to-noise and signal drift caused by sensor aging. The sensor may be configured with a variety of alternative indicator dyes and membrane materials as a specific ion sensor for analyzing dissolved analytes such as gases, cations, and anions.

Abstract: A process for detecting HIV infection, Hepatitis A, B and C, and other similar infections in a plasma sample, wherein the process involves the use of an excitation laser source to irradiate upon the plasma sample an excitation laser beam to obtain a fluorescence emission spectrum of the plasma sample. The invention uses an excitation laser wavelength of about 355 nanometers. Detection of the fluorescence is made in the wavelength range from about 380 to 600 nanometers. The resulting spectrum of the sample is compared with the spectrum of a control which is free from infection. Analysis of the parameters of the emission spectra including, but not limited to, peak intensity wavelength, amplitude at the peak intensity, area ratio of left and right portions of the emission spectra, and shifts of the peak intensity wavelength, allows determination of HIV infection, Hepatitis A, B and C, and other similar infection in the plasma.

Abstract: A biosensor based on complexes between biomolecule receptors and colloidal Au nanoparticles, and more specifically, colloid layers of receptor/Au complexes that can be used to detect biomolecule analytes through measuring of binding-induced changes in electrical resistance or surface plasmon resonance. Also disclosed is a method for detecting and analysing carrier-borne chemical compounds with Raman spectroscopy using an improved SERS substrate. Further disclosed is an improved method for detecting compounds in solvents using capillary electrophoresis in conjunction with Raman spectroscopy.

Abstract: The invention relates to a kit for the measurement of anion, cation or zwitterion availability in a medium or for the measurement of free inorganic ions in disrupted cells from plant or animal tissue. The kit comprises ion-exchange material having a measurable ion uptake potential for immobilizing available ions from the medium on the material following contact on the material with the medium or suspension. It also comprises means to remove particulate solids from the material after having contacted the medium with the material. Preferably, the ion-exchange material is cation and/or anion-exchange material in the form of rigid or flexible films, sheets, membranes or the like. The invention also relates to a method for the on-site in situ measurement of anion and/or cation availability in a solid medium and to a method for measuring free organic ions in cells from plant or animal tissue.

Abstract: An electrospray device, a liquid chromatography device and an electrosprayliquid chromatography system are disclosed. The electrospray device comprises a substrate defining a channel between an entrance orifice on an injection surface and an exit orifice on an ejection surface, a nozzle defined by a portion recessed from the ejection surface surrounding the exit orifice, and an electrode for application of an electric potential to the substrate to optimize and generate an electrospray; and, optionally, additional electrode(s) to further modify the electrospray.

Abstract: Mass flow controllers are respectively placed in the middle of a hydrogen gas tube and air tube connected to a FPD. The flow controllers are controlled to supply hydrogen and oxygen from the nozzle to achieve the optimum mixture rate of hydrogen and oxygen for combustion of each target component in a sample. Since the mixture rate of hydrogen gas and air is optimum for each target component, the quantity of light emitted by the combustion increases and detection of each target component improves.

Abstract: A method and apparatus for interrogating a target having a plurality of plasmon resonant particles (PREs) distributed in the target are disclosed. In the method, a field containing the target is illuminated, and one or more spectral emission characteristics of the light-scattering particles in the field are detected. From this data, an image of positions and spectral characteristic values in the field is constructed, allowing PREs with a selected spectral signature to be discriminated from other light-scattering entities, to provide information about the field. Also disclosed are a novel PRE composition for use in practicing the method, and a variety of diagnostic applications of the method.

Abstract: A direct assay is described using novel three-dimensional polymeric assemblies which change from a blue to red color when exposed to an analyte, in one case a flue virus. The assemblies are typically in the form of liposomes which can be maintained in a suspension, and show great intensity in their color changes. Their method of production is also described.

Abstract: A method for producing and sampling chemical agent vapor comprising the steps of placing neat chemical agent in a reservoir, purging the chemical agent in the reservoir with a dry air, and analyzing the air stream exiting the reservoir. A MINICAMS having a removable PCT may be used to analyze the air stream exiting the reservoir. The method may further comprise the steps of changing the relative humidity conditions and testing chemical agent detectors.

Abstract: A carbon-based tip for scanning probe microscopy. The tip used in microscopy to reveal chemical characteristics of a sample includes a structure of the formula:X--(L--M).sub.nin which n is 1 to 100, X is a carbon-based nanotube, L is a linking group bonded at an end of the carbon-based nanotube, and M is a molecular probe bonded to the linking group.

Abstract: This invention teaches a method to identify cellular abnormalities which are associated with disease states. The method utilizes infrared (IR) spectra of cell samples which are dried on an infrared-transparent matrix and scanned at the frequency range from 3000-950 cm.sup.-1. The identification of samples is based on establishing a reference using a representative set of spectra of normal and/or diseased specimens. During the reference assembly process, multivariate techniques such as Principal Component Analysis (PCA) and/or Partial Least Squares (PLS) are used. PCA and PLS reduce the data based on maximum variations between the spectra, and generate clusters in a multidimensional space representing the different populations. The utilization of Mahalinobis distances, or linear regression (e.g., Principle Component Regression on the reduced data from PCA) form the basis for the discrimination.

Abstract: The slope lines of the peak lines are determined for a reference specimen and a test specimen and then compared with one another to analyze peak lines independently of the background. Preferably a minimum amplitude of a slope line is established with a threshold specimen so that fluctuations with a smaller amplitude can be disregarded. This method is suitable especially for automatic analysis of blot strips.

Abstract: The present invention provides a method by which harmful trace gases in a gaseous mixture containing as such harmful halogen gases, halogenated hydrogen gases, acid gases, oxidizing gases, basic gases, organic acid gases, especially halogen gases or halogenated hydrogen gases, are detected by using tetraphenylporphyrin (TPP) and quantitated from a calibration curve constructed therefrom, where the range of detectable concentration is made adjustable so that harmful gas can be detected and quantitated over a broad range of concentration. Furthermore, this invention also provides a method for extending the accessible range of gas concentration by adjusting the sensitivity of the detector material via control of tetraphenylporphyrin concentration in matrix polymer of the detector material, by controlling the gas concentration range via measurement at a specific wavelength(s), and by the use of a plurality of detector materials with pre-set assay sensitivity.

Abstract: A computer implemented method for on-line determination of concentrations in an HF alkylation process catalyst stream containing HF acid, ASO, water and optionally an additive which suppresses the vapor pressure of HF acid. The method employs near-infrared spectroscopy coupled with chemometric data analysis. The data analysis uses a partial least squares regression technique which determines unknown concentrations based on spectral calibration data. In use, an absorbance spectrum of material is obtained, e.g., from a slipstream taken from the process alkylation catalyst stream, and the detected spectrum is mathematically analyzed with the aid of the computer to simultaneously predict concentration of HF acid, ASO, water and optionally the additive which suppresses the vapor pressure of HF acid.

Abstract: The present invention discloses a method for improving the speed and sensitivity of optical spectroscopic techniques for remote detection of trace chemical species in a carrier gas. The disclosed method can be applied to any optical spectroscopic detection technique whose sensitivity decreases as the total pressure of the sample decreases. The method employs an inert and non-absorbing buffer gas to supplement the pressure exerted by the carrier gas. This ensures that the total pressure of the sample, and hence sensitivity of the detection technique, remains high. The method is especially useful when measuring concentration of chemical species produced at small rates, and therefore should prove useful for rapid serial screening of combinatorial libraries of compounds.

Abstract: Apparatus and method for determining at least one parameter, e. g., concentration, of at least one analyte, e. g., urea, of a biological sample, e.g, urine. A biological sample particularly suitable for the apparatus and method of this invention is urine. In general, spectroscopic measurements can be used to quantify the concentrations of one or more analytes in a biological sample. In order to obtain concentration values of certain analytes, such as hemoglobin and bilirubin, visible light absorption spectroscopy can be used. In order to obtain concentration values of other analytes, such as urea, creatinine, glucose, ketones, and protein, infrared light absorption spectroscopy can be used. The apparatus and method of this invention utilize one or more mathematical techniques to improve the accuracy of measurement of parameters of analytes in a biological sample.

Abstract: For the purpose of determining the concentration c of an absorbing medium distributed homogeneously in a carrier, even if the film thickness d of the carrier is unknown, an absorbing medium is used whose measured absorption a(.lambda.) deviates from Lambert-Beer's law, in particular in the region of higher concentration, and n.gtoreq.2 model components of the absorbing medium are assumed, so thata(.lambda.)=(.epsilon..sub.1 (.lambda.).c.sub.1 +.epsilon..sub.2 (.lambda.).c.sub.2 + . . . .epsilon..sub.n (.lambda.).c.sub.n).d.The absorption a(.lambda..sub.i) is measured for at least n wavelengths, and the spectral absorption values .epsilon..sub.i (.lambda..sub.i) and concentrations c.sub.i of the model components are computed and the concentration c is determined from the functional relationship between the concentration c and concentrations c.sub.i of the model components c=f(c.sub.i), which relationship is obtained by calibrating measurements.

Abstract: A biosensor based on complexes between biomolecule receptors and colloidal Au nanoparticles, and more specifically, colloid layers of receptor/Au complexes that can be used to detect biomolecule analytes through measuring of binding-induced changes in electrical resistance or surface plasmon resonance. Also disclosed is a method for detecting and analysing carrier-borne chemical compounds with Raman spectroscopy using an improved SERS substrate. Further disclosed is an improved method for detecting compounds in solvents using capillary electrophoresis in conjunction with Raman spectroscopy.

Abstract: Apparatus and method for detecting patient sample quality, and/or analytes, in the tip used to aspirate the patient sample liquid and then dispense it onto a slide test element. Spectrophotometric analysis is done on the liquid while still in the tip, by scanning the tip for transmittance in a light-tight enclosure, using NIR and adjacent visible radiation, and detecting the absorbance spectra of the liquid. Thereafter, or prior thereto, the liquid is dispensed onto a dried slide test element for assaying analytes that are not assayed spectrophotometrically, thus enhancing throughput.

Abstract: A method for determining in vivo the nutritional value of animal feed during the transit of the feed in the digestive system of ruminant comprising analysing said feed, more particularly ensilage, by near infrared spectrophotometry.

Abstract: First and second semiconductor substrate samples formed with a first oxide layer with holes and a third semiconductor substrate sample formed with a second oxide layer having no hole are prepared. The first and the third samples are subject to the same contaminating process for contaminating the surface of the first oxide layer of the first sample and the surface within the hole, and the surface of the second oxide layer of the third sample. All of the first and second layers of the first to third samples are dissolved by the HF vapor. The dissolved solutions are collected and analyzed the amount of contaminating material contained in respective solutions. The contamination amount in the hole is derived from the first, second and third contamination amount from an equation:contamination amount in the hole =first contamination amount-second contamination amount-(surface exposing ratio.times.

Abstract: Early diagnosis of cervical precancer is an important clinical goal. Optical spectroscopy has been suggested as a new technique to overcome limitations of current clinical practice. Herein, NIR Raman spectroscopy is applied to the diagnosis of cervical precancers. Using algorithms based on empirically selected peak intensities, ratios of peak intensities and a combination of Principal Component Analysis (PCA) for data reduction and Fisher Discriminant Analysis (FDA), normal tissues, inflammation and metaplasia were distinguishable from low grade and high grade precancers. The primary contributors to the tissue spectra appear to be collagen, nucleic acids, phospholipids and glucose 1-phosphate. These results suggest that near infrared Raman spectroscopy can be used effectively for cervical precancer diagnosis.

Abstract: This invention teaches a method to identify cellular abnormalities which are associated with disease states. In one aspect, the invention is a method to distinguish premalignant and malignant stages of cervical cancer from normal cervical cells. The method utilizes infrared (IR) spectra of exfoliated cervical cells which are dried on an infrared transparent matrix and scanned at the frequency range from 3000-950 cm.sup.-1. The identification of samples is based on establishing a calibration using a representative set of spectra of normal, dysplastic and malignant specimens. During the calibration process, multivariate techniques such as Principal Component Analysis (PCA) and/or Partial Least Squares (PLS) are used. PCA and PLS reduce the data based on maximum variations between the spectra, and generate clusters in a multidimensional space representing the different populations. The utilization of Mahalinobis distances, or linear regression (e.g.

Abstract: An analytical or preparatory system comprised as a base unit, an adapter, and a substrate. The adapter is attached to an attachment region on the base unit, and the substrate is attached to an attachment region on the adapter. The adapter permits the base unit to be interfaced with a wide variety of different substrates to perform chemical and biological analytical analyses and preparatory procedures.

