Abstract: The invention concerns test elements and methods for the optical detection of an analyte in a sample. The test element includes a support having at least one transparent portion, and a one-layer film positioned on the support. The film has a thickness when dry of less than about 10 ?m. The method includes contacting the sample with the test element and determining the analyte concentration in the sample.

Abstract: An object is to provide a reaction detecting device in which a height dimension of the device itself can be set to be small to realize space saving, unevenness of measurement sensitivity for each reaction container is minimized, and high-sensitivity and high-precision reaction detecting is possible, the device includes: a reflective plate disposed above a temperature controllable reaction block disposed in a reaction chamber constituted in a main body to reflect light; and a light source lamp and a camera arranged in the main body, the light from the light source lamp is reflected by the reflective plate to enter each reaction container from above, and light such as fluorescence directed upwards from a reaction specimen is reflected by the reflective plate to enter the camera.

Abstract: A method of separating a cell-containing sample into a substantially cell-depleted portion, and a cell-containing portion comprising at least one of a stem cell, a lymphocyte, and a leukocyte comprises a step in which the sample is received in a vessel with at least one flexible wall. In another step, an additive and particles are added to the sample, wherein the additive substantially binds to the at least one of the stem cell, lymphocyte, and leukocyte, and the particles and wherein the particles substantially bind to the at least one of the stem cell, lymphocyte, and leukocyte, and the additive, thereby producing a cell-containing network. In a further step, the network is separated from the substantially cell-depleted portion by applying a magnetic force.

Abstract: The present invention provides an apparatus for the chemical analysis of a sample.

Abstract: Analyzers and methods of analysis are described for performing blood cell counting and immunoassay on a whole blood specimen in one measurement section. An assay sample is prepared by blending carrier particles sensitized with an antibody or an antigen against a substance to be immunoassayed and a fluorescent dye for staining blood cells with the whole blood specimen. Optical information is detected from a particle in the assay sample, and the blood cells are differentiated and counted based on the detected optical information. A rate of agglutination of the carrier particles is obtained based on the detected optical information, thereby enabling detection of the substance to be immunoassayed.

Abstract: A method and apparatus automates and accelerates the extraction and analysis of trace elements from biomass. The method and apparatus are especially useful at key segregation points in the food chain where speed and accuracy is necessary to separate agricultural cereals that are elevated in beneficial trace element content which provides higher value to the producer.

Abstract: An optical reader system is described herein that uses a scanned optical beam to interrogate a biosensor to determine if a biomolecular binding event occurred on a surface of the biosensor. In one embodiment, the optical reader system includes a light source, a detector and a processor (e.g., computer, DSP). The light source outputs an optical beam which is scanned across a moving biosensor and while this is happening the detector collects the optical beam which is reflected from the biosensor. The computer processes the collected optical beam and records the resulting raw spectral or angle data which is a function of a position (and possibly time) on the biosensor. The processor can then analyze the raw data to create a spatial map of resonant wavelength (peak position) or resonant angle which indicates whether or not a biomolecular binding event occurred on the biosensor. Several other uses of the raw data are also described herein.

Abstract: A variety of types of molecules are detected and/or analyzed using an integrated micro-circuit arrangement. According to an example embodiment of the present invention, a micro-circuit arrangement detects excitable target markers in response to an excitation source. The excitation source emits a first electromagnetic radiation to excite one or more target markers into emitting a second electromagnetic radiation. The excitation source and detector combination can be optimized to detect a specific characteristic of a biological specimen. In this manner, an excitation source can be combined with several optical-detectors or detection channels, where each optical-detector is measuring or sensing the same or different characteristic of the biological specimen.

Abstract: A variety of characteristics of body fluid may be measured by introducing a sample to a textured surface on optical material such as waveguides and sheets. The textured surface presents a field of elongated projections which are spaced apart to exclude certain components of the body fluid sample from entering into the spaces between the projections, while permitting other parts of the body fluid sample which contains the analyte to enter into those spaces. The analyte contacts a chemistry on the surface which is sensitive to the analyte, whereupon the analyte and the analyte-sensitive chemistry interact in a manner that is optically detectable. The optical material is packaged in suitable structures such as elongated cylinders, flat test strips, and sheets. A structure containing the optical material is mounted on a detector, which both illuminates the optical material and detects and analyzes the light that returns from the textured surface.

Abstract: This invention provides protein or polypeptide imprinted polymers with integrated emission sites (PIPIES) for detecting the presence of a protein or polypeptide analyte comprising templated sites which are specific for the analyte. At or near the templated sites are selectively placed reporter molecules. A method is also disclosed for the preparation of the PIPIES and the use of these for the detection of analytes.

Abstract: Apparatus and methods for screening a library of materials. Materials are provided in a plurality of locations on a substrate. The locations include first regions that are sufficiently transparent to a first form of radiation to permit analysis of the portion of the sample material supported in the first region using a first analytical technique, and second regions that are sufficiently transparent to a second form of radiation to permit analysis of a portion of the sample supported in the second region using a second analytical technique, but are insufficiently transparent to the first form of radiation to permit analysis of the portion of the sample material supported in the second region using the first analytical technique. Sample materials are screened at one or more sample locations of the substrate using the first analytical technique in the first region and the second analytical technique in the second region.

Abstract: There is disclosed an apparatus and method for detecting and measuring volatile acidic or basic components including ammonia, ammonium, or volatile amines (compound) in a gas or liquid state fluid. Specifically, the present invention provides a PTFE-carrier solid phase indicator film having an ammonia-sensitive indicator dye embedded therein, such that the dye moiety changes color or spectral properties upon exposure to the compound to be detected.

Abstract: A fecal analyzing apparatus includes an extraction/dilution section (43) for extracting a fecal suspension from a feces sampling container (1). The fecal suspension is formed by dispersing feces in a feces-dissolving liquid in the feces sampling container (1), and mixing a diluting solution having a different concentration than the feces-dissolving liquid, with respect to a specific pigment, into the extracted fecal suspension in a predetermined amount. An optical-absorbance measurement section (61) detects the concentration of the specific pigment to be changed in response to the addition of the diluting solution, and a control device (66) determines the adequacy of the extraction amount of the fecal suspension in accordance with the detected concentration of the specific pigment. The adequacy of the extraction amount of the fecal suspension can be determined to provide an adequate assay result.

Abstract: A nanostructure is used to generate a highly localized nanoscale optical field. The field is excited using surface plasmon amplification by stimulated emission of radiation (SPASER). The SPASER radiation consists of surface plasmons that undergo stimulated emission, but in contrast to photons can be localized within a nanoscale region. A SPASER can incorporate an active medium formed by two-level emitters, excited by an energy source, such as an optical, electrical, or chemical energy source. The active medium may be quantum dots, which transfer excitation energy by radiationless transitions to a resonant nanosystem that can play the same role as a laser cavity in a conventional laser. The transitions are stimulated by the surface plasmons in the nanostructure, causing the buildup of a macroscopic number of surface plasmons in a single mode.

Abstract: The methods and apparatus disclosed herein concern nanoparticle layers uniformly distributed on a surface or substrate. In certain embodiments of the invention, the nanoparticle layers are of use for Raman spectroscopy. In certain embodiments of the invention, a micelle-metal ion complex is formed and deposited on a surface. The polymer component of the micelle-metal ion complex may be removed resulting in formation of nanoparticles of a uniform size and distribution. The polymers may contain one or more ligands. The number and type of ligands in a micelle will determine the type and amount of metal ion bound to the micelle, in turn determining the metal composition and size of the nanoparticles. The distribution micelle-metal ion complexes on a surface may determine the distribution and periodicity of the nanoparticle layer. In other embodiments, rod or columnar-shaped nanoparticles may be generated. Other embodiments concern the generation of uniform alloy nanoparticles.

Abstract: A liquid analyser has a reactor portion and an associated measurement portion. A sample pump is operable to deliver a liquid sample to a reactor vessel. A base pump supplys a base solution to the reactor vessel. An ozone generator supplies ozone to the reactor vessel. The liquid sample is oxidised in the reactor vessel by means of hydroxyl radicals which are generated using the base solution and ozone to reduce complex components of the liquid sample to their lowest state in solution. The oxidised sample solution is delivered to an optical detector in the measurement portion to determine the concentration of one or more selected materials such as nitrogen, phosphorous or a heavy metal in the oxidised sample solution.

Abstract: A method of making an optochemical sensor, the method comprising: providing a reflective substrate having a major surface; affixing a detection layer comprising at least one intrinsically microporous polymer to at least a portion of the major surface; depositing a substantially continuous semi-reflective metallic layer on at least a portion of the detection layer, the semi-reflective metallic layer comprising palladium and having a network of fine irregular cracks therein; and heating the detection layer and semi-reflective metallic layer in the presence of molecular oxygen at a temperature sufficient to cause the cracks to widen. Sensors prepared according to method are also disclosed.

Abstract: An analyzer for oxidizing and measuring samples containing some liquid comprising: a reactor vessel; a sample pump; a base pump connected to a base reservoir; an ozone generator adapted to create and flow ozone; an acid pump connected to an acid reservoir; a sampling valve connected to the sample pump, the acid pump, and the base pump; a circulation pump connected to the reactor vessel for mixing the sample, the liquid acid, the liquid base, and the ozone to oxidize at least a portion of the sample to its lowest state forming an oxidized liquid sample; a sample chamber for receiving the oxidized liquid sample; an analysis pump in communication with the sample chamber; and a measuring cell for receiving the oxidized liquid sample, measuring the oxidized liquid sample with a detector to optically measure at least one frequency of absorption of at least one component in the sample.

Abstract: A substance identification system is configured to identify at least one detection target faster and with greater accuracy than is possible using prior substance identification systems and/or prior substance identification techniques. A chamber includes a pellet forming area having a predetermined geometry that is configured to maximize a ratio of a pellet surface area to a pellet volume. A magnet is positioned on one side of the chamber and configured to form a pellet of aggregated magnetic particles in the pellet forming area. A laser source is positioned on the same side of the chamber as the magnet and configured to illuminate the pellet, when the pellet is formed in the pellet forming area.

Abstract: A system and method for determining the concentration of an analyte in a fluid sample includes a test strip having a first and second portion separated by a bend line formed in the base. The bend line traverses the longitudinal axis of the base and the base is adapted to bend about the bend line. The test strip further includes a test element disposed on one of the portions. The test strip includes a reagent adapted to react with the analyte in the fluid sample.

Abstract: A flow cell and flow cytometer in which a nozzle at the end of a flow channel is disposed on a removable substrate held at a registered location on a flow cell. Other elements including illumination optics, light collection optics, and the flow cell may then be positioned at fixed locations and would not require subsequent periodic adjustment. The registered location for positioning the nozzle allows removal and replacement of the nozzle key with the nozzle subsequently positioned in the identical location.

Abstract: The invention discloses a detection method using nanoaggregate-embedded beads and system thereof, which are characterized in that the nanoaggregate of Raman dye and metal nanoparticles is coated by an inorganic oxide to form a nanoaggregate-embedded bead, and which is then conjugated with a probe molecule to form a sensor bead. The Raman spectra of the product formed by binding of the sensor bead and an analyte in a sample is detected for determining whether the analyte exists in the sample. In embodiment, the pH of the solution of metal nanoparticles is controlled to keep at 10, and the concentration of the Raman dye is controlled to keep between 1×10?6M and 2×10?6M for reducing the size of the nanoaggregate.

Abstract: A highly sensitive fluid composition analyzer where a fluid may be placed in contact with a very small area on a material sensitized to change color in the presence of a specific type of compound, to be impinged with light. The light reflected, transmitted and/or scattered by the material may serve as input for the analyzer electronics. The fluid may be pre-concentrated prior to being brought in contact with the material. The area on the material may be a spot having an outside dimension of less than one millimeter.

Abstract: Techniques for integrating optoelectronic system and microfluidic system. An apparatus for optical analysis includes a detector system and a microfluidic system on the detector system. The apparatus is free from any lens system between the microfluidic system and the detector system. Methods of making such an apparatus and using such an apparatus are also disclosed.

Abstract: Various embodiments disclose a colorimetric absorbance measurement method and a system for performing the same. The method comprises driving a reaction tray carrying a plurality of reaction cuvettes to rotate at a speed; transferring or rotating filters on a filter wheel to a light path of a light beam, starting from a filter of a first wavelength; and sampling photoelectric data when the light beam has passed through each reaction cuvette in some embodiments. The method ensures consistency in the measurement and synchronization between the calibration and the sample test and reliability of the measurements. Various embodiments simplify data processing and reduce the complexity of the system.

Abstract: A microchip includes fluid circuits therein, formed by uniting together at least a first substrate that is a transparent substrate and a second substrate having grooves provided at the substrate surface and/or through holes penetrating in a thickness direction. The fluid circuits include a liquid reagent receptacle unit to store a liquid reagent, a quantification unit to quantify the liquid reagent or specimen, and an overflow liquid storage unit connected to the quantification unit to store the liquid reagent or specimen overflowing from the quantification unit during quantification. There is also provided a method of using the microchip.

