Abstract: A method of determining an amount of at least one molecular species in a sample from an image of the sample captured by an image acquisition device is provided, each molecular species being indicated by a dye. A dye space representation of a plurality of dyes is formed by orthogonally adding the correspondence tables of the dyes, each correspondence table having a plurality of normalized RGB triplets and incrementally extending from 0% to 100% transmittance. The dye space representation has one dimension for each dye and provides a reference model for a combination of the plurality of dyes. Each pixel of an image of the sample stained with the combination of the plurality of dyes is compared to the reference model, each pixel having a color defined by an RGB triplet, so as to determine an optimal combination of normalized RGB triplets from the respective correspondence tables of the dyes producing the color of the respective pixel.

Abstract: Detection and characterization of immunologically detected substances are performed electronically on human and animal biological fluids such as whole blood, serum, plasma, urine, milk, pleural and peritoneal fluids, and semen, which fluids are contained in a thin chamber forming a quiescent fluid sample, which chamber has at least two parallel planar walls, at least one of which is transparent.

Abstract: A method determines an analyte concentration in a sample. The sample includes the analyte and a substance. The method includes providing absorption data of the sample. The method further includes providing reference absorption data of the substance. The method further includes calculating a substance contribution of the absorption data. The method further includes subtracting the substance contribution from the absorption data, thereby providing corrected absorption data substantially free of a contribution from the substance.

Abstract: A flow cytometer capable of using electronics to analyze a large dynamic range while avoiding and/or correcting traditional limitations of acquisition electronics. The invention allows for measuring signal characteristics, which may include but are not limited to linear peak, integral, logarithmic peak, and pulse width. Other system parameters may also be generated by the invention to indicate timing or status information. Accurate and precise measurements may be performed by correcting for input errors if needed, and by transforming the input signal to produce a more easily measured form.

Abstract: Methods for determining the responsiveness of a patient to recombinant human erythropoietin therapy are disclosed. In one approach, the method includes obtaining a volume-Hgb factor (VHf) defined as a product function of MCV and Hgb from a patient's blood sample; comparing VHf to a predetermined criterion; and reporting indication of responder if VHf meets the predetermined criterion. The method further includes using a RBC size-hemoglobin factor (RSHf) defined as a product function of MCV, MRV and Hgb, or using a function of VHf and RDW for determining the responsiveness. In another approach, the method includes using a RBC size factor (RSf) defined as a product function of MCV and MRV, in combination with transferrin saturation (TSAT) for determining the responsiveness to the erythropoietin therapy.

Abstract: Various optical apparatus, in particular embodiments, may provide a source of parallel light (7, 75). The parallel light (7, 75) may be generally achieved by directing an incident beam at the apex of a prism (1, 22, 24, 26, 28). The prism may have varying configurations. One configuration has a forward conical face (24). Another configuration has a pyramidal forward end (22). Other configurations are also disclosed. Various optical methods and methods for flow cytometry are also disclosed.

Abstract: A component measuring device for measuring the quantity and/or the property of a given component in a specimen by calorimetrically measuring a test strip includes a tip mount on which is to be mounted a tip having the test strip, and a photometric unit. The photometric unit comprises a light-emitting element that applies light to the test strip while the tip is mounted on the tip mount, a light-detecting element that detects light reflected from the test strip, and a holder in which is held the light-emitting element and the light-detecting element. The holder possesses a passage through which passes the light and the reflected light. A light-transmissive member closes the passage with a sealing member interposed therebetween in a portion of the holder which faces the test strip. The component measuring device can also be provided with a stain detecting device which is adapted to detect a stain on the light-transmissive member.

Abstract: A device for determination of analytes is disclosed that comprises an optical material having a deposit on a surface thereof, where this deposit includes an analyte-reactive reagent and a particulate means for enhancing reflectance of a light beam emitted through the optical material into the analyte-reactive reagent. The enhanced reflectance provides a return of light through the optical material at a level which is not only analytically useful, but involves sufficient returned light intensity so as to enable markedly improved accuracy in analytical determinations. The particulate means most preferably includes hollow spherical particles.

Abstract: A nonhemolytic sensor for determination of analytes in erythrocyte-containing biological fluids is disclosed that comprises an optical material having a deposit on a surface thereof, where this deposit includes an analyte-reactive reagent and a particulate means for suppressing hemolysis of erythrocytes in an erythrocyte-containing biological fluid, such as whole blood. Thus, a porous array of negatively charged particles, e.g., polymeric beads having a plurality of carboxylate surface groups, are disposed on a sampling surface of an optical sensor, and suppress hemolysis of erythrocytes coming into contact with the sampling surface. In the case of an optical sensor, such particles can simultaneously enhance reflectance of a light beam transmitted through the optical material to the sampling surface site.