Abstract: An apparatus for separating a blood component, e.g., fibrin monomer, from blood or plasma ?comprises! includes a container ?(110)! with a reaction chamber for receiving the plasma, where ?said! the reaction chamber is defined by an outer wall and ?comprises! includes means for supplying ?said! the reaction chamber with an agent for converting the fibrinogen content of the plasma into a non-cross-linked fibrin polymer. The apparatus ?comprises furthermore! also includes a device for centrifuging the reaction chamber with the plasma and ?said! the agent to a degree sufficient for separating the non-cross-linked fibrin polymer from the plasma, for depositing ?said! the polymer on the outer wall of the reaction chamber, and for expelling the remaining plasma from the reaction chamber. The container ?(110) comprises! includes means for supplying the reaction chamber with a solvent for dissolving ?said! the non-cross-linked fibrin polymer.

Abstract: The present invention provides a method by which harmful trace gases in a gaseous mixture containing as such harmful halogen gases, halogenated hydrogen gases, acid gases, oxidizing gases, basic gases, organic acid gases, especially halogen gases or halogenated hydrogen gases, are detected by using tetraphenylporphyrin (TPP) and quantitated from a calibration curve constructed therefrom, where the range of detectable concentration is made adjustable so that harmful gas can be detected and quantitated over a broad range of concentration. Furthermore, this invention also provides a method for extending the accessible range of gas concentration by adjusting the sensitivity of the detector material via control of tetraphenylporphyrin concentration in matrix polymer of the detector material, by controlling the gas concentration range via measurement at a specific wavelength(s), and by the use of a plurality of detector materials with pre-set assay sensitivity.

Abstract: A method for assay of an analyte by use of a material labeled with a chemiluminescent substance, which comprises adding a quencher and/or decreasing the specific activity of a chemiluminescent substance labeled probe, thereby decreasing the quantity of chemiluminescence.

Abstract: A method and apparatus for detecting and identifying biological pathogens in a sample includes exposing the sample to an excitation radiation and thereby generating an emission radiation, synchronously scanning the wavelength of the excitation radiation and the wavelength of the emission radiation to produce a spectrum, and correlating the spectrum to a biological pathogen in the sample. In another aspect, a method and apparatus for imaging chemical and biological agents in a sample includes exposing the sample to an excitation radiation and thereby generating an emission radiation and synchronously imaging the wavelength of the excitation radiation and the wavelength of the emission radiation to produce an imaged spectrum.

Abstract: A method of determining or predicting a value P.sub.x of a property of a feed X to a steam cracking process or yield of said process, which method comprises measuring the absorption D.sub.ix of said material at more than one wavelength in the region 600-2600 nm, comparing signals indicative of said adsorptions or a mathematical function thereof with signals indicative of absorptions D.sub.im or mathematical function thereof at the same wavelength for a number of standards S in a bank for which the said property or yield P is known, and choosing from the bank at least one standard S.sub.m with property P.sub.m said standard having the smallest average value of the absolute difference at each wavelength i between the signal for the material and the signal for the standard S.sub.m to obtain P.sub.x, with averaging of said properties or yields P.sub.m when more than one standard S.sub.m is chosen. If desired the method can be used as such to control the steam cracking process by comparison of P.sub.

Abstract: A method of determining the degree of aggregation of the .beta.A4 peptide is disclosed. The method comprises reacting the protein with a suitable binding agent which is capable of binding the .beta.A4 peptide only in its non-aggregated state to form an amount of protein bound binding reagent. The amount of protein bound binding agent is then measured.

Abstract: Systems and methods for material analysis are disclosed in which an organic sample (e.g., a foodstuff, tissue sample or petroleum product) is illuminated at a plurality of discrete wavelengths which are absorbed by fatty acid and fatty acid oxidation products in the sample. Measurements of the intensity of reflected or absorbed light at such wavelengths are taken, and a analysis of absorbance ratios for various wavelengths is performed. Changes in the reflection ratios are correlated with the oxidative state of fatty acids present in the material.

Abstract: A method of monitoring compliance of a patient that has been placed on a medication maintenance program with a prescribed medication dosage by determining a normalized urine methadone concentration. An unadulterated urine sample is obtained from the patient. The urine methadone concentration and urine specific gravity are measured. The normalized urine medication concentration is calculated as a function of the measured medication concentration in the urine and the urine specific gravity. The calculated normalized urine medication concentration is compared with an expected medication concentration value for the patient for the maintenance program prescribed to determine any significant differences therebetween as an indication of noncompliance. Alternatively, a urinary-parameter normalized urine medication concentration is calculated as a function of the measured medication concentration in the urine, the urine specific gravity and at least one selected pharmacokinetic parameter of the medication.