Abstract: A device for detecting the presence of an antigen including (1) a cell having antibodies which are expressed on the surface of the cell and are specific for the antigen to be detected, where binding of the antigen to the antibodies results in an increase in calcium concentration in the cytosol of the cell, the cell further having a emitter molecule which, in response to the increased calcium concentration in the cytosol, emits a photon; (2) a liquid medium for receiving the antigen and in which the cell is immersed; and (3) an optical detector arranged for receiving the photon emitted from the cell.

Abstract: A sensor that includes an assembly having a flexible base material and a flexible material layer formed on the flexible base material. Both the flexible base material and the flexible material layer have shrinkable and/or stretchable properties. The flexible base material may include a shrinkable polymer (e.g. PVC/PET or “shrink wrap”), which may shrink up to 500%. The flexible base material may include a stretchable polymer (e.g. Mylar), which may be stretched by at least 1000%. These stretchable and shrinkable properties may be exhibited without substantial functional degradation of either the flexible base material and/or the flexible material layer.

Abstract: The microfluidic reverse affinity-blot device of the present disclosure combines affinity binding for isolation and/or enrichment of protein(s) from a sample, followed by separation/identification thereof. In general terms, a microfluidic reverse affinity-blot device is a closed system of interconnected components that is comprised of defined points of entry and exit, wherein the interconnected components include a capture region upstream from a protein separation region and subsequent detection region. Methods of use are also described.

Abstract: An assay device for testing of liquid samples for drugs of abuse has a transparent container for retaining a liquid sample. A backing member is within the container and is curved so that its front surface corresponds to the curvature of the container wall. Immunoassay test strips are on the front face of the backing and are visible through the container wall. Each test strip is enclosed in a transparent pocket which has a bottom opening through which the bottom portion of the test strip protrudes to contact the liquid sample within the container. The liquid then flows upwardly through the test strip to react with reagents within the test strip.

Abstract: Array scanning methods that focus on the far side and devices configured for use in the same are provided. In reading arrays according to the subject methods, an array is placed in a reading position of a scanning device so that the nominal focal plane of the scanning device is present within the array substrate at a predetermined fixed substrate thickness fraction distance from the far-side of the array, and the array is then read by the device. As such, the subject scanner devices of the present invention are configured to hold an array substrate in a reading position of the device in which the device's nominal focal plane is present within the array substrate. The subject methods and devices find use in a variety of different applications, including both genomic and proteomic applications.

Abstract: The present invention generally relates to the determination of an analyte concentration (quantitative determination) or whether an analyte threshold level has been passed (qualitative determination) in a biological sample through employment of a disposable analytical microprocessor device. The device can include a batch-specific, self-executable algorithm for the calculation of the analyte concentration.

Abstract: A direct rapid automated protein analyzer is disclosed. The protein analyzer includes means for reducing protein samples to small particles, a reaction vessel in material transfer communication with the homogenizer, a reservoir for binding dye composition in fluid communication with the reaction vessel, a metering pump in fluid communication with the reservoir and the reaction vessel for distributing discrete predetermined amounts of a binding dye composition to the reaction vessel, a filter in fluid communication with the reaction vessel for separating solids from filtrate after a dye binding reaction has taken place in the reaction vessel, and a calorimeter in fluid communication with the filter and the reaction vessel for measuring the absorbance of the filtrate from the reaction vessel and the filter. The rapid analyzer can be used in conjunction with a kit that includes a sample cup for mixing a protein sample with a dye-binding solution and a filter holder for being positioned in the sample cup.

Abstract: Water soluble analytical agents for chlorine analysis of water are delivered into a sample from a support that is beneficially moved in the sample to assist delivery and mixing. Beneficially, an immediate photometric analysis of free chlorine is provided, and variability of measurements is reduced. Advantageously, the analysis is a touch-free chlorine analysis.

