Abstract: Disclosed is a lateral flow quantitative assay method which can measure one or more analyte species at the same time, with high sensitivity. Also, the present invention relates to a strip which can measure one or more analyte species at the same time, with high sensitivity and a package in which the strip is integrated with a laser-induced surface fluorescence detector. The present invention can quantify multiple analytes with a minimum detection limit of pg/ml. Therefore, the present invention provides an advantage capable of quantifying a plurality of analytes at the same time using a simple lateral flow assay strip.

Abstract: An optical detection system that utilizes an electroluminescent (EL) illumination source is provided. Unlike illumination sources used with some conventional optical detection systems, an EL device is relatively homogeneous and diffuse, and thus may provide uniform illumination to the test sample. In addition, the emitted light intensity of the EL device may be easily controlled by simply varying the voltage or the frequency of the applied current. The relatively flexibility of EL devices may also allow them to be readily incorporated into a chromatographic-based assay device for detecting the presence or absence of an analyte within a test sample.

Abstract: The present invention relates to a technique for analyzing the concentration of a specific component in a sample liquid, such as a method for analyzing a sample. The analyzing method includes a first detection step for irradiating light from a light source (50) onto a reaction system to detect a response from the reaction system (56) as a first detection result. The reaction system contains a sample liquid and a reagent. The method also includes a second detection step for irradiating light onto a reference board (54) to detect a response from the reference board as a second detection result. The response from the reference board under light irradiation is dependent on wavelength. The method further includes a calculation step for calculating the concentration of the specific component in the sample liquid based on the first and second detection results.

Abstract: Methods and apparatus, including computer program products, implementing and using techniques for collecting optical data pertaining to one or more characteristics of a sample. The apparatus has a light source, one or more illumination optical elements, a scanner, one or more collection optical elements, and a device forming an aperture that limits detection of light from the sample. The illumination optical elements direct a light beam from the light source onto the sample. The scanner scans the light beam across the sample. The collection optical elements collect light from the sample and transmit the collected light to a detector. None of the collection optical elements are included among the illumination optical elements. The device forming an aperture limits detection of light from the sample to light associated with a limited vertical depth within the sample, and is one of the collection optical elements.

Abstract: In a fluorescence detection method: each of one or more biological specimens is irradiated with excitation light while a substrate disk is rotated, where the one or more biological specimens are labeled with a fluorescent material and fixed on the substrate disk. Fluorescence which is emitted from each of the one or more biological specimens is detected when a predetermined time elapses since the biological specimen is irradiated with the excitation light.

Abstract: A fluid content monitor including a cuvette, a calorimeter adapted to generate a signal indicative of contents of a fluid sample contained in the cuvette, a container for holding a reagent, and a pump assembly for delivering reagent from the container to the cuvette. The pump assembly includes a tube extending from the container to the cuvette, check valves preventing reverse flow in the tube, and a hammer driven by a solenoid for repetitively compressing the tube to pump reagent to the cuvette. The cuvette can be removed for cleaning and replacement.

Abstract: An automated analyzer for performing multiple diagnostic assays simultaneously includes multiple stations in which discrete aspects of the assay are performed on fluid samples contained in reaction receptacles. The analyzer includes stations for automatically preparing a sample, incubating the sample, preforming an analyte isolation procedure, ascertaining the presence of a target analyte, and analyzing the amount of a target analyte. An automated receptacle transporting system moves the reaction receptacles from one station to the next. A method for performing an automated diagnostic assay includes an automated process for isolating and amplifying a target analyte, and, in one embodiment, a method for real-time monitoring of the amplification process.

Abstract: An indicator that reacts with at least one gaseous compound in such a way that the color of the indicator is changed. The indicator is a layer formed on a substrate and including metallic silver and/or metallic copper.

Abstract: Described herein is an analyte detection device and method related to a portable instrument suitable for point-of-care analyses. In some embodiments, a portable instrument may include a disposable cartridge, an optical detector, a sample collection device and/or sample reservoir, reagent delivery systems, fluid delivery systems, one or more channels, and/or waste reservoirs. Use of a portable instrument may reduce the hazard to an operator by reducing an operator's contact with a sample for analysis. The device is capable of obtaining diagnostic information using cellular- and/or particle-based analyses and may be used in conjunction with membrane- and/or particle-based analysis cartridges. Analytes, including proteins and cells and/or microbes may be detected using the membrane and/or particle based analysis system.

Abstract: Screening assays and methods of performing such assays are provided. In certain examples, the assays and methods may be designed to determine whether or not two or more species can associate with each other. In some examples, the assays and methods may be used to determine if a known antigen binds to an unknown monoclonal antibody.

Abstract: An optochemical sensor element 9 measures gaseous or dissolved analytes, in particular of oxygen. The sensor element 9 includes a fluorophor 25 that is immobilized in a polymer matrix 23. The polymer matrix itself is formed of a polymer with a non-aromatic backbone. The sensor element 9 is useful in a measuring device.

Abstract: Enhancement of fluorescence emission from fluorophores bound to a sample and present on the surface of two-dimensional photonic crystals is described. The enhancement of fluorescence is achieved by the combination of high intensity near-fields and strong coherent scattering effects, attributed to leaky photonic crystal eigenmodes (resonance modes). The photonic crystal simultaneously exhibits resonance modes which overlap both the absorption and emission wavelengths of the fluorophore. A significant enhancement in fluorescence intensity from the fluorophores on the photonic crystal surface is demonstrated.

Abstract: An object of the present invention is to suppress variations in measurement values when measuring a specific binding reaction between a physiologically active substance and a tested substance using a surface plasmon resonance measurement device, so that binding detection data with high reliability is obtained. The present invention provides a method for measuring a change in surface plasmon resonance, which comprises: using a surface plasmon resonance measurement device comprising a flow channel system having a cell formed on a metal film and a light-detecting means for detecting the state of surface plasmon resonance by measuring the intensity of a light beam totally reflected on the metal film; and exchanging the liquid contained in the above flow channel system, wherein a major axis of the metal film is 0.

Abstract: Provided photo-decontamination catalyst material comprising an optically active molecule embedded/incorporated/bridged in a periodic mesoporous organosilica (PMO). The optically active molecule is a typically a fluorophore or chromophore, more specifically, a porphyrin or phthalocyanine. The periodic mesoporous organosilica can be a template directed molecularly imprinted periodic mesoporous organosilica. The PMO material incorporating an optically active molecule is useful as a catalyst in photo-decontamination applications, as well as a detection element for stand-off point detection system.

Abstract: A microsphere-based analytic chemistry system is disclosed in which self-encoding microspheres having distinct characteristic optical response signatures to specific target analytes may be mixed together while the ability is retained to identify the sensor type and location of each sensor in a random dispersion of large numbers of such sensors in a sensor array using an optically interrogatable encoding scheme. An optical fiber bundle sensor is also disclosed in which individual microsphere sensors are disposed in microwells at a distal end of the fiber bundle and are optically coupled to discrete fibers or groups of fibers within the bundle. The identities of the individual sensors in the array are self-encoded by exposing the array to a reference analyte while illuminating the array with excitation light energy.

Abstract: Periodic mesoporous organosilicas (PMO) which incorporate an optically active molecule into the material for use as an optical indicator of target binding. This material combines the stability, selectivity, and high density of binding sites characteristic of the PMO with the sensitivity and selectivity of the optically active molecule. The material undergoes a change when exposed to a sample containing a target molecule. The change can be observed by visual inspection or through the use of fluorescence spectra.

Abstract: The invention is a method of measuring oxygen concentration in a package having an oxygen sensitive product disposed therein. The method includes exposing a luminescent compound that is disposed in an interior of the package to light having a wavelength that is absorbed by the luminescent compound so that the luminescent compound is promoted into an excited state. When the exposure of the light is terminated, the excited luminescent compound emits light that is detectable by a detector positioned outside of the package. The intensity of the emitted light is inversely proportional to the oxygen concentration and is used in conjunction with mathematical function that describes the luminescent intensity of the luminescent compound as a function of oxygen concentration and temperature to calculate the oxygen concentration. The method may be used to verify and track the oxygen concentration of a package as it moves through a distribution system.

