Abstract: The present invention includes the characterization of the major salivary protein or enzyme of the corn earworm Helicoverpa zea for triggering resistance to bacterial blight and frogeye leafspot in soybeans and for triggering resistance to insects in tomatoes. The invention includes an enzyme or a novel protein secreted from the salivary glands of certain insects including the saliva of species belonging to the order Hymenoptera and Lepidoptera. The regurgitant of Helocoverpa zea obtained from the functional salivary glands contains a protein that possesses glucose oxidase activity. The amino acid sequence of the protein is unique and when the protein is applied to plants, it triggers disease and insect resistance systematically. The physical and kinetic attributes of the enzyme are a pH of 7.0, a pI of 4.4 and a molecular weight of 88 kd. The km and Vmax of the enzyme for glucose is 26.9 mmol and 26.7 &mgr;mol min−1 mg−1, respectively.

Abstract: Methods and apparatus for automated sample analysis are provided in which a plurality actuators are involved in moving a samples from one compartment to another, and appropriate reactants are combined with the sample in one or more of the compartments. The actuators are preferably contained in a device that also has a detector, data reduction capabilities, and a printer. Contemplated signal detectors include a photomultiplier tube, a photodiode, and a charge-coupled device. Steps contemplated to be performed automatically include aliquoting the sample, diluting the sample, contacting at least a portion of the sample with a reagent having a substantially selective binding towards the analyte. Contemplated reactants include sense and antisense nucleic acids, antibodies and antigens, solid-phases such as paramagnetic beads, reagents, other substrates, and wash solutions.

Abstract: Sensitive methods for identifying compounds having biological activity comprising combining living cells with two fluorescent membrane permeable ionic dyes having the same charge sign, the first of which has an emission spectrum which overlaps the excitation spectrum of the second fluorescent membrane penetrative dye. The fluorescence is then induced by illuminating the dyes at a wavelength corresponding to the excitation spectrum of the first fluorescent dye and emission is then registered at a wavelength corresponding to the emission spectrum of the second fluorescent dye (FRET). The change in the FRET is indicative of a modulation of cell membrane potential by the biologically active compounds.

Abstract: Homogeneous fluorescence polarization (anisotropy) assays for detecting and quantifying metal ions in solution, based the metal-dependent binding of a fluorescent ligand to an unlabeled macromolecule, or the binding of a metal ion to a fluorescent labeled macromolecule. The metal-dependent binding of a fluorescent ligand to an unlabeled macromolecule (metallo-macromolecule) effects a measurable change in anisotropy as will the binding of metal ions to a fluorescent labeled macromolecule. Binding of the fluorescent ligand to the unlabeled macromolecule is metal dependent with the change in anisotropy being proportional to the concentration of bound metal ions. No binding of the fluorescent ligand to the macromolecule occurs in the absence of metal ions. Conversely, if the fluorescent label is first conjugated to a metallo-macromolecule and the metallo-macromolecule is subsequently stripped of its metal ion, it may then be used to transduce the binding of metal ions.

Abstract: The present invention relates to a method for detection of protein using a counter-dye composition, on polyaciylamide gels, and the counter-dye composition for detection of protein on polyacrylamide gels. More specifically, the present invention relates to a method for detection of protein in a high sensitivity on polyacrylamide gels in a rapid and simple manner, comprising the step of staining the polyacrylamide gels with a counter-dye composition containing an acidic organic dye and a basic organic dye, and the counter-dye composition for detection of protein on polyacrylamide gels.

Abstract: Method and reagent for the determination of iron in a biological sample in which the bound iron is released, the released iron is reduced to Fe2+, a color reagent solution is added and the color complex that is formed is measured photometrically, characterized in that a water-soluble EDTA-complexing compound in particular an indium and/or scandium salt is added to the sample.

Abstract: A composition suitable for use in an ECL assay and kits therefor wherein electromagnetic radiation emitted by said composition is detected, which composition comprises (a) a metal-containing ECL moiety which, when oxidized by exposure to an effective amount of electrochemical energy, is capable of being converted to an excited state from which electromagnetic radiation is emitted upon exposure of the excited ECL moiety to conditions sufficient to induce said emission; (b) an amine or amine moiety which, when oxidized by exposure to an effective amount of electrochemical energy, forms a strong reducing agent in said composition; and (c) an electrolyte capable of functioning as a medium in which said ECL moiety and said amine or amine moiety can be oxidized by exposure to electrochemical energy.