Abstract: The invention relates to a process for producing a flow cell for the spectroscopic analysis of samples to be passed through, the process comprising the following steps: (a) provision of a first (10) and of a second (22) window, the second window (22) having at least two sample flow channels (24) for supplying and removing the sample to be analyzed; (b) application of a structured thin layer (18) to one of the windows (10, 22); (c) contacting and liquid-tight securing of the thin layer (18) to the other (22, 10) window, in such a way that facing, plane-parallel window surfaces (14, 20) of the windows (10, 22) and the thin layer (18) delimit a flow chamber (26) which is accessible only through the sample flow channels (24), the windows (10, 22) being optically transparent at least in some regions at least in the region of the flow chamber (26); and (d) filling at least some regions of a filling chamber (28) between the windows (10, 22) which is separated from the flow chamber (26) by the thin layer (18) and ad

Abstract: Disclosed herein is an automatic analyzer which determines a vessel blank value of the automatic analyzer based on a criterion associated with the sensitivity of an analysis item to determine whether or not a vessel is usable. An automatic analyzer includes: an operation unit for calculating an absolute value of a difference between a vessel blank value immediately before measurement of the analysis item and a vessel blank value under periodical measurement to determine whether or not a vessel is usable for measurement based on a plurality of criteria set for each analysis item; and a function of issuing an alarm if the vessel blank value is not judged to be within a criterion.

Abstract: It is intended to provide a method for determining homogenization and/or reaction completion, capable of making the measurement time necessary and sufficient and enhancing the measurement speed, and a method for measuring solution concentration using the same. According to the method for determining homogenization and/or reaction completion and the method for measuring solution concentration using the same, homogenization and reaction completion are determined based on the optical property of the liquid mixture of a test liquid and a reagent liquid.

Abstract: A use composition monitor determines the concentration of peracid and/or peroxide in a use composition using a kinetic assay procedure. A sample mixture containing a sample of the use composition, a diluent and at least one reagent is prepared and analyzed using, for example, an optical detector. Response data obtained by the detector is indicative of the optical absorbance of the sample mixture as a function of time. A processor analyzes the response data to determine a corresponding best fit linear relationship. The initial absorbance of the sample mixture is indicative of the concentration of peracid in the use composition, while the slope of the best fit equation is indicative of the concentration of peroxide in the use composition.

Abstract: Portable devices and methods for determining the presence of a target analyte using a portable device are provided. The portable device is preferably hand-held. A sample is injected to the portable device. A microfluidic separation is performed within the portable device and at least one separated component detected by a detection module within the portable device, in embodiments of the invention. A target analyte is identified, based on the separated component, and the presence of the target analyte is indicated on an output interface of the portable device, in accordance with embodiments of the invention.

Abstract: A lytic reagent composition and methods for differential analysis of leukocytes are disclosed. In embodiments, the analysis may utilize optical measurements in flow cytometry based hematology analyzers. The reagent system includes an anionic surfactant in a hypotonic solution, an inorganic buffer to maintain the pH in a range from about 6 to about 10, and optionally a leukocyte stabilizer. The reagent system is used to lyse red blood cells and stabilize the leukocytes to enable multi-part differentiation of leukocytes in a near physiologic pH environment on a flow cytometry based hematology analyzer using axial light loss, light scatter intensity, high-numerical aperture side scatter, and time-of-flight measurements.

Abstract: An analyzer for measuring an FRET (fluorescence resonance energy transfer) efficiency of a specimen containing a donor and an acceptor. The analyzer has an illuminator, an optical system, a detector and a calculator. The illuminator emits light for donor excitation and acceptor bleaching. The detector detects fluorescence from the specimen. The calculator calculates the FRET efficiency using the output of the detector. The detector independently detects the fluorescence in wavelength regions. One of the regions has a larger overlap with the fluorescence spectrum of the acceptor than with that of the donor.

Abstract: A method and apparatus for measuring Tot-Hb in a sample are provided. The method involves collecting absorbance measurements of a sample using a spectroscopic apparatus that includes a first primary calibration algorithm for one of Oxy-Hb, “Oxy-Hb plus Deoxy-Hb”, or “Total-Hb minus Met-Hb” and a second primary calibration algorithm for one or more than one of Met-Hb, Carboxy-Hb, or Sulf-Hb, or includes a third primary calibration algorithm obtained by adding terms of the first primary calibration algorithm and the second primary calibration algorithm together. Followed by predicting either a first value for one of Oxy-Hb, “Oxy-Hb plus Deoxy-Hb,” or “Total-Hb minus Met-Hb” and predicting second value for one or more than one of Met-Hb, Carboxy-Hb, or Sulf-Hb in the sample and adding the first and second value together, or predicting a value for Total-Hb.