Abstract: The invention relates to a method and apparatus for determining the concentration of at least carbon dioxide in a gas mixture on the basis of the absorption of infrared radiation (2), said apparatus comprising: a radiation source (1), the radiation emitted thereby being aligned to travel through a measuring cell (4) containing a gas mixture (6) to be analyzed; an optical band-pass filter (10), which is transmissive to a first wavelength band and positioned on the path of radiation emerging from the measuring cell or entering into the measuring cell through which the radiation passes; and a first detector (14), positioned in the radiating direction downstream of said first band-pass filter and used for detecting the radiation intensity falling thereon. Said optical band-pass filter (10) has a band-pass which lies within the wavelength range of 4.38 .mu.m-4.47 .mu.m for measuring the total concentration of carbon dioxide by means of the absorption spectrum of a molecule .sup.13 CO.sub.

Abstract: The diffusion through a membrane assaying apparatus and method facilitates rapid detection of small or larger molecular weight substances such as hazardous wastes, toxic chemicals or the like by using a semipermeable membrane having a predetermined molecular weight cutoff. The semipermeable membrane is provided as part of a container having a removable barrier which facilitates control of diffusion through the membrane. The assaying method includes the use of a reaction mechanism for detection of a predetermined substance. The reaction mechanism includes one or more reagents which are designed to either react or compete for a substance for which assaying is being performed. By selecting the proper reagents and molecular weight cutoff of the semipermeable membrane, the presence or absence of a reaction such as a color change or production of vapor provides indication whether the substance being assaying for is present in the test sample.

Abstract: A method of measuring urea nitrogen on the basis of the ultraviolet absorption of urease-GLDH by a reaction rate method, which method not only permits accurate measurement of a sample containing a high concentration of urea nitrogen but also permits accurate measurement of a sample containing polyols such as mannitol without suffering the influence of the polyols, the method comprising hydrolyzing urea in a sample with urease, reacting glutamate dehydrogenase (GLDH) with ammonia formed by the hydrolysis, in the presence of .alpha.-ketoglutaric acid (.alpha.-KG) and reduced-type nicotineamide adenine dinucleotide (NADH) or reduced-type nicotineamide adenine dinucleotide phosphate (NADPH), and measuring the reduced-type nicotineamide adenine dinucleotide (NADH) or reduced-type nicotineamide adenine dinucleotide phosphate (NADPH) for a decrease rate to measure urea nitrogen derived from the urea, and characterized in that a sulfhydryl compound is co-present with the urease.

Abstract: A method and analyzer for monitoring the progress of a chemical process in which a fixed volume sample of the reactive mixture of the chemical process is periodically gathered and injected into a fluid stream of a liquid carrier. The sample in the liquid carrier is passed through an infrared detector which detects the amount present in the sample of a species of the reaction mixture which is indicative of the progress of the chemical process.

Abstract: A method and apparatus for the quantitative analysis of sample liquids. A sample is dried and irradiated with visible and/or infrared light. Light that is diffusely or specularly reflected from the sample and sample carrier is detected. and analysed.

Abstract: An apparatus for on-line measuring physical property data of hydrocarbon products such as octane number, cetane number, density, vapour pressure and the like or gasoline/alcohol ratio, comprising means for providing (N)IR radiation in a predetermined spectral range; means for transmitting light at selected wavelengths in the (N)IR spectral region; means for delivering light from said transmitting means to a hydrocarbon product line; means for allowing an optical path length in the hydrocarbon product line; means for detecting the light transmitted through the said optical path; means for providing the obtained signal to be input to processing equipment for spectral analysis and correlating the spectral data to the physical property data of hydrocarbon products such as octane number, cetane number, density, vapour pressure and the like or gasoline/alcohol ratio.

Abstract: Apparatus and method for detecting patient sample quality, and/or analytes, in the tip used to aspirate the patient sample liquid and then dispense it onto a slide test element. Spectrophotometric analysis is done on the liquid while still in the tip, by scanning the tip for transmittance in a light-tight enclosure, using NIR and adjacent visible radiation, and detecting the absorbence spectra of the liquid. Much smaller liquid volumes, and no through-the-label detection, are required, compared to doing the scanning of the liquid in a primary patient collection container.

