Abstract: A method and a device for the analysis of 5-hydroxyindoles or catecholamines with high sensitivity. New chemiluminescence labeling agents, 6-aminomethylphthalhydrazide or 1,2-bis(phthalhydrazino)ethylenediamine, are reacted with 5-hydroxyindoles or catecholamines to form their stable derivatives. The derivatives emit strong luminescence in the presence of an oxidizing agent. In the chemiluminescence detection method, there is extremely low background noise and thus the method enables analysis with high sensitivity.

Abstract: This invention relates to a lytic reagent and a method of using the lytic reagent for automatically determining leukocyte subpopulations in blood. More specifically, the new lytic reagent lyses red blood cells and affects the eosinophils which enables the differentiation of at least one subpopulation of leukocytes. The lytic reagent is an acidic, hypertonic aqueous solution containing alkali metal salt of alkyl sulfite, an eosinolytic agent, a nonionic surfactant and a physiological salt. When used in combination with a second lytic reagent system, one is able to obtain at least a five part differential of leukocytes using DC and RF measurements.

Abstract: Methods and compositions are provided for improved kinetics of light production from luciferase activity in beetle luciferase-luciferin reactions utilizing a luciferase inhibitor. Thus, the invention provides methods and compositions for assaying samples for the presence of a beetle luciferase in conjunction with a luciferase inhibitor.

Abstract: Quantitative buffy coat (QBC) analysis control compositions are provided which sufficiently mimic whole blood and perform consistently in various QBC systems. The control compositions contain a red blood cell component composed of non-human mammalian red blood cells and a granulocyte component composed of fixed human granulocytes. Methods of making and using the control compositions are also provided.

Abstract: A method of staining cellular material where a sample containing the cellular material is stained with a stain solution containing a cyanine dye excitable by infrared rays to contrast its nuclear material from its cytoplasmic material.

Abstract: The invention relates to improvements in determining the fertilizing capacity of a human semen sample using a reagent solution which contains 0.1-5% by weight K.sub.2 PO.sub.4 H/KPO.sub.4 H.sub.2 to adjust the pH of the solution to 6.5-8.0. After treatment with the reagent solution, the result is considered positive when the diameter of the halo is equal to or larger than 7.5.mu. in 10-25% of the spermatozoa read, as long as the membrane of the head of the spermatozoon is intact. Kits suitable for performance of the claimed method are also described.

Abstract: A lytic reagent composition is provided which selectively stromatolyses red blood cells in a blood sample. In addition, a lytic reagent system is provided which enables the differentiation of at least three subpopulations of leukocytes. A method for using the lytic reagent system is also provided. Still further, the lytic reagent system finds use in the determination of the hemoglobin in the blood. The lytic reagent system utilizes an alkyl sulfate, polyoxyethylene based surfactant and acid with a hypertonic, alkaline, stabilizing reagent. The system and analysis method maintains the cellular morphology of the leukocytes and can be used to analyze normal and abnormal blood samples, fresh and aged blood, human and non-human animal blood samples.

Abstract: The present invention relates to a process for indicating the presence of organic vapors comprising the steps of determining the color, absorption or emission spectra of a Pt--Pt double-complex salt of platinum or a neutral platinum complex in the absence of organic vapor, exposing said double-complex salt of platinum or a neutral platinum complex to a gaseous environment, determining the color, absorption or emission spectra of said double-complex salt of platinum or a neutral platinum complex after exposure to said gaseous environment, and comparing the color, absorption and/or emission spectra of said double-complex salt of platinum or a neutral platinum complex in the absence of organic vapor with the color, absorption and/or emission spectra of said double-complex salt of platinum or a neutral platinum complex after exposure to said gaseous environment to determine if there is a difference in the color, absorption and/or emission spectra.

Abstract: A method for determining a component of interest in a fluid, the method comprising four steps. The first step is to suspend a droplet or a film of a liquid. The second step involves contacting the fluid with the droplet or film. The third step involves diffusing at least a portion of the component of interest into the droplet or film to form an analyte. The fourth step involves determining the component of interest by analyzing the analyte. The fluid can be either a liquid or a gas. The analyte can be analyzed while in the form of a suspended droplet or film.

Abstract: A cyanide-free lytic reagent composition and method for measuring the total hemoglobin concentration in a blood sample, for counting the number of leukocytes and for deferential counting of three leukocyte subpopulations including lymphocytes, monocytes, and granulocytes are described. The cyanide-free lytic reagent composition includes a hemolytic surfactant chosen from quaternary ammonium salts, pyridinium salts, organic phosphate esters, and alkyl sulfonates to lyse erythrocytes and release hemoglobin, and an organic ligand chosen from triazole and its derivatives, tetrazole and its derivatives, alkaline metal salts of oxonic acid, melamine, aniline-2-sulfonic acid, quinaldic acid, 2-amino-1,3,4-thiadiazole, triazine and its derivatives, urazole, DL-pipecolinic acid. isonicotinamide, anthranilonitrile, 6-aza-2-thiothymine, adenine, 3-(2-thienyl)acrylic acid, benzoic acid and alkali metal and ammonium salts of benzoic acid, and pyrazine and its derivatives to form a stable chromogen with hemoglobin.

Abstract: In order to determine iron in serum by releasing the bound iron through addition of a protein denaturing agent, reduction of the released iron to Fe.sup.2+, addition of a color reagent solution and photometric measurement of the color complex that forms, a mixture of a denaturing agent containing urea or a urea derivative and a fatty alcohol polyglycol ether are added to the sample solution.

Abstract: The present invention relates to reagents and processes for the preparation of diagnostics which use a chromogenic redox detection system and whose chromogenic redox detection system essentially remains unaffected by interference from reducing. compounds in the sample material.

Abstract: Diaza-18-crown-6 compounds of the formula I: ##STR1## wherein X is a phenol, naphthol or quinolinol moiety selected from those of the formulae: ##STR2## R.sub.1, R.sub.2, R.sub.3, R.sub.4 and R.sub.5 are independently selected from hydrogen, halo, cyano, nitro, (C.sub.1 -C.sub.6) alkyl, (C.sub.2 -C.sub.8) acyl, acetamido, mercapto, alkyl or arylsulfonyl, trifluoromethyl, aryl, and substituted aryl wherein the aryl moiety is selected from phenyl and naphthyl and the aryl substituent is selected from halo, cyano, nitro, (C.sub.1 -C.sub.6) alkyl, (C.sub.2 -C.sub.8) acyl, phenyl, acetamido, mercapto, alkyl or arylsulfonyl and trifluoromethyl; provided that when R.sub.1, R.sub.2, R.sub.3 and R.sub.5 are hydrogen and X is phenol, R.sub.4 is not nitro; and provided that when X is phenol and R.sub.5 is hydrogen, R.sub.1 (or R.sub.2) and R.sub.4 are not both nitro.

Abstract: Provided are a method of determining the amount of cholesterol in high-density lipoprotein (HDL), which comprises measuring the amount of cholesterol in low-density lipoprotein (LDL), very-low-density lipoprotein (VLDL) and chylomicron (CM) in a sample in the presence of a sugar compound and/or a protein solubilizing agent, and calculating the difference between the amount of cholesterol in LDL, VLDL and CM and the total amount of cholesterol in the sample, and a method of determining the amount of cholesterol in HDL, which comprises measuring the amount of cholesterol in HDL in a sample in the presence of a sugar compound and/or a protein solubilizing agent.

Abstract: Whole blood is mixed with a reticulocyte reagent system that has a reticulocyte staining reagent and a diluent reagent, used in combination. This mixture is incubated at room temperature for between about 15 minutes to about 4 hours. The incubated mixture is then analyzed and the light scattering properties of the cells are detected, collected, differentiated and quantitized. Data gathering includes, at least, 10 and 90 degree light scatter detection.

Abstract: A carbon monoxide (CO) detection system is connected into an anesthesia gas delivery system. The system comprises, among other things, a CO sensor unit containing an inexpensive, replaceable sensor that detects the presence of CO in anesthesia, an in-line adapter that exposes the detection unit to the main stream of the gas and can be placed in a variety of different locations along the gas stream and a side-stream adapter for the removal and analysis of gas stream samples using a CO sensor unit outside of the main gas stream. There is also apparatus capable of measuring the response of the sensors to CO exposure, and data acquisition and a data processing unit for storing, processing and displaying the CO sensor response data. In a preferred embodiment there is a carbon monoxide detection system comprising a detection unit including a sensor unit and a measurement unit. The sensor unit detects carbon monoxide based on the change or rate of change of the optical characteristics of the sensor unit.

Abstract: The invention relates to a disposable electronic diagnostic instrument designed for use in an Over-the-Counter (OTC) cholesterol test kit for measuring cholesterol levels of blood. The instrument is designed and calibrated specifically for use with diagnostic test strips supplied with the OTC cholesterol test kit.

Abstract: A process and apparatus for preparing blood for analysis of white blood cells involves:preparing a mixture made up of blood and a lysing agent,emitting luminous radiation in the direction of the mixture,receiving the light emitted through the mixture,comparing the quantity of light received at a pre-determined threshold, the process of erythrolysis, being complete when the quantity of light corresponds to the threshold and,neutralizing the action of the lysing agent when erythrolysis is completed by the addition of an appropriate reagent.

Abstract: A colorimetric assay of enaldehydes or of malonic dialdehyde as lipid peroxidation indices in an aqueous medium includinga) addition to the medium of a reagent of a compound of general formula I and their optional addition salts with organic or inorganic bases or with organic or inorganic acids. ##STR1## in which formula: A and C, which may be identical or different, each represent H, ##STR2## wherein A and C cannot simultaneously represent H, with:R.sup.1 =H; alkyl; aralkyl; aryl substituted on the aryl ring; alkyl sulfonate Y.sup.+ ; alkyl phosphonate, Y.sup.+ ; or alkyl carboxylate, Y.sup.+ ;R.sup.2 =H; --OR.sup.4 ; F; Cl; Br; I; --NO.sub.2 ; SO.sub.3.sup.31 Y.sup.+ ; --CN; --COOR.sup.4 ; or --CONR.sup.5 R.sup.6 ;R.sup.3 =H; --OR.sup.4 ; --NR.sup.5 R.sup.6 ; --SR.sup.4 ; F; Cl; Br; I; --NO.sub.2 ; --SO.sub.3 --Y.sup.+ ; --CN; --COR.sup.5 ; --COOR.sup.4 ; or --CONR.sup.5 R.sup.6 ;R.sup.4 =H; alkyl; aralkyl; or aryl substituted on the aryