Abstract: Photo-aging monitoring of light-based chemical indicators that experience performance degradation as the cumulative amount of light exposure from measurement and/or reference illumination increases from usage. Differing regions on a chemical indicator are illuminated with measurement illumination light of differing exposures, for example, higher brightness, longer exposure times, or both. Readings from the differing regions are compared with known aging information for the chemical indicator at issue to determine a confidence factor for the measurements. The confidence factor can be used to control various actions relating to measurements acquired from the chemical indicators, such as compensating measurement readings for photo-aging, assigning confidence levels to measurement readings, and issuing alerts to users when photo-aging exceeds one or more predetermined thresholds.

Abstract: A method to identify a compound of interest includes the step of subjecting a sample to a plurality of colorimetric spot tests to yield a plurality of resultant test colors. The resultant test colors are compared with reference colors to define a set of sample reference colors. Indexed reference color sets indexed for the compound of interest are provided. The indexed reference color sets are searched with one or more of the sample reference colors for a match with the set of sample reference colors. The identity of the sample as the compound of interest is then determined. A device and a system to identify compounds of interest are also disclosed.

Abstract: A device for identifying infection by the malaria parasite includes a microfluidic device having an inlet and an outlet and a diagnostic channel interposed between the inlet and the outlet. The diagnostic channel includes a contact surface and a sample pump configured to pump a RBC-containing sample into the inlet. The contact surface may be at least one of hydrophilic and roughened. Malaria infected RBCs (miRBCs) interact with the contact surface and become immobilized thereon whereas non-infected RBCs continue to flow downstream in the diagnostic channel.

Abstract: Three-dimensional microfluidic devices including by a plurality of patterned porous, hydrophilic layers and a fluid-impermeable layer disposed between every two adjacent patterned porous, hydrophilic layers are described. Each patterned porous, hydrophilic layer has a fluid-impermeable barrier which substantially permeates the thickness of the porous, hydrophilic layer and defines boundaries of one or more hydrophilic regions within the patterned porous, hydrophilic layer. The fluid-impermeable layer has openings which are aligned with at least part of the hydrophilic region within at least one adjacent patterned porous, hydrophilic layer. Microfluidic assay device, microfluidic mixer, microfluidic flow control device are also described.

Abstract: Labels and methods of producing labels for use in clinical, analytical and pharmaceutical development assays are provided. Labels may comprise shape-encoded particles which may be coupled to ligands such as DNA, RNA and antibodies, where different shapes are used to identify which ligand(s) are present. Labels may also comprise reflectors, including retroreflectors and retroreflectors susceptible to analyte-dependent assembly for efficient homogeneous assays.

Abstract: The present invention provides a system for analyzing a sample liquid comprising a test tape having a plurality of test elements, a tape transport device which successively transports the test elements to a sample application site while advancing the tape, and a measuring device which scans the test elements loaded with sample liquid at a measuring site. The measuring site is located at a distance from the sample application site in the direction of tape movement. The tape transport is interrupted in order to exactly position a wetted area of the test elements carrying a sample liquid at the measuring site by means of a positioning device that responds to the presence of sample liquid on the test element.

Abstract: Compositions that include bis(glyoxime)-transition metal complexes bound to metal oxide solid supports are provided. In some embodiments the compositions include nickel dimethylglyoxime and the metal oxide supports can be alumina or silica. These compositions can be used to make a colorimetric moisture-indicating sensor that changes visible reflection spectrum quantitatively and reversibly according to the amount of moisture in contact with the sensor. Also provided is a method of detecting moisture using the provided compositions.

Abstract: A method of cryopreserving sperm cells which may include cooling the quantity of sperm cells to a holding temperature, maintaining the sperm cells substantially at the holding temperature for a period, and supercooling the sperm cells by cooling the sperm cells at a first cooling rate to a temperature that approaches a critical temperature zone at which ice crystal formation and changes in osmotic pressure damage sperm cells and then cooling the sperm at a second cooling rate faster than said first cooling rate through said critical temperature zone.