Abstract: A test apparatus is for testing a DNA substrate on which a plurality of DNA fragments for testing are arranged, wherein absolute precision is not required. A substrate is provided on which a plurality of biomolecule spots containing a group of biomolecules (e.g., DNA, etc.) of a specific type are formed, where the pattern or position of the DNA spot is changed depending on specific data so that information of the specific data is recorded on the substrate.

Abstract: An apparatus for measuring a glucose concentration is noninvasive, accurate, and compact. The apparatus includes a detection unit (10) and a principal component analysis (PCA) unit (20). The detection unit includes a light source (11) to emit mid-infrared light, an ATR prism (12) to receive the mid-infrared light with a measuring object placed on the ATR prism, and a spectrum detector (13) to detect an absorption spectrum from the mid-infrared light from the ATR prism. The PCA unit includes a loading memory (24) to store a glucose corresponding loading and a personal data memory (28) to store personal data in the form of a calibration curve. According to the detected absorption spectrum, stored loading, and stored personal data, the PCA unit computes a glucose concentration of the measuring object.

Abstract: Electrochemical devices, methods, and systems for detecting and quantifying analytes are disclosed. A chemical detection reagent is locally generated in a test solution by electrochemical reaction of a precursor compound caused to migrate into the test solution from a precursor solution separated from the test solution by a cell separator. This approach provides precise metering of the reagent, via the charge passed, and avoids the need to store a reagent solution that may be chemically unstable. In one embodiment, the starch concentration in a colloidal solution can be measured via spectroscopic detection of a blue complex formed by the interaction of starch with iodine produced, on demand, by electrochemical oxidation of iodide ion. The approach may also be used to characterize certain types of analytes. The invention is amenable to automation and is particularly useful for on-line monitoring of production processes, including the inclusion of feed back loop mechanisms for process control.

Abstract: A method of tracing an aqueous liquid, particularly an aqueous urea used for addition to a selective catalytic reduction system to remove NOx from diesel exhaust includes adding a tracer comprising a pre-determined amount of a phenol to the liquid. The liquid can subsequently be identified by reacting a sample with a reagent containing a predetermined amount of 4-aminoantipyrine in the presence of an initiating compound such that the reaction between the reagent and a phenol in the liquid produces a chromophore and measuring the absorbance of the resulting solution of the chromophore.

Abstract: A system and method employing infrared laser spectrography and dual wavelength modulation to monitor the concentration of a gas, such as oxygen or carbon dioxide, in the sample vial, or to monitor the pressure in the sample vial, to thus detect for microorganism growth in the sample vial. The system and method each employ an energy emitting device, such as an infrared laser, a detector and a signal analyzer, such as a spectroscopy device. The infrared laser emits toward the container infrared energy having a substantially single wavelength substantially equal to a wavelength at which the gas absorbs the infrared energy. The detector detects a portion of the energy signal that passes through the container, and the signal analyzer spectroscopically analyzes the detected portion of the energy signal to determine whether the gas exists in the container, or to determine the pressure in the container.

Abstract: A structure having an opening communicating with an inner space is adapted for separating or capturing a substance introduced from the opening into the inner space. The structure comprises a hollow member having the inner space with the opening and plural pillars positioned mutually separately in the inner space. The pillars are formed of a material containing an inorganic oxide and different in composition from the hollow member.

Abstract: A Fabry-Perot cavity has a pair of partially transmissive, partially reflective, surfaces. A first of the surfaces is flexibly suspended adjacent and parallel to a second of the surfaces. A gap exists between the surfaces. A variable electrostatic potential permits this gap to be adjusted. A translucent chemical layer is disposed on the first surface. A photosensor is attached to the second surface. Light irradiates the photosensor through the chemical layer and the first and second surfaces wherein the light is also partially reflected between the surfaces. A sensing environment is provided wherein an agent undergoes a reaction with the chemical layer as well as an environment wherein the reaction does not occur. The output of the photosensor is measured to assess a change in spectrum and spectral intensity for each of the sensing environments. The gap between the surfaces as well as the light used are selected to provide an optimum photosensor output.

Abstract: A detector for detecting vapors emitted from analytes includes a housing, a pump and a sensing assembly. The housing has an inlet, an outlet and an enclosed sensing volume therebetween. The pump communicates with the housing for moving a carrier sequentially through the enclosed sensing volume at a predetermined flow rate. The sensing assembly senses the vapors of the analyte delivered by the carrier as the carrier passes through the housing. The sensing assembly includes a sensing unit constructed of an amplifying fluorescent polymer, a source of excitation, a detector, and a convertor assembly.