Abstract: The present invention relates to a composition for use in fluorometry, a method of fluorometry and the use of a class of new reagents in fluorometry. The composition comprises a substrate which is a non-fluorescent derivative of a fluorophore, and a shifting reagent which shifts the absorbance wavelength maximum of the fluorophore which maximum is naturally above 450 nm. The shifting reagent is present in an amount predetermined to shift the maximum to a preset value.

Abstract: A rapid fluorescence staining method for facilitating flow cytometry analysis of reticulocytes is described. The method comprises contacting cells with a cocktail containing a detergent, sphering agent, and a cell impermeable dye, such as TO-PRO-3, for about one minute. Advantageously, the inventors have found that the cocktail permits the dye to penetrate the cell membrane rapidly.

Abstract: A non-immunochemical method is disclosed for determining homocysteine in a sample. A combination of the sample and a first compound that comprises a cis-1,4-dioxo-2-butene moiety or hydrolytically derived precursor thereto is provided in a liquid medium. The combination is subjected to conditions under which homocysteine reacts with the cis-1,4-dioxo-2-butene moiety or hydrolytically derived precursor thereto to form a product, which is then detected without separation of the product from the medium. A second compound such as a mercaptan containing reagent or an antibody for cysteine can optionally be included to facilitate discrimination of the product formed from homocysteine from products formed from other amines in the sample. The product from the reaction of homocysteine has a six-member ring fused to an unsaturated five-member ring. The junction of the rings is comprised of the nitrogen of homocysteine and an atom that comprises a double bond.

Abstract: The object of the present invention is to measure a concentration of protein stably at a temperature not higher than 25° C., which is a possible ambient temperature at home, and further to expand the measurable concentration range while preventing an obstruction due to a suspending particle such as a bubble and the like, using a reagent prepared by mixing an acid in a solution containing tannin, tannic acid and m-galloyl gallic acid. By mixing the reagent in a solution to be detected to opacify the solution, intensities of at least a transmitted light or a scattered light of the solution to be detected is measured, and a protein concentration thereof is determined based on the intensity. The present invention also provides a method for measuring a concentration of a solution and a method of urinalysis, wherein a protein concentration is measured after measuring an angle of rotation.

Abstract: A magnetic focusing immunosensor for the detection of pathogens comprising a laser, an exciting fiber and a collecting fiber, a fiber optic magnetic probe in communication with the collecting and exciting fibers and means for detecting, collecting and measuring fluorescent signals in communication with the collecting fiber. The probe and the collecting and exciting fibers are configured to focus paramagnetic microspheres attached to antigen/antibody/optically labeled complexes in a predetermined pattern in the field of view of the collecting fiber while blocking background interference.

Abstract: The present invention provides dried chemical compositions comprising dried beads. Typically, the beads comprise reagents suitable for analysis of biological samples, in particular analysis of blood samples in centrifugal analyzers.

Abstract: Polymers having amine-thiol terminal moieties are provided. The amine-thiol terminal moieties are imparted by using amine-thiols as chain transfer agents in aqueous addition polymerizations. The polymers are useful as mineral dispersants, as water-treatment additives for boiler waters, cooling towers, reverse osmosis applications, sugar refining, paper production, geothermal processes and oil wells, and as detergent additives acting as builders, anti-filming agents, dispersants, sequestering agents and encrustation inhibitors.

Abstract: A method and apparatus for the manipulation of colloidal particles and biomolecules at the interface between an insulating electrode such as silicon oxide and an electrolyte solution. Light-controlled electrokinetic assembly of particles near surfaces relies on the combination of three functional elements: the AC electric field-induced assembly of planar aggregates; the patterning of the electrolyte/silicon oxide/silicon interface to exert spatial control over the assembly process; and the real-time control of the assembly process via external illumination. The present invention provides a set of fundamental operations enabling interactive control over the creation and placement of planar arrays of several types of particles and biomolecules and the manipulation of array shape and size. The present invention enables sample preparation and handling for diagnostic assays and biochemical analysis in an array format, and the functional integration of these operations.

Abstract: Sensing the presence of furfuraldehyde (FFA) in oil is effected by a porous solid sensor (10) comprising aniline acetate entrapped in an inert matrix. The matrix may be a sol-gel preferably based on methyltrimethoxysilane. The solid sensor (10) reacts with FFA to form a pink colored complex which has a characteristic which correlates with the concentration of FFA in the oil and which can be measured photo-optically. Photo-optical measurement may be by absorption or fluorescence when the sensor is irradiated with an interrogating beam. The absorption maximum wavelength is about 525 nm and irradiation at that wavelength produces a maximum fluorescent output at about 570 nm.

Abstract: The invention relates to a bicarbonate-containing medical solution package. The package comprises a gas-permeable plastic container holding a bicarbonate-containing medical solution and a gas-impermeable plastic packaging member containing the gas-permeable plastic container. A carbon-dioxide atmosphere is established in the space between the container and packaging member. In addition, a pH indicating device is contained within the space between the container and packaging member. The pH indicating device is a gas-permeable plastic packet containing a bicarbonate-containing fluid (similar to the medical solution) and a pH indicator. The pH indicator undergoes a change in color in response to a change in pH of the fluid. Use of this package allows the easy monitoring of a change in pH and consequent aging of the medical solution due to prolonged storage or damage to the outer packaging member.

Abstract: The present invention relates to a method for detection of DNA using a counter-dye composition containing two dyes of which electric charges are contrary to each other, on polymer gels, and the counter-dye composition for detection of DNA on polymer gels. More specifically, the present invention relates to a method for detection of DNA in a high sensitivity on polymer gels in a rapid, simple and safe manner, comprising the steps of staining the polymer gels with a counter-dye composition containing a cationic dye and an anionic dye and then macroscopically observing the gel without radiation of ultraviolet ray, and the counter-dye composition for detection of DNA on polymer gels.

Abstract: A process is described for applying spatially defined reagent areas to a solid phase which is characterized in that a liquid containing an adsorptive binding reagent is contacted with spatially defined areas of a solid phase which comprises an essentially continuous metal or metal oxide surface for an adequate time period to enable the formation of adsorptive bonds between the binding reagent and the solid phase.

Abstract: Hematology control compositions and systems used to measure a plurality of parameters in a blood sample are provided. The hematology control compositions are particularly useful as a control for multi-parameter, automated instrument systems. The control compositions comprise a reticulocyte component, a white blood cell component, a red blood cell component, a nucleated red blood cell component, a platelet component and a reticulated platelet component. Methods of making and using the control compositions are also provided.

Abstract: The present invention provides an optical fluorescence based sensor for measuring the concentration of a gas (e.g., CO2 or ammonia) in a medium such as blood which has superior dry web sensor performance, enhanced sensor consistency for transparent sensor calibration, improved autoclave stability and rapid rehydration of the sensor. In a preferred embodiment, the sensors of the present invention comprise microcompartments of an aqueous phase having a pH sensitive indicator component and a nonionic amphipathic surfactant within a hydrophobic barrier phase comprising a plurality of dispersed hydrophobic particles.

Abstract: A method and apparatus detect exposure to an oxidation-type sterilant using a non-PH-sensitive bleachable dye as a chemical indicator. A change in color indicates exposure to oxidation-type sterilant.

Abstract: A method for measuring the concentration of an anionically charged polymer in an aqueous solution is described and claimed. The method requires a reagent solution that is also described and claimed. The reagent solution comprises water, Nile Blue Dye and chelant, with the chelant being selected from the group consisting of the alkali metal or ammonium salts of phosphonobutane tricarboxylic acid. The method involves using absorbance measurements to determine the amount of anionically charged polymer present in an aqueous sample. The method is very rapid and thus is very useful under field conditions.

Abstract: This invention relates to lytic reagents and methods of using the lytic reagents for automatically determining leukocyte subpopulations in blood. More specifically, the new lytic reagents selectively lyse red blood cells and certain leukocyte subpopulations, which enables the differentiation of at least one subpopulation of leukocytes. The lytic reagents contain an ethoxylated long chain amine, a quaternary ammonium salt and an acid. When used in combination with a second lytic reagent system, one is able to obtain at least a five part differential of leukocytes by impedance and light scatter measurements, by impedance and radio frequency measurements, or by radio frequency and light scatter measurements.