Abstract: A reagentless whole-blood analyte detection system that is capable of being deployed near a patient has a source capable of emitting a beam of radiation that includes a spectral band. The whole-blood system also has a detector in an optical path of the beam. The whole-blood system also has a housing that is configured to house the source and the detector. The whole-blood system also has a sample element that is situated in the optical path of the beam. The sample element has a sample cell and a sample cell wall that does not eliminate transmittance of the beam of radiation in the spectral band.

Abstract: A sample analyzer is provided that is capable of eliciting sufficient performance of an avalanche photodiode, and performing high-precision analysis of the sample. The sample analyzer is provided with a WBC detection section that uses the avalanche photodiode as a photoreceptor element. The WBC detection section is provided with a flow cell, semiconductor light source, side collective lens, dichroic mirror, and avalanche photodiode. The side collective lens is a lens with a high NA (numeric aperture), and an aspheric lens with a small aberration. The sample analyzer prepares a scattergram using side fluorescent light signals and side scattered light signals to classify white blood cells into five categories.

Abstract: A method determines the concentration of a substance in a subject's blood. The method includes measuring an interaction of at least one light beam with a portion of the subject's body. The method further includes calculating a value of an optically-measured parameter indicative of the interaction of the at least one light beam with the substance in the portion of the subject's body. The method further includes measuring values of one or more temperature-indicative parameters corresponding to a temperature of the portion of the subject's body. The method further includes accessing an empirical correlation of the optically-measured parameter and the one or more temperature-indicative parameters to concentrations of the substance in blood. The method further includes obtaining a concentration of the substance in the subject's blood using the empirical correlation. The concentration corresponds to the value of the optically-measured parameter and the values of the one or more temperature-indicative parameters.

Abstract: A method determines the concentration of a substance in a subject's blood. The method includes noninvasively irradiating an eye with a measurement light beam having a first wavelength and a first power and with a reference light beam having a second wavelength and a second power. The second wavelength is different from the first wavelength. The method further includes measuring at least one of a body temperature of the subject and an ambient temperature of the subject. The method further includes detecting a power of the measurement retro-reflected light beam and detecting a power of the reference retro-reflected light beam. The method further includes calculating a measurement ratio of the detected power of the measurement retro-reflected light beam and the first power and calculating a reference ratio of the detected power of the reference retro-reflected light beam and the second power.

Abstract: A method for detecting levels of viscosity of a sample of whole blood, comprising the steps of providing a curve of the kinetics of optical density of the sample of whole blood, said curve comprising a first point (b) having a value of optical density and a point (c) of minimum value of said optical density; determining the value of the drop between the value of optical density in correspondence with the point (b) and the minimum value of optical density in correspondence with the point (c); obtaining information, based on the value of drop, on the value of viscosity of said sample of whole blood, wherein a low value of the drop of optical density corresponds to a higher level of viscosity of the sample of blood and a high value of the drop corresponds to a lower level of viscosity of the sample of blood.

Abstract: The present invention relates to a measuring device to determine the size, size distribution and/or concentration of nanoscopic particles or hollow spaces in a measuring sample, the degree of opacity of such measuring samples, or the degree of roughness of surfaces by determining the wavelength and scattering angle dependent intensities of a measuring radiation scattered on a measuring sample, comprising a retaining device for a measuring sample to be measured, a detector, comprising at least one detector inlet, an evaluation unit and at least two radiation sources, which are respectively at a distance from each other and at a distance from the measuring sample, which comprise a multiple wavelength spectrum or a continuous spectrum, and the radiation intensities of which are adjustable and/or determinable, wherein via the radiation sources one ray bundle can in each case be emitted in an essentially parallel beam in the direction of a measuring sample, and wherein the ray bundles which can be directed onto th

Abstract: The invention relates to a measurement apparatus, and method, for analysis of particles in a liquid sample, the apparatus comprising: an image acquiring device, an image analyser, a holder arranged to hold a sample retaining device, and a light refractor positioned between said image acquiring device and said holder; whereby at least one of the image acquiring device, the light refractor and the holder is movable by means of a piezoelectric motor, thereby moving a focus plane within the sample retaining device when it is held by the holder whereby the image acquiring device is adapted to acquire a plurality of images of said sample at different focus planes within the sample retaining device; wherein the image analyser is arranged to analyse at least one acquired image for identifying which of the particles are imaged in focus, and analysing those particles which have been identified as being imaged in focus.

Abstract: A measuring cell for receiving a blood sample is designed such that it can be transilluminated with a light source. The light source and a means for determining the luminous intensity corresponding to the light source can be arranged on the measuring cell for determining the luminous intensity of the light of the light source emerging from the measuring cell, wherein the measuring cell has constant, predefined properties with respect to the light of the light source, so that the blood oxygen content of the blood sample can be detected on the means for determining the luminous intensity due to a change of the luminous intensity of the light of the light source.

Abstract: An optical measurement device for measuring an optical appearance of a surface of a sample, in particular the surface of a human skin, wherein the optical measurement device comprises: a first illumination device (16) for illuminating the surface (14) with a first illumination beam (22), wherein the first illumination beam (22) is incident at a first angle of incidence (38) onto the surface (14); and a detection device (28) for detecting a response beam (22), wherein the response beam (42) is a response of the sample (12) to the first illumination beam (22), comprising at least one screen (27) for intercepting the response beam (42) and at least an image detection component (29). The optical measurement device (10) comprises a second illumination device (18), wherein the second illumination device (18) is providing a second illumination beam (24) with a second angle of incidence (54) at the surface (14), wherein the first angle of incidence (38) is different from the second angle of incidence (54).

Abstract: A method for measuring the concentration of a compound in the blood of a part of a subject is provided. An invasive or non-invasive sample of blood may be used for this determination. Also provided is a device for measuring the concentration of a compound in the blood of a subject. The device comprises a source of electromagnetic radiation, a holder, a detector and a processing system.

Abstract: A body fluid constituents measurement device, which performs measurement under a setting where light intensity of the light-emitting element is suitably stabilized, is provided.

Abstract: A sample acquiring device for volumetric enumeration of thrombocytes in a blood sample is provided which comprises a measurement cavity for receiving a blood sample. The measurement cavity has a predetermined fixed thickness. The sample acquiring device further comprises a reagent, which is arranged in a dried form on a surface defining the measurement cavity. The reagent comprises a haemolysing agent for lysing red blood cells in the blood sample, and optionally a staining agent for selectively staining thrombocytes in the blood sample. A system comprises the sample acquiring device and a measurement apparatus. The measurement apparatus comprises a sample acquiring device holder, a light source, and an imaging system for acquiring a digital image of a magnification of the sample. The measurement apparatus further comprises an image analyser arranged to analyse the acquired digital image for determining the number of thrombocytes in the blood sample.

Abstract: A cuvette with at least one sealing element and two transparent elements is provided where the latter are arranged at a distance from one another and define two opposing boundary faces of a sample channel and the sealing element defines side walls of the sample channel as a result of which the sample channel is formed as a channel that is closed in the longitudinal direction with an inlet opening and an outlet opening. At least one spacer is provided which keeps the transparent elements at a distance from one another. At least one of the two transparent elements has a projection which extends towards the other transparent element and forms a boundary surface of the sample channel such that the height of the sample channel is less than the height of the at least one spacer.

Abstract: A disposable blood test kit inserted into an instrument for measuring the blood cell deformability is provided to avoid a washing process during a blood test. The instrument comprises a disposable blood test kit (20) for directly containing the blood sample, a light emitting unit (10) disposed above the disposable blood test kit (20), and a measurement unit (30) for measuring the blood cell deformability. The disposable blood test kit (20) comprises a blood sample pot (21) for containing the blood sample, a slit channel (22) made of a transparent material, and a tiny waste blood pot (23) for collecting the tested blood sample. A differential pressure is applied to the disposable blood test kit (20) to make the stagnant blood sample flow through the slit channel (22) and to collect the tested blood sample at the tiny waste blood pot (23).

Abstract: There is provided a microchip that is formed of a first substrate having a surface with a groove and a second substrate joined together and has a fluid circuit in the form of a cavity defined by the groove and a surface of the second substrate closer to the first substrate. The fluid circuit at least includes a detection portion having an optical path for transmitting light. The microchip includes at least one of a step defined by a groove formed in contact with at least one side surface of a groove of the first substrate that defines the optical path and a recess provided in the second substrate at a position opposite to the step.

Abstract: The present invention relates to the analysis of cytological material. Specifically, the invention relates to stains and methods of producing the stains, methods of staining cells for cytological or histological analysis to contrast the nuclear portion of the cell from the cytoplasmic portion, and systems and methods for illuminating a cytological sample. The analysis can be automated or manual.