Abstract: Microfluidic devices, assemblies, and systems are provided, as are methods of manipulating micro-sized samples of fluids. Microfluidic devices having a plurality of specialized processing features are also provided.

Abstract: The present invention provides a method for determining sickle-cell zygosity in a subject. The method involves forming a first solution which includes a sample from the subject, a phosphate buffer, a detergent, and a reducing agent and subjecting the first solution to centrifugation to form a second solution and a supernatant; and taking a color reading of the supernatant and of the second solution; optionally filtering the second solution to form a filtrate and a precipitate, and optionally measuring the amount of the precipitation and the absorbance of the filtrate or taking a color reading of the filtrate.

Abstract: The present invention relates to a color-changing material and to a multiple-component material that includes a color-changing composition. The color-changing materials and color-changing compositions are capable of changing color in order to indicate a change in condition, such as a change in pH. The color-changing materials and color-changing compositions include a hydrogel-forming composition, a charged colorant and a pH adjuster. The hydrogel-forming composition includes at least one charged species.

Abstract: Methods, processes and compositions are provided for a visual or chemochromic hydrogen-detector with variable or tunable reversible color change. The working temperature range for the hydrogen detector is from minus 100° C. to plus 500° C. A hydrogen-sensitive pigment, including, but not limited to, oxides, hydroxides and polyoxo-compounds of tungsten, molybdenum, vanadium, chromium and combinations thereof, is combined with nano-sized metal activator particles and preferably, coated on a porous or woven substrate. In the presence of hydrogen, the composition rapidly changes its color from white or light-gray or light-tan to dark gray, navy-blue or black depending on the exposure time and hydrogen concentration in the medium. After hydrogen exposure ceases, the original color of the hydrogen-sensitive pigment is restored, and the visual hydrogen detector can be used repeatedly.

Abstract: A corrosion detection product is a coating including a film forming material and a complexing agent, the complexing agent forming a complex when it comes into contact with a corrosion byproduct produced by corrosion of a substrate on which the coating is applied, the complex being detectably different from the complexing agent when the coating is exposed to radiation in order to detect the corrosion, the complexing agent being immobilized in the coating to reduce leaching of the complexing agent or the complex from the coating.

Abstract: The present invention relates to an assay device capable of testing for multiple analytes such as drugs using individual test strips for each analyte.

Abstract: An apparatus and method for analyzing characteristics of particles in a fluid stream. The particles may be intermittently illuminated at an interrogation location with a pulsed laser. A time-varying signal produced in response to the illumination may be analyzed as a function of a timing signal in order to determine characteristics of the particles in the fluid stream.

Abstract: Methods and kits to detect and quantitate NOx compounds in a biological sample are provided. The methods include reacting a mixture that includes a nitrite compound and a chromogenic reagent to form a colored compound, contacting the mixture with a retention medium configured to retain the colored compound, and detecting the colored compound retained on the retention medium.

Abstract: Methods for the preparation of cell compositions based on fluorescence following excitation at wavelength of or about 488 nm and isolated cell compositions obtained therefrom wherein isolated cells exhibit (i) autofluorescence at or about 520 nm or (ii) absence of fluorescence at or about 520 nm and a positive shift in the fluorescence detected at >630 nm. These methods provide for enrichment of immature or stem cancer-initiating cells from tumors (notably, cancers of the central and peripheral nervous system and metastasis to the brain) and methods for screening antitumor agents using the same. Also provided are methods of detecting immature or stem cancer-initiating cells in a cell sample and methods of detecting recurrence of cancer stem cells in a cancer stem cell sample following treatment with an agent.

Abstract: Method of determining a total HF concentration metric in an environment including measuring an uncorrected HF concentration metric in the environment based on a first infrared absorption measurement at a wavelength corresponding to a vibrational frequency of a non-hydrogen bonded gas phase HF molecule; determining an ambient H2O concentration metric in the environment available for reaction with the non-hydrogen bonded gas phase HF molecules at or about the time of obtaining the first infrared absorption measurement; calculating a HF hydrate concentration metric in the environment based on the uncorrected HF concentration metric, the ambient H2O concentration metric and a reaction equilibrium relationship between the non-hydrogen bonded gas phase HF molecule and the HF hydrate; and determining the total HF concentration metric in the environment based on the uncorrected HF concentration metric and an amount of HF determined by the HF hydrate concentration metric.