Abstract: A method to efficiently measure the oxygen content of both the headspace and fluid within a hermetically sealed container. A container is pierced using a hollow needle with the interior space sealed from the outside and the tip of said hollow needle removed, and the interior space is made continuous with the headspace within the container. A probe of a fluorescent oxygen concentration meter is inserted through the hollow needle to the interior of the container, positioned in the headspace within the container, and the oxygen concentration of the headspace 3 is measured. The probe is inserted further so that the fluorescent material is submerged in the fluid inside the container, and the dissolved oxygen concentration inside the fluid is measured.

Abstract: Integrated photoluminescence (PL)-based chemical and biological sensors are provided comprising a photodetector (PD), a long-pass filter, an excitation source, and a sensing element, all based on thin films or structures. In one embodiment the light source is an organic light emitting device (OLED) and the sensing element is based on thin films or solutions in microfluidic channels or wells. The PD and optical filters are based on thin film amorphous or nanocrystalline silicon and related materials. In another embodiment, sensor components are fabricated on transparent substrates, which are attached back-to-back to generate a compact, integrated structure.

Abstract: The present invention provides methods for the identification and use of diagnostic markers for differential diagnosis of diseases. In a various aspects, the invention relates to methods and compositions able to determine the presence or absence of one, and preferably a plurality, of diseases that exhibit one or more similar or identical symptoms. Such methods and compositions can be used to provide assays and assay devices for use in determining the disease underlying one or more non-specific symptoms exhibited in a clinical setting.

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 supplies 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 platform and method for mimicking the environment within a cell is provided. The platform includes a microfluidic device defining a chamber. At least one hydrogel post is positioned within the chamber of the microfluidic device. Each hydrogel post defines a corresponding pore for receiving a first molecule therein. Second molecules are introduced into the pores of the hydrogel posts and the interactions between the first and second molecules are observed.

Abstract: An automated apparatus and method for analyzing liquid samples by forming discrete sample aliquots (boluses) in an elongated conduit which contains a hydrophobic carrier liquid. Aliquots may be analyzed by adding at least one reagent to the sample aliquot that reacts selectively with an analyte contained therein. The reaction product, which is selective for the analyte of interest and proportional to its concentration, is measured with an appropriate detector. Intrinsic sample properties of the sample may also be measured without the need for adding chemical reagents. The invention enables simple and accurate testing of samples using time honored wet-chemical analysis methods in microliter volume regimes while producing remarkably small volumes of waste.

Abstract: The invention relates to biosensors, methods for obtaining them and their use for detecting, assaying or locating, in direct immunofluorescence, a ligand such as an antigen or hapten, in a heterogeneous population. The biosensor includes (i) at least one fragment of a receptor which is protein in nature, capable of binding to a ligand via an active site, where at least one amino acid residues of the fragment located in the proximity of the active site is naturally present in the form of a cystein (Cys) residue, or is substituted with a Cys residue, and (ii) a fluorophore coupled to the Cys residue.

Abstract: An assay system having a channel bounded by first and second reflective surfaces adapted to accommodate a fluid material therebetween and defining a plurality of regions in an array between those surfaces with each region defining a resonant cavity and adapted to receive a capturing material on a surface thereof whereby a source of radiation illuminates each region to provide a standing wave of radiation of within the cavity indicative of binding of said capturing agent to material under investigation, a binding thereof being detected in response to radiation from each cavity indicative of a change in the standing wave pattern.

Abstract: The present invention provides, a system and method for unobtrusively determining water content within a fuel cell. One embodiment of a system in accordance with the present invention includes a fuel cell body including an ionomeric membrane, water and a fluorophore contained therein. The system further includes a medium for permitting light transfer therein, such as an optical fiber, having opposing ends, wherein one end contacts or is disposed in a portion of the ionomeric membrane and the other end extends from the fuel cell body. The other end is preferably divided into at least two portions, one portion being operatively associated with a light source, and another portion being operatively associated with a spectrometer.