Abstract: This invention relates to a lytic reagent and a method of using the lytic reagent for automatically determining leukocyte subpopulations in blood. More specifically, the new lytic reagent lyses red blood cells and affects the eosinophils which enables the differentiation of at least one subpopulation of leukocytes. The lytic reagent is an acidic, hypertonic aqueous solution containing alkali metal salt of alkyl sulfite, an eosinolytic agent, a nonionic surfactant and a physiological salt. When used in combination with a second lytic reagent system, one is able to obtain at least a five part differential of leukocytes using DC and RF measurements.

Abstract: A liquid and gas analyzing system that provides a sample collecting probe that delivers the sample through inert materials to prevent any contamination. For gas analyzing for environmental monitoring process control, a sample collecting probe having a borosilicate glass tube liner connected through an inner spiral tube to the analyzer prevents contamination. The system then delivers the sample to a single pass radiated optical cell by a light beam. The light beam is collected by a miniature CCD array spectrometer and delivered to an industrial PC. The output from the industrial PC is then delivered to a software controlled data acquisition system for analysis. The system is constructed to be a modular in design allowing addition of complementary components for measuring and analyzing different materials.

Abstract: Fractional-volatilization separation systems and methods are disclosed which enable a stable, continuous, non-bubbling liquid flow, essentially constant surface area/volume ratio, temperature controlled, fractional volatilization of volatile/semi-volatile components in a liquid analyte or component containing sample. The fractional volatilization separator system can be utilized in small scale analytical and large scale chemical purification, concentration and desalinization applications. Continuous rapid removal of residual liquid sample can provide concentrated non-volatile component/analyte solution, and allows quick and easy washout between sequential use with different liquid samples.

Abstract: A method of flow cytometric analysis of leukocyte subpopulations using a fluorescence trigger and gating on light scatter vs. fluorescence. The methods are useful where light scatter parameters are unsatisfactory for identification of leukocyte subpopulations, for example when analyzing lysed blood samples without removal of lysing reagent or unbound label prior to analysis.

Abstract: A plurality of light emission molecules, having different light emission lifetimes, are irradiated with excitation light so that the light emission molecules emit light. The emitted light is divided into at least two different wavelength regions. Temporal changes in each of the at least two wavelength regions of the light emission is measured over at least two different time periods. Information on energy transfer generated between the plurality of light emission molecules is determined based on the measured results in each of the wavelength regions over each of the time periods.

Abstract: The invention relates to methods for simultaneously or sequentially detecting multiple nucleic acid analytes in a single medium utilizing oligonucleotide hybridization probes coupled to different chemiluminescent labeling reagents. The methods may be used in a heterogeneous, homogeneous or non-homogeneous assay system. The invention also relates to specific combinations of chemiluminescent labeling reagents suitable, when coupled to an oligonucleotide probe, for use together in methods for the detection of multiple nucleic acid analytes. The invention also concerns kits useful in these methods.

Abstract: A flame based method for analyzing a sample by introducing the sample into a combustible gas mixture, igniting the combustible gas mixture to produce a flame, and detecting a characteristic of the resulting flame to determine the identity and/or concentration of one or more chemical substances in the sample, wherein the combustible gas mixture is generated by water electrolysis. The same method is also utilizable for determining the identity and/or concentration of one or more chemical compounds in the sample. A flame based detector apparatus for analyzing a sample is also described.

Abstract: The invention relates to a reaction chamber, which includes a cylindrical vessel, with at one end, at least one inlet or outlet tube or lead-through fitted with a valve for a liquid or gaseous component. The other end of the vessel is open. The reaction chamber further comprises a plunger, which performs a reciprocating movement within the cylindrical vessel in axial direction through the open end of the vessel. The plunger tightens against the inner wall of the cylindrical vessel, and has at least one channel, in substantially axial direction, fitted with a valve or connected to a tube fitted with a valve. The invention relates also to an assay method based on the use of the reaction chamber.

Abstract: A gas analyzer system for providing a spectroscopic analysis of the sample gas. This analysis is accomplished by first introducing the sample gas into the inlet of the system and transporting it to a spectral analyzer. The sample gas is then spectrally analyzed and the analyzer outputs a signal indicative of a radiation intensity spectrum associated with the analyzed sample gas. A processing unit uses the analyzer signal to detect the presence of one or more prescribed gases and to determine the concentration of each of the prescribed gases in the sample gas. Next, the reacting agent is supplied to the sample gas to convert one or more gases whose presence in the sample gas cannot be detected via spectral analysis due to the masking effects other gases present in the sample gas. The masked gases are converted to secondary gases at least one of which is readily detectable via spectral analysis.