Abstract: When FRET efficiency is measured quantitatively by removing uncertain elements of fluorescence detection information, calibration information prestored in a storage means while including at least the leak rate of donor fluorescence component emitted from a donor molecule, the leak rate of acceptor fluorescence component emitted from an acceptor molecule, and the non-FRET fluorescence lifetime of the donor fluorescence component when FRET is not generated out of the fluorescence of a measurement object sample is acquired. The FRET fluorescence lifetime of the donor fluorescence component is then determined using the intensity information and phase information of fluorescence of the measurement object sample, the leak rate of donor fluorescence component and the leak rate of acceptor fluorescence component, thus determining the FRET fluorescence efficiency.

Abstract: A method for determining a shape correction value F for a laboratory liquid-analysis cuvette comprising a cuvette body with a circular cross-section for a photometric liquid analysis includes optically measuring an inside diameter d1 or an outside diameter d0 of the cuvette body to obtain a measured cuvette body diameter d1;d0. A shape correction value F is calculated from the measured cuvette body diameter d1;d0. The shape correction value F for the cuvette body is stored.

Abstract: The invention is directed towards methods and compositions for identifying the presence of surfactants in water. The invention is quite superior over the prior art because it can form a colorful complex in half the time, avoid the need for difficult separation steps, use a safer solvent and avoid the formation of messy foam. The invention involves adding to the water a cobalt thiocyanate reagent, pre-prepared from a cobalt salt and a thiocyanate salt, which forms a colorful complex with the surfactant. Chloroform is then added to the water. The cobalt reagent causes the virtually all of the surfactant to form a colored complex which rapidly migrates into the chloroform and prevents the surfactant from foaming. Once in the chloroform, a UV-vis spectrometer can easily and precisely identify the type and amount of surfactant that was in the water.

Abstract: The present invention relates to the use of a container, made of an inorganic additive containing plastic material, for reducing physical/chemical interaction between the container and an oil, fat and/or wax containing formulation contained therein.

Abstract: The invention relates to an assay to test for pyrethroids in a sample. The assay is particularly useful for testing material treated with pyrethroids, such as bed netting and the like.

Abstract: A micro vial assembly for performing microwave-assisted chemical reactions on small reaction mixture volumes is disclosed, wherein a reaction vessel (10) is sealed through a diaphragm (30) that is capped over an open end of the reaction vessel. The reaction vessel mouths in an end plane of a sleeve (20) surrounding the reaction vessel, the diaphragm being clamped for sealing the open end of the vessel by means of a cap (40) which is secured to the sleeve. The sleeve provides a radial extension of the reaction vessel in order to bridge the radial distance between a wall of the reaction vessel and other components in a system for performing microwave-assisted chemical reactions.

Abstract: Methods for determining the concentration of nitrates in several types of water samples by photochemical reduction without the use of toxic materials such as cadmium or hydrazine, and having an approximately 100% reduction efficiency are described. A water sample mixed with a buffered aqueous solution including ammonium salts and EDTA is irradiated using ultraviolet light having wavelengths effective for photochemical conversion of nitrate and nitrite ions (NOx) to detectable species. The resulting species may be quantitatively determined by diazotization using sulfanilamide followed by coupling with N-(1-napthyl)ethylenediamine dihydrochloride which produces a water-soluble azo dye having a magenta color which may be colorimetrically measured at 540 nm from which the nitrate and nitrite concentration in the sample is determined.

Abstract: Methods, devices, and kits are provided herein for the accurate and rapid detection of disease causing microbes in a sample by the detection of microbial components of which correlate to the presence of the microbe. Kits include a first binding agent operatively coupled to an immobilized support; and a second binding agent operatively coupled to one or more pH indicating moieties wherein the first and second binding agents bind with sufficient specificity to the microbial component to permit detection of that component which correlates to the presence of the microbe in the sample.