Abstract: A surface plasmon resonance assay apparatus is loaded with a sensor unit. A sensing surface of a thin film detects reaction of a sample. A dielectric prism is overlaid with the thin film to constitute an interface. A reflection angle upon occurrence of attenuated total reflection of the illuminating light is changeable according to reaction of the sample on the sensing surface. Protecting panels are disposed to face outer surfaces of the prism, for covering and protecting at least partially the outer surfaces. A first window in one of the protecting panels is positioned on a path of the illuminating light traveling for incidence on the interface, for passing the illuminating light. A second window in one remaining protecting panel is positioned on a path of the illuminating light traveling upon reflection by the interface, for passing the illuminating light.

Abstract: Methods for differentially identifying cells in an instrument employ compositions containing a combination of selected antibodies and fluorescent dyes having different cellular distribution patterns and specificities, as well as antibodies and fluorescent dyes characterized by overlapping emission spectra which form non-compensatable spectral patterns. When utilizing the compositions described herein consisting of fluorescent dyes and fluorochrome labeled antibodies with overlapping spectra that cannot be separated or distinguished based upon optical or electronic compensation means, a new fluorescent footprint is established. This new fluorescent footprint is a result of the overlapping spectra and the combined cellular staining patterns of the dyes and fluorochrome labeled antibodies chosen for the composition. The new fluorescent footprint results in histogram patterns that are useful for the identification of additional cell populations or subtypes in hematological disease.

Abstract: A device and a method for measuring viscosity that includes attaching molecular rotors to a solid surface, exposing the solid surface to a fluid having a viscosity to be measured, and taking optical measurements to determine viscosity. The solid surface is preferably quartz, polystyrene or silicate glass, such as a fiber optic probe or a glass cuvette. The molecular rotors are of the type that includes an electron-donor group and electron-acceptor group that are linked by a single bond so that the groups may rotate with respect to one another, and that exhibit a fluorescence emission when rotation is hindered.

Abstract: The present invention provides sensors and methods for determination of an analyte. The analytes may be determined by monitoring, for example, a change in an optical signal of an emissive material upon exposure to an analyte. In some embodiments, the analyte and the emissive material may interact via a chemical reaction, or other chemical, biochemical or biological interaction (e.g., recognition), to form a new emissive species. In some cases, the present invention may be used for the detection of analytes such as explosives (e.g., RDX, PETN). Methods of the present invention may be advantageous in that the high sensitivity of luminescence (e.g., fluorescence) spectroscopy can allow for the reliable detection of small changes in luminescence intensity.

Abstract: The apparatus for deriving at least one property like turbidity or fluorescence of a sample liquid from measuring emitted light emitted from said sample liquid upon irradiation of said sample liquid with a probe light beam comprises a container for containing said sample liquid, said sample liquid forming a sample surface. It furthermore comprises a light source for generating said probe light beam directed, in an angle ?1?0° with respect to a sample surface normal, at said sample surface, and a detector adapted to detecting an intensity of said emitted light emitted through said sample surface out of said sample liquid generally along a first detection axis, said first detection axis forming an angle ?1?0° with a sample surface normal.

Abstract: The invention provides a luminescent based sensor having a luminescent material optically coupled to a substrate, and adapted to be used in a medium or environment such as water or air. A detector is provided to detect light that is emitted into the substrate by the material. The substrate is adapted to redirect light that is emitted into the substrate at angles with the range ?esc ? ? ? ?lsc where ?esc is the critical angle of the environment/substrate interface and ?lsc is the critical angle of the luminescent layer/substrate interface. Examples of possible configurations are described.

Abstract: The present invention relates to methods and compositions for measuring latent protein C in test samples, particularly patient samples. The methods and compositions described are sensitive for latent protein C, relative to activated protein C.