Abstract: In accordance with the present invention, a method of conducting an assay of a sample containing an analyte of interest includes the step of forming a mixture so as to bring a metal-ligand complex into interactive proximity with the sample containing the analyte of interest. The mixture is irradiated with electromagnetic light energy so as to cause emission of light indicative of the analyte of interest. The emitted light is measured, and the measurement of the emitted light is utilized to measure the analyte of interest. The metal-ligand complex can be [Re(bcp)(CO)3(4-COOHPy)]+, [Os(phen)2(aphen)]2+, [Os(tpy)(triphos)]2+, [Os(tppz)2]2+, and [Os(ttpy)2]2+, or the like. Also, the present invention is directed to a metal-ligand complex of the formula [Re(bcp)(CO)3(4-COOHPy)]+.

Abstract: Disclosed is an improved method for the detection of creatinine in a fluid test sample by contacting the test sample with cupric ions, a hydroperoxide, citrate and an oxidizable dye which gives a colored response in the presence of oxygen free radicals and a pseudoperoxide. The improvement involves stabilizing the reagent formulation by the addition thereto of an ionizable phosphate containing compound such as phytic acid.

Abstract: This invention relates to lytic reagents and methods of using the lytic reagents for automatically determining leukocyte subpopulations in blood. More specifically, the new lytic reagents selectively lyse red blood cells and certain leukocyte subpopulations, which enables the differentiation of at least one subpopulation of leukocytes. The lytic reagents contain a polyoxyethylene based surfactant, a quatemary ammonium salt and an acid. When used in combination with a second lytic reagent system, one is able to obtain at least a five part differential of leukocytes by impedance and light scatter measurements, by impedance and radio frequency measurements, or by radio frequency and light scatter measurements.

Abstract: Methods and devices are provided for controlling a fluid flow over a sensing surface within a flow cell. The methods employ laminar flow techniques to position a fluid flow over one or more discrete sensing areas on the sensing surface of the flow cell. Such methods permit selective sensitization of the discrete sensing areas, and provide selective contact of the discrete sensing areas with a sample fluid flow. Immobilization of a ligand upon the discrete sensing area, followed by selective contact with an analyte contained within the sample fluid flow, allows analysis by a wide variety of techniques. Sensitized sensing surfaces, and sensor devices and systems are also provided.

Abstract: Blood samples are stabilized for methemoglobin determination with a buffer composition containing (a) carbon monoxide-containing water; (b) sodium tetraborate or potassium tetraborate; and (c) KCN or NaCN. The buffer composition preferably may also have an erythrocytolysis agent. The buffer fixes the valence state of heme iron at a concentration representative of the blood at the time of collection, and maintains that fixed state for an extended period of time preventing further methemoglobin formation. The buffer also prevents reduction of existing target analyte, i.e., methemoglobin (ferric hemoglobin, Fe3+ hemoglobin) to normal reduced hemoglobin (ferrous hemoglobin, Fe2+ hemoglobin).

Abstract: An analysis element for analyzing a specific component in a liquid sample is disclosed, which comprises a reagent comprising insoluble particles and boric acid. Furthermore, a method for preparing a reagent liquid for use in the preparation of an analysis element for analyzing a specific component in a liquid sample is disclosed, which comprises adding insoluble particles and boric acid to the reagent liquid.

Abstract: The present invention provides a device and a process for detecting an analyte in a biological fluid. The device comprises a separating matrix for separating analyte from the fluid and means for detecting the analyte, where the separating matrix contains HEPES buffer, preferably in an amount between 70 and 150 millimolar. The process comprises applying the sample to the device having a separating matrix and then detecting analyte in the sample using the detection means. The presence of HEPES in the separation layer shortened the detection time.

Abstract: A harness indicator is highly reactive to a trace amount of Ca2+, and is slow to degrade in a high temperature environment of greater than 50° C. In one embodiment, the hardness indicator contains EBT, a pH buffer, and a masking agent as main components, and an admixture of Mg-EDTA. In another embodiment, the hardness indicator contains EBT, a pH buffer, and a masking agent as main components, and an admixture of anhydrous Mg-EDTA. In another embodiment, the hardness indicator contains EBT, a pH buffer, and a masking agent as main components, and an admixture of anhydrous Mg-EDTA and potassium sorbate. In a further embodiment, the hardness indicator contains EBT, a pH buffer, and a masking agent as main components, and an admixture of Mg-EDTA and potassium sorbate. In a further embodiment, the hardness indicator contains EBT, a pH buffer, and a masking agent as main components, and an admixture of potassium sorbate.

Abstract: A method for detecting neoplasia or cancer of the colon or rectum comprising obtaining a sample of colorectal mucus from the rectum of a patient, and detecting the presence of a marker selected from the group consisting of long chain aliphatic aldehydes containing 12-20 carbon atoms, particularly CH3(CH2)14CHO and CH3(CH2)16CHO; and plasmalogen-bound precursors thereof. Preferably the method comprises treating the sample with Schiff's Reagent and detecting neoplasia or cancer of the colon or rectum based upon the coloration produced at about 560-590 nm in the sample by the treatment. The method does not require the step of adding an enzyme for detecting the disaccharide marker &bgr;-D-Gal(1-3)-D-GalNAc(&agr;1-Thr/Ser) and a saccharide marker containing D-galactose and/or 2-acetamido-2-deoxy-D-galactose.

Abstract: Hematology reference control cells and method of manufacture. The invention relates to the methods of preparing stable white blood cell (“WBC”) and nucleated red blood cell (“NRBC”) fractions and the hematology control reagents containing such stablized cells for primary use on a multi-angle light scatter based hematology instrument.

Abstract: An improved test is described for chlorine in pool and spa water where potassium monopersulfate is used as an oxidizing agent and DPD is used as an indicator. N,N-bis(hydroxyethyl)-2-aminoethane sulfonic acid or bicine is used to mask or eliminate the potassium monopersulfate so that it does not interfere with the DPD indicator. The test is very reliable and accurate.

Abstract: Urine is tested for presence of malondialdehyde by mixing it with a reagent consisting of about 90-110 parts 20% acetic acid, about 13.5-16.5 parts Ingredient A, and about 4.5-5.5 parts Ingredient B, wherein Ingredient A is comprised of sodium metabisulfite, phosphoric acid and deionized water in the proportions of about 18-22 grams sodium metabisulfite, 9-11 ml of concentrated phosphoric acid, and about 450-550 ml deionized water, and Ingredient B is comprised of basic fuchsin and Ingredient A in the proportion of about 0.45-0.55 grams basic fuchsin to about 90-110 ml Ingredient A. A color change is observed when malondialdehyde is present in the urine in a concentration greater than about 2 ppm.

Abstract: A urine pH indicator has a plurality of hydrophilic, non-ionic, polymer foam carrier particles. The carrier particles are impregnated with an indicator complex having more than one chromophore and indicating more than one pH threshold via at least three distinguishable colors. The carrier particles are preferable chopped and soaked in a solution containing the chromophore complex. Upon evaporation of the solvent, the chromophore complex is bound to the carrier particles which can then be spread upon animal litter to receive urine and indicate pH via color display.

Abstract: A method for the labeling of molecules through the reaction of molecules to be labeled with labels at a solid phase (matrix), characterized in that the molecules enter a reaction chamber in which a matrix loaded with a reactive component is provided, and after the coupling has taken place, the labeled molecules leave the reaction chamber through a porous means.

Abstract: In a method of determining heparin content, a known amount of thrombin (FIIa) or activated coagulation factor X (FXa) is added to a mixture which comprises a known concentration of chromogenic substrate (S), a known concentration of antithrombin (AT) and a sample having an unknown heparin concentration. The amount of FIIa or FXa is chosen such that at most 20%, of the S present is reacted during the period which the AT needs to deactivate all the FIIa or FXa present. The final concentration of the reacted chromogenic substrate p-nitroanilide ([pNA].sub.final) is determined after completion of the reactions, and the [pNA].sub.final is used to determine the rate constant (k.sub.dec) of the reaction of FIIa or FXa with AT using the relationship: ##EQU1## The heparin concentration in the sample can then be determined using the value of k.sub.dec from a predetermined calibration curve of k.sub.dec against heparin concentration.

Abstract: The concentration of formaldehyde in air is measured by the method of the invention. More specifically, the invention relates to a method for analyzing formaldehyde in air by collecting the air and implementing an analysis of the concentration of formaldehyde at the site where such air is found.

Abstract: The invention includes compositions comprising and methods of using 1,2-indanedione derivatives for detecting an amine compound such as an amino acid. Methods of detecting and recording the pattern of a fingerprint on a surface are also included, as are a kit for detecting an amine compound such as a constituent of a fingerprint. The invention further includes a device for developing a fingerprint and a method of making 1,2-indanedione derivatives.