Abstract: An imaging method and system are presented for use in sub-wavelength super resolution imaging of a subject. The imaging system comprises a spatial coding unit configured for collecting light coming from the scanned subject and being spaced from the subject a distance smaller than a wavelength range of said light; a light detection unit located upstream of the spatial coding unit with respect to light propagation from the object, and configured to define a pixel array and a spatial decoding unit, which is associated with said pixel array and is configured for applying spatial decoding to a magnified image of the scanned subject, thereby producing nanometric spatial resolution of the image.

Abstract: An approach to detecting microorganisms in blood uses the changes of hemoglobin and the physical and chemical properties of blood to detect the presence of microorganisms in blood. Spectrophotometric measurements are taken several wavelengths across the UV-Vis-NIR portion of the electromagnetic spectrum, and a deconvolution is performed quantitatively to interpret distinct spectral characteristics of blood enabling the detection of microorganisms.

Abstract: A device has a source for emitting near infrared radiation into cerebral tissue, a sensor for detecting radiation exiting from the tissue, and an evaluation unit which detects the exiting radiation as an input signal having pulsatile and non-pulsatile components and is programmed to determine the concentration of an injected indicator in the tissue from the non-pulsatile signal component, iteratively determine an inflow function characterizing cerebral blood flow by varying a mean transit time until reaching a stop criterion, determine indicator concentration relative to cerebral blood volume from the inflow function and the pulsatile signal component, calculate cerebral blood volume by dividing indicator concentration in the tissue by indicator concentration relative to cerebral blood volume, calculate cerebral blood flow by dividing the cerebral blood volume by the mean transit time when the stop criterion has been reached, and scale the inflow function using values determined from the pulsatile signal comp

Abstract: The present invention provides a detecting element which can stably detect a substance with high sensitivity; a detecting device therefor; and a detecting method therefor. The detecting element and the detecting device according to the present invention have a plurality of planes having a plurality of mutually-separated metallic structures arranged thereon. The detecting method according to the present invention includes making a detecting light irradiate the detecting element so that the light can intersect a plurality of the planes. Thereby, the detecting light is more frequently absorbed in the vicinity of the metallic structure and the detecting device can stably detect a slight change of a spectrum originating from a trace change of a refractive index occurring in the vicinity of the metallic structure, with the high sensitivity.

Abstract: There is provided a method and device for remote sampling, preparation and optical interrogation of a sample using light scattering and light absorption methods. The portable device is a filtration-based device that removes interfering background particle material from the sample matrix by segregating or filtering the chosen analyte from the sample solution or matrix while allowing the interfering background particles to be pumped out of the device. The segregated analyte is then suspended in a diluent for analysis. The device is capable of calculating an initial concentration of the analyte, as well as diluting the analyte such that reliable optical measurements can be made. Suitable analytes include cells, microorganisms, bioparticles, pathogens and diseases. Sample matrixes include biological fluids such as blood and urine, as well as environmental samples including waste water.

Abstract: An optical coagulation monitor and the method of monitoring blood coagulation status are disclosed. The method includes positioning a sample probe containing an optical fiber within a circulating blood; transmitting a low-coherence light through the optical fiber into the blood; detecting dynamic light scatter signals generated by the blood within a coherence volume and received through the optical fiber; analyzing the dynamic light scatter signals in comparison to a predetermined coagulation criterion; and reporting the coagulation status of the blood. The method can be used for monitoring blood coagulation status in vivo or in vitro in real time. Further disclosed is a method of determining blood clotting time in vitro using the optical coagulation monitor.

Abstract: An optical technique to improve the imaging of a target inside suspensions of scattering particles includes the illumination of the scattering particles with circularly polarized light. The backscattered light from the host medium preserves the helicity of incident light, while the backscattered light reflected from the target is predominated with light of opposite helicity. Based on the observed helicity difference in the emerging light that originated at the target and that backscattered from the medium, the present optical technique improves the image contrast using circular polarization. This approach makes use of polarization memory which leads to the reflected light from the target accompanied by weak diffusive backscattered light. Using the present technique, improved imaging of the artery wall is achieved and plaque composition can be assessed through a blood field associated with the artery.

Abstract: The present invention relates to devices and methods for the qualitative and/or quantitative detection of particles. In particular, the invention relates to devices for the detection of particles, comprising a reaction chamber formed within a chamber body between a first surface and a second surface, wherein the second surface is located opposite to the first surface, and one or more displacers, wherein the distance between the first surface and the second surface is variable via the one or more displacers at least in one or more parts of the surface area of the first surface and/or the second surface.

Abstract: Embodiments of the invention relate to a light illumination funnel. The funnel includes a first opening positioned to receive an incoming light source, a second opening positioned opposite the first opening and with a diameter smaller than the first opening and inner reflective walls, in contact with the first opening and second opening. The funnel has a half angle of less than 25 degrees. Embodiments also relate to a light collection funnel and an apparatus utilizing both a light illumination funnel and light collection funnel.

Abstract: A flow-through tank 300 is suitable for an optical device for the counting and/or differentiation of leucocytes in an automatic blood analysis apparatus 1. The tank has an analysis zone 304, in which the section of the tank has at least one transverse dimension between 1 and 5 millimetres. It can advantageously be produced, at least partially, from an injected plastic material.

Abstract: An apparatus with a combination of a point light source and a single lens is provided. The present apparatus includes a point light source, a photodetector and a lens. The lens is placed in the same side of the point light source and the photodetector in order that the light emitting from the point light source is focused onto a target area of an object through the lens. The reflected light from the target area is focused onto the photodetector through the lens. The present apparatus can qualitatively and quantitatively monitor a content of a specific component of a tested solution. The geometric relationship of the point light source, the photodetector and the single lens can improve a measuring resolution of the present apparatus.

Abstract: [Problems] A disposable cell counting board in which a space formed by a counting board body and an upper plate is fixed in advance, and which does not require assembling by a cell counting worker, and which can be mass-produced at low costs, is provided. [Means for Solving Problems] The cell counting board comprises a main body and a cover plate attached to the main body. The main body comprises a planar lands positioned at a lower position by a predetermined distance with respect to the top face of the other part than the lands, a counting sections provided at the lands, and four projection sections in the vicinity of the lands for positioning and fixing the cover plate above the lands. The cover plate has engagement holes formed at locations corresponding to the projection sections. A space of the predetermined distance, 0.

Abstract: The present invention is to present a sample analyzer capable of automatically stabilizing the laser diode in multi-mode oscillation. A sample analyzer 1 comprises: a laser diode (LD) 501d for irradiating a sample with laser light; a photodiode (PD) 501e for detecting amount of light emitted from the LD 501d; a APC circuit 501b for outputting a direct current to be supplied to the LD 501d such that the amount of light emitted from the LD 501d is maintained at a predetermined amount, based on the amount of light detected by the PD 501e; a high frequency oscillation circuit 501f for superimposing a high frequency component on the direct current outputted from the APC circuit 501b; and a high frequency automatic adjustment circuit 501c for controlling amplitude of the high frequency component outputted from the high frequency oscillation circuit 501f according to magnitude of the direct current outputted from the APC circuit 501b such that the LD 501d oscillates in a multi-mode.

Abstract: A system and method is disclosed which relates to reading test strips. The method may include reading and storing initial values of a front photodiode and a rear photodiode, reading current values of the front and rear photodiodes, detecting at least one change between initial and current values in the front or the rear photodiodes, comparing the detected value change of one of the photodiodes with the value of the other photodiode, and determining a condition of the test strip in response to the resulting comparison.

Abstract: A measuring apparatus is provided with a light source (4), a first light-receiving element (5) and a second light-receiving element (6) which output signals corresponding to light intensity, a calculating part (12) and a memory part (13). The first light-receiving element (6) and the light source (4) are arranged so that transmitted light emitted from the light source and passed through a sample is received by the first light-receiving element (5). The second light-receiving element (6) is arranged so as to receive light other than the transmitted light emitted from the light source (4). In the memory part (13), a correlation between the output value of the first light-receiving element (5) and the output value of the second light-receiving element (6) when light is emitted from the light source (4) in a state where the sample is not present is stored.

Abstract: The present invention comprises methods and systems that use acoustic radiation pressure.

Abstract: A method for discriminating particle groups comprises generating, by a particle analyzer, a particle characteristic distribution histogram in which the abscissa indicates respective channels for representing the characteristics of the particles, and the ordinate indicates the particle count; setting a valid area selection height in the particle characteristics distribution histogram; and generating an equivalent negative histogram based on the set height and the particle characteristic distribution histogram.

Abstract: A liquid measuring device and an automatic analyzer which employs a resonance phenomenon of sound waves to detect an amount of a liquid reserved in a vessel with an opening are provided. The liquid measuring device includes a sound source that emits sound waves toward the opening, a control device that controls a frequency of the sound waves emitted by the sound source, a wave receiver that measures a resonance generated as the sound waves emitted by the sound source causes an air column in the vessel to resonate, a detector that detects a resonance frequency of the resonance measured by the wave receiver, and a liquid-amount determination unit that determines, based on the detected resonance frequency, an amount of the liquid reserved in the vessel.

Abstract: The present invention discloses an optical sensor for measuring blood gas, used to measure gas concentration in a liquid, comprising: an indicator solution; a first conduit for filling with the indicator solution wherein the first conduit passes through the liquid and the gas in the liquid can diffuse into the first conduit to react with the indicator solution so as to change the color of the indicator solution; a second conduit for receiving the reacted indicator solution in the first conduit; and a light emitter and a photodetector provided in opposition to each other at the two sides of the second conduit wherein the light emitter emits light towards the second conduit and the photodetector receives the light passing through the second conduit and the reacted indicator solution and thereby outputs a sensing signal depending on the received light intensity.

Abstract: A reagentless whole-blood analyte detection system that is capable of being deployed near a patient has a source capable of emitting a beam of radiation that includes a spectral band. The whole-blood system also has a detector in an optical path of the beam. The whole-blood system also has a housing that is configured to house the source and the detector. The whole-blood system also has a sample element that is situated in the optical path of the beam. The sample element has a sample cell and a sample cell wall that does not eliminate transmittance of the beam of radiation in the spectral band.

Abstract: The optical analysis system (20) is arranged to determine an amplitude of a principal component of an optical signal. The optical analysis system (20) comprises a multivariate optical element (5, 6) for weighing the optical signal by a spectral weighing function and a detector (7, 8) for detecting the weighed optical signal. The optical signal comprises the principal component and a further component which was not accounted for when designing the spectral weighing function. Therefore, the detected weighed optical signal comprises a part relating to the amplitude of the principal component and a further part relating to a further amplitude of the further component. The optical analysis system (20) further comprises a modulator element (13) for modulating the detected weighed optical signal.

Abstract: The invention relates to embodiments of a method and a system for monitoring the correct positioning of a test element in a test element receptacle of an analysis unit, the test element carrying a sample to be analyzed by the analysis unit. Using a delimiting element, responsive signals resulting from irradiating an analysis region on the test element are effectively prevented from impinging upon a signal detector when the analysis region is in an incorrect position relative to the analysis unit. The delimiting element is provided with a light-opaque region and a light-transmissive region, and the light-opaque region is positioned such that responsive signals impinge upon it rather than the light-transmissive region when the analysis region is in an incorrect position.

Abstract: The invention concerns a method for detecting the amounts of substances that may disturb chemical analysis performed by an analyzer for clinical chemistry. The presence and concentration of hemoglobin, bilirubin and lipemia are detected by measuring the absorbance or reflectance on at least two, preferably six, different wavelengths over the measured spectrum. The measurements are performed at two wavelengths for each substance, preferably on the absorbance peaks of the specific substance and on the root of the specific peaks. Since the three substances mentioned above each have at least one peak in the spectrum, the measurement is done on three peaks and three root positions respectively when three substances have to be measured.

Abstract: A sensor designed to determine the amount and concentration of analyte in a sample having a volume of less than about 1 ?L. The sensor has a working electrode coated with a non-leachable redox mediator. The redox mediator acts as an electron transfer agent between the analyte and the electrode. In addition, a second electron transfer agent, such as an enzyme, can be added to facilitate the electrooxidation or electroreduction of the analyte. The redox mediator is typically a redox compound bound to a polymer. The preferred redox mediators are air-oxidizable. The amount of analyte can be determined by coulometry, amperometry, voltammetry, and potentiometry. The invention can be used to determine the concentration of a biomolecule, such as glucose or lactate, in a biological fluid, such as blood or serum. An enzyme capable of catalyzing the electrooxidation or electroreduction of the biomolecule is provided as a second electron transfer agent.

Abstract: Innovative techniques that result in a better signal-to-noise ratio for spectrographic analysis of substances in a target than conventional techniques. In these techniques, light illuminates a target with at least some of the light penetrating the target. At least a portion of the light that penetrates the target is collected from a region on the target's surface that is not directly illuminated. Preferably, at least a majority of the collected light is light that penetrates the target. Also preferably, the light that illuminates the target is in a pattern that partially but not completely surrounds the region from which the portion of the light that penetrates the target is collected. A spectrum of at least a portion of the collected light is analyzed.