Abstract: This invention provides methods of using ion-detecting microspheres containing an ionphore and a chromoionphore in clinical laboratory instrumentation such as flow cytometry for sample analysis. In one embodiment, the microspheres are contacted with a flowing stream of a sample under conditions that allow the ion-selective ionophores to complex with the ions in the sample, and to cause deprotonation of the chromoionophore. The complexes are then exposed to an excitation wavelength light source suitable for exciting the deprotonated chromoionophore to emit a fluorescence signal pattern. Detection of the fluorescence signal pattern emitted by the deprotonated chromoionophore in microspheres containing the complexes allows for determination of the presence of the target ions in the sample. In one embodiment, lead ion-detecting microspheres are provided that can detect nanomolar levels of lead ions with response times on the order of minutes.

Abstract: The invention relates to a reagent and a process for the identification and counting of biological cells in a sample. This reagent comprises a cell lysing agent selected from at least one detergent in a concentration capable of specifically lysing a given type of cells in the sample, and a stain capable of marking the intracellular nucleic acids of the remaining unlysed cells. Application in particular for the identification and counting of cells using an automated analysis system based on flow cytometry.

Abstract: A membrane-based assay device for detecting the presence or quantity of an analyte residing in a test sample is provided. The device utilizes time-resolved fluorescence to detect the signals generated by excited fluorescent labels. Because the labels can have relatively long emission lifetime, short-lived background interference can be practically eliminated through delayed fluorescence detection. In addition, the resulting fluorescent reader can have a simple and inexpensive design. For instance, in one embodiment, the reader can utilize a silicon photodiode and a pulsed light-emitting diode (LED) to accurately excite labels and detect fluorescence on a membrane-based assay device without requiring the use of expensive components, such as monochromators or narrow emission band width optical filters.

Abstract: A method useful for the enumeration of cell populations in a biological sample includes the steps of reacting in a single reaction mixture a sample, a first antibody labeled with a fluorochrome having a first emission spectrum and an additional antibody. The first antibody binds to an antigenic determinant differentially expressed on leukocytes and non-leukocytes. The additional antibody binds to an antigenic determinant differentially expressed on mature and immature granulocytes or myeloid cells, and is labeled either with the first fluorochrome or an additional fluorochrome having an emission spectrum distinguishable from the first emission spectrum. The reaction mixture can be mixed with a nucleic acid dye having an emission spectrum that overlaps with one of the first or additional emission spectra. The reaction mixture may be treated with a lytic system that differentially lyses non-nucleated red blood cells and conserves leukocytes.

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: 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: Samples of materials used in industrial processes are analyzed to determine the concentration of certain materials of interest. The quantitative analysis of samples for these materials is provided without the need for manual methods such as titration. Indicators such as fluorescent dyes for which the intensity of fluorescence is indicative of the concentration of a material of interest are used. The dyes are made to fluoresce by means of a light source, and a photomultiplier or other detector capable of measuring light intensity detects the resulting fluorescence. The intensity of fluorescence in the sample is compared to the intensities of fluorescence produced by samples with known concentrations of the material of interest to determine the concentration of the material of interest of the sample.

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: Apparatus and method for treating a liquid sample stream including at least one analyte ion species and matrix ion species of opposite charge to said one analyte ion species. The liquid sample stream flows through a treatment channel. A carrier liquid stream including a matrix ion species capture material flows substantially parallel to the sample stream in the treatment channel forms a liquid interface between them. The matrix ion species diffuses through the interface to contact and become bound by the capture material in said carrier liquid.

Abstract: A method for counting megakaryocytes in a specimen is described. In the method, first, erythrocytes in the specimen are lysed and nucleic acid in the megakaryocytes is stained with a fluorescent dye, and thereby, a measurement sample is prepared. Next, the cells in the measurement sample are irradiated with excited light so that the forward scattered light, the side scattered light and the fluorescence, which are emitted from the cells, are detected. Megakaryocytes are identified on the basis of the detected forward scattered light, the fluorescence and the side scattered light. Then, the identified megakaryocytes are counted.