Abstract: The present invention is directed to an improved analyte systems which are able to compensate for interfering signals and to provide accurate detection and/or quantification of analytes in a sample. In particular, the invention describes new methods, systems, and devices for indirectly determining the presence of one or more analytes in a multi-component medium.

Abstract: Tests for elevated pH and volatile amines in aqueous fluids are disclosed, including tests useful in the diagnosis of bacterial vaginosis and in other biological conditions. By using formulated indicators and indicators held in matrices that are permeable to gas but not to liquid, the tests provide clear and sharp transitions detectable by visual or machine-readable means rather than by subjective judgments such as small gradations in color or olfactory determinations. The tests lend themselves readily to iconic readouts of the test indications and to the inclusion of positive and negative controls.

Abstract: The invention provides a very fast and reliable method and reagent composition for determining reticulocyte and erythrocyte counts, identification and characterization, as well as platelet counts, in a whole blood sample using fully automated hematology analyzers. The reagent composition includes a zwitterionic surfactant as sphering agent for reticulocytes and erythrocytes, an organic cationic dye, e.g., Oxazine 750, for staining the reticulocytes, and buffer solution components for maintaining a reagent pH of about 7.2 to 7.8, and an osmolarity of about 292.+-.5. On the basis of the particular pH, ionic strength, and dye concentration, the reagent composition of the present method improves upon previous methods, thus allowing fully automated blood sample analyses to be completed in less than about 30 seconds, with only about a 20 second incubation of sample in the reagent solution before analysis.

Abstract: The invention relates to a method for determining the ionic strength and/or the specific weight of aqueous liquids and a reagent for this purpose, the composition of the reagent being such that the color change indicating the ionic strength is essentially directly dependent on the specific weight of the liquid to be determined and not on a pH shift.

Abstract: A uranium-containing/metal binding complex and process for the determinat of natural and depleted uranium in biological samples such as water, urine, blood serum, saliva, amniotic fluid, cerebrospinal fluid, sweat, stool extract, synovial fluid, tears, semen extract, sputum, and peritoneal fluid. The samples are mixed with a buffer, one or more masking agents, and a solubilizing compound, to form a uranium-containing metal binding complex composition, followed by the addition of a pyridylazo indicator dye to said composition. The increase in absorbance due to the uranium-dye complex is determined with a spectrophotometer or colorimeter.

Abstract: Tests for elevated pH and volatile amines in aqueous fluids are disclosed, including tests useful in the diagnosis of bacterial vaginosis and in other biological conditions. By using formulated indicators and indicators held in matrices that are permeable to gas but not to liquid, the tests provide clear and sharp transitions detectable by visual or machine-readable device rather than by subjective judgments such as small gradations in color or olfactory determinations. The tests lend themselves readily to iconic readouts of the test indications and to the inclusion of positive and negative controls.

Abstract: A method for identifying methyl methacrylate (MMA) in the liquid part of a liquid/powder system used to form artificial finger nails and toenails. The chemistry used to identify MMA in liquid monomers provides an accurate and inexpensive way to monitor the use of MMA in liquid monomers in violation of a ban of MMA by the Food and Drug Administration (FDA) for purposes of creating artificial finger nails and toenails.

Abstract: A method of testing a material without the use of animals to determine the potential of the material to harm human or animal cells due to contact includes forming a biomembrane having at least some constituent matter of human or animal tissue, applying a quantity of material to the membrane, maintaining the biomembrane and quantity of material in contact for a period of time, and monitoring the change in the physical properties of the biomembrane caused by the quantity of material.

Abstract: This invention provides a method for determining the concentration of a gas to be detected by a gas detector using a gas reactive pigment, wherein the dynamic range of the detectable concentration can be controlled. The method comprising bringing a gas to be detected such as a halogen gas, a hydrogen halide gas or the like into contact with a gas detector placed in a detection area and comprising a gas reactive pigment tetraphenylporphyrin or a derivative thereof represented by the general formula (1) or a metal complex of tetraphenylporphyrin or a derivative thereof represented by the general formula (2); and irradiating said gas detector with a detection beam and measuring a color change in said gas detector to determine the concentration of said gas to be detected, wherein the measurement is carried out in the temperature range from 40 to 80.degree. C. of said detection area; and a detection apparatus for carrying out the said method are disclosed.