Abstract: A droplet interference system for sorting cells and a method for the same. The droplet interference system including a droplet generating system for producing a droplet which hits a fluid stream causing a selected segment of the fluid stream, and the cells contained therein, to be separated from the fluid stream.

Abstract: A material for use in vacuum bagging a component. The material includes a compound sensitive to moisture, such that an exposure of the compound to moisture or wetting causes a physical and/or chemical change in the compound that is visually detectable in the cover material. A method of leak detection during vacuum bagging involves the steps of: arranging a component in a vacuum bagging assembly, such as to form a fibre-reinforced plastic component; arranging a material according to the invention in the vacuum bagging assembly such that the compound sensitive to wetting or moisture is under, or on an inner side of, a sealing film or vacuum bag of the assembly; applying a vacuum to the vacuum bagging assembly to evacuate a space containing the component and sealed by the sealing film or vacuum bag; and wetting an outer surface of the sealing film or vacuum bag.

Abstract: Embodiments of the invention provide lateral flow and flow-through bioassay devices based on patterned porous media, methods of making same, and methods of using same. Under one aspect, an assay device includes a porous, hydrophilic medium; a fluid impervious barrier comprising polymerized photoresist, the barrier substantially permeating the thickness of the porous, hydrophilic medium and defining a boundary of an assay region within the porous, hydrophilic medium; and an assay reagent in the assay region.

Abstract: The present invention provide reagents and methods of using the reagents, for example, on automated staining devices, that facilitate detection of two or more antigens in a sample simply and efficiently.

Abstract: The present invention relates to a method for the determination of polysorbate in a protein-containing sample. The method of the present invention involves the pretreatment of the sample by alkaline hydrolysis followed by colorimetric determination.

Abstract: A Raman scattering probe, and a method of making such a probe, uses a capsule of nanometric size, such as a nanotube, to which is coupled at least one Raman-active molecule. The Raman-active molecule may be encapsulated in, or attached on the exterior of the capsule, and exhibits a Raman scattering response when the probe is illuminated by an excitation light beam. A functionalization chemical group that is attached to an exterior of the capsule provides a connection between the capsule and a target material. This functionalization may include a generic chemical functionalization that bonds with any of a plurality of secondary chemical groups each of which bonds directly with a different target. A method of using the probe for Raman spectroscopy or Raman imaging is also provided.

Abstract: The present invention relates to carboxamide-substituted dyes, the production and use of such dyes as labeling groups in analytics.

Abstract: The present disclosure generally relates to a dye that signals when the concentration of a quaternary ammonium compound in antimicrobial solution changes. A sensor is used to monitor changes in the dye wavelength as an indicator of the quat concentration. The use of a sensor leads to improved precision in measuring quat concentration by eliminating or reducing operator bias in reading color or wavelength changes. The dye can be incorporated into a variety of articles including towels, labels, containers, buckets, trays, sinks, spray bottles, liners for containers, buckets, sinks, or spray bottles, indictor wands or strips, and test kits.

Abstract: A device is provided for holding a sample for optical examination. The device comprises a body that defines a plurality of spots or wells. One or more non-specific interacting surfaces in the spots or wells are capable of non-specific binding of a said sample, a luminophore label, or their combination. A light conducting layer comprises material that is essentially non-transparent to optical excitation radiation and essentially transparent to optical luminescent radiation. A light input window couples luminescent light into said light conducting layer, and a light output window couples light out from said light conducting layer.

Abstract: An optoelectronic swept-frequency semiconductor laser coupled to a microfabricated optical biomolecular sensor with integrated resonator and waveguide and methods related thereto are described. Biomolecular sensors with optical resonator microfabricated with integrated waveguide operation can be in a microfluidic flow cell.

Abstract: A biochip for diagnostic purposes comprises a sample carrier made of a solid matrix, on the surface of said sample carrier is bound the sample material to be analysed which originates from a biological organism.

Abstract: An apparatus for performing surface enhanced Raman spectroscopy includes an optical waveguide, a plurality of flexible nano-structures, wherein the plurality of nano-structures have respective free ends positioned within an evanescent field to be generated by light propagated through the optical waveguide, wherein the plurality of nano-structures are movable from a first position and a second position, wherein in the first position, the free ends of the plurality of nano-structures are substantially spaced from each other and in the second position, the free ends of a plurality of the nano-structures are substantially in contact with each other.

Abstract: A surrogate addition device is described that adds a surrogate compound at a uniform transport rate to a flowing sample stream. The surrogate addition device includes a surrogate reservoir, a flow chamber, and a diffusion barrier. The surrogate reservoir can be configured to contain a surrogate solution where the surrogate solution includes a surrogate compound. The flow chamber includes an inlet port and an outlet port. At least a portion of the diffusion barrier is disposed in between the surrogate reservoir and the flow chamber. The diffusion barrier may include an inner surface that forms a wall of the surrogate reservoir, and an outer surface that forms a wall of the flow chamber. The flow chamber can be configured to receive a flowing sample solution across the outer surface of the diffusion barrier and also to diffuse the surrogate compound from the surrogate reservoir to the flow chamber.

Abstract: A rapid diagnostic device, assay and multifunctional buffer reagent are provided for the detection of a target analyte in a fluid test sample. The 2-step assay utilizes a dual component flow-through device comprising a test unit and a dried indicator reagent delivery unit for receiving the fluid sample and multifunctional buffer, respectively. The test unit comprises a reaction zone containing immobilized capture reagent that can bind to the target analyte, an absorbent zone supporting the reaction zone, and optionally, a blood separation zone in lateral fluid communication with the reaction zone. The delivery unit comprises a label zone permeated with a dried indicator reagent which can be placed in transient fluid communication with the reaction zone of the test unit during the assay procedure. The rapid diagnostic assay system reduces the number of assay reagents, method steps and time required for performance compared to other conventional assays.

Abstract: In an analysis device and a method for testing the catalytic activity of surfaces, a reaction cell is provided that has a recess for a sample that is provided with the catalytic surface. In the analysis device, an optical test of the reaction occurring in the reaction cell may occur. The reaction cell has a closed channel that is part of a fluid circuit. The reaction cell may be advantageously designed in a very space-saving manner in its scale, such that a portable use of the analysis cell is possible as well. Here, a simple measurement process of the absorption capacity of the sample fluid located in the reaction cell is conducted. To this end, a laser diode is provided, the measurement stream of which is directed into the reaction cell and reflected multiple times. The light intensity is measured by means of a photodetector.

Abstract: Methods, systems, and computer readable media for using actuated surface-attached posts for assessing biofluid rheology are disclosed. According to one aspect, a method for testing properties of a biofluid specimen includes placing the specimen onto a micropost array having a plurality of microposts extending outwards from a substrate, wherein each micropost includes a proximal end attached to the substrate and a distal end opposite the proximal end, and generating an actuation force in proximity to the micropost array to actuate the microposts, thereby compelling at least some of the microposts to exhibit motion. The method further includes measuring the motion of at least one of the microposts in response to the actuation force and determining a property of the specimen based on the measured motion of the at least one micropost.

Abstract: Methods and compositions are provided for detecting biomolecular interactions. The use of labels is not required and the methods can be performed in a high-throughput manner. The invention also provides optical devices useful as narrow band filters.

Abstract: Systems and methods for controlling fluids in microfluidic systems are generally described. In some embodiments, control of fluids involves the use of feedback from one or more processes or events taking place in the microfluidic system. For instance, a detector may detect one or more fluids at a measurement zone of a microfluidic system and one or more signals, or a pattern of signals, may be generated corresponding to the fluid(s). In some cases, the signal or pattern of signals may correspond to an intensity, a duration, a position in time relative to a second position in time or relative to another process, and/or an average time period between events. Using this data, a control system may determine whether to modulate subsequent fluid flow in the microfluidic system. In some embodiments, these and other methods can be used to conduct quality control to determine abnormalities in operation of the microfluidic system.

Abstract: Thus, the present invention provides a method for producing a biosensor comprising a substrate coated with a hydrophilic polymer, which comprises allowing a compound generating a reactive group as a result of external stimulus to bind to the surface of a substrate, and then giving external stimulus in a state where a hydrophilic polymer capable of forming a covalent bond with said reactive group is allowed to come into contact with the substrate, so that said hydrophilic polymer is allowed to bind to the substrate surface via a covalent bond with said reactive group.

Abstract: The present invention relates to a method for detecting an analyte in a sample comprising the steps of providing detection probes being labeled with a first reporter, which detection probes are capable of binding to the analyte, providing a solid support, providing capture probes being bound or capable of binding to the solid support, which capture probes are capable of binding to the analyte, thus concentrating the analyte on the solid support, contacting the sample with the detection probes, the solid support and the capture probes, and detecting the detection probes, wherein the detection of detection probes is conducted in the presence of quenching probes binding to surplus detection probes not being bound to the analyte and thereby quenching at least partially an emission of the first reporter of said surplus detection probes and/or the solid support is labeled with a second reporter different from the first reporter, imaging the sample at an emission wavelength of the second reporter, generating a m

Abstract: A method for surface modification of single walled carbon nanotubes is described. In one embodiment, the method includes the steps of providing a detergent solution, adding a plurality of single walled carbon nanotubes into the detergent solution, performing a first sonication to disperse the single walled carbon nanotubes in the detergent solution, and performing a second sonication after the first sonication to make detergent encased single walled carbon nanotubes. At least one of the plurality of single walled carbon nanotubes is at least partially wrapped by one or more detergent molecules to make it a detergent encased single walled carbon nanotube. In one embodiment, the detergent comprises SDS, PSS or a combination of them. The surface modified carbon nanotubes can be used to detect a chemical compound by associating a solution of the surface modified nanotubes with the chemical compound and optically detecting a chemical property change of the solution.

Abstract: A sensor for measuring an oxygen content in a liquid or gaseous sample has first and second sensor sections (14a, 14b). The first sensor section (14a) can be brought into contact with the sample and has a luminescent indicator dye embedded in an oxygen-permeable first polymer matrix. The second sensor section (14b) is arranged adjacent to the first sensor section (14a) and includes the same dye embedded in an oxygen-impermeable second polymer matrix. A light guide (10) guides luminescence excitation light from a light source (31, 32) to the sensor sections (14a, 14b) and guides luminescence emission light from the sensor section (14a, 14b) to a detector (39).

Abstract: An optochemical sensing device has source that emits radiation of a first and a second predetermined intensity, a detector, and a sensitive element that comprises a signal substance. To measure an analyte in a measurement medium, the sensitive element is contacted with the analyte. A first raw signal, which is dependent on the analyte content is obtained by exciting the signal substance with radiation of the first predetermined intensity. At a later time, a second raw signal is also obtained. A comparison of the raw signals yields a comparison value, which is compared against a predetermined limit value. If the comparison value exceeds the limit value, the radiation source is set at the first intensity. If the comparison value is smaller than the limit value, the radiation source is set at the lower second intensity. Using the lower radiation intensity prolongs the life of the sensitive element.

Abstract: The present invention generally provides methods and systems for performing in vivo flow cytometry by using blood vessels as flow chambers through which flowing cells can be monitored in a live subject in vivo without the need for withdrawing a blood sample. In some embodiments, one or more blood vessels are illuminated with radiation so as to cause a multi-photon excitation of an exogenous fluorophore that was previously introduced into the subject to label one or more cell types of interest. In some other embodiments, rather than utilizing an exogenous fluorophore, endogenous (intrinsic) cellular fluorescence can be employed for in vivo flow cytometry. The emission of fluorescence radiation from such fluorophores in response to the excitation can be detected and analyzed to obtain information regarding a cell type of interest.