Abstract: Heterogeneous assays for different analytes in a single biological sample are performed simultaneously in a multiplexed assay that combines flow cytometry with the use of magnetic particles as the solid phase and yields an individual result for each analyte. The particles are distinguishable from each other by characteristics that permit them to be differentiated into groups, each group carrying an assay reagent bonded to the particle surface that is distinct from the assay reagents of particles in other groups. The magnetic particles facilitate separation of the solid and liquid phases, permitting the assays to be performed by automated equipment. Assays are also disclosed for the simultaneous detection of antibodies of different classes and a common antigen specificity or of a common class and different antigen specificities.

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: An apparatus and non-invasive method of measuring oxygen by exciting a luminescent compound disposed in a container and then measuring the intensity of the light emitted by the excited luminescent compound as it relaxes to the ground state. A plot of emission intensity as a function of time results in an exponential decay curve the area of which is inversely proportional to the oxygen concentration. The oxygen concentration can be determined over a wide temperature range by measuring the temperature of the container and the emission intensity and then applying the following equation: [O2]=(ATa(T)2+BTa(T)+CTa)(tau)2+(ATb(T)2+BTb(T)+CTb)(tau)+(ATc(T)2+BTc(T)+CTc) T is the measured temperature; tau is the area of the exponential decay curve; and ATa, BTa, CTa, ATb, BTb, CTb, ATc, BTc, and CTc are coefficients that are specific to the luminescent compound being examined.

Abstract: An electrochemiluminescence cell comprising an electrode capable of inducing an electrochemiluminescence-active species to electrochemiluminesce. The electrode is preferably made of rhodium, iridium or an alloy of platinum, rhodium or iridium alloyed with an alloy material comprising a transition element. The electrode may be used as counter electrode and/or as a working electrode in the electrochemiluminescence cell. The cell preferably includes a counter electrode and a support attached to the counter electrode. The support comprises a transparent portion in optical registration with the working electrode. The counter electrode may include one or more field extending elements interposed between the transparent portion and the working electrode. The field extending element is preferably a ladder or a grid.

Abstract: A microfluidic system comprising: at least one microfluidic channel, the inner surface of which is fluorinated or fluorous; and a pump for supplying a flow of an aqueous medium containing chemical reagents or assay components to said microfluidic channel. Preferably, the apparatus further comprises a supply of a non-aqueous medium which is compatible with the surface of the microfluidic channel but immiscible with the aqueous medium, such as a perfluorocarbon solvent, for forming a sheath around the flowing aqueous medium whereby the aqueous medium is suspended away from the surface of the microfluidic channel. Also provided are methods for carrying out a chemical reaction or a biological assay in the microfluidic systems of the subject matter disclosed herein.

Abstract: A sensor comprising a membrane containing bacteriorhodopsin. In one embodiment, the sensor comprises a layer of purple membrane between a first and a second electrode, wherein the electrodes are connected to a circuit such that a signal is produced when a charge is transferred across the membrane. In another embodiment, the sensor comprises a field effect transistor with a layer of purple membrane deposited on the gate. The layer of purple membrane may be further functionalized by adding fluorophores to the layer of purple membrane. The fluorophores may be deposited adjacent to the layer of purple membrane, or the fluorophores may be attached to the layer of purple membrane with linkages. The fluorophores or linkages between the fluorophores and the purple membrane may be functionalized with receptors to produce sensors for targeted chemical or biological species.

Abstract: A Method for identifying one or a small number of molecules, especially in a dilution of ?1 ?M, using laser excited FCS with measuring times ?500 ms and short diffusion paths of the molecules to be analyzed, wherein the measurement is performed in small volume units of preferably ?10?14 l, by determining material-specific parameters which are determined by luminescence measurements of molecules to be examined. The device which can be preferably used for performing the method according to the invention is a per se known system of microscope optics for laser focusing for fluorescence excitation in a small measuring compartment of a very diluted solution and for imaging the emitted light in the subsequent measurement through confocal imaging wherein at least one system of optics with high numerical aperture of preferably ?1.2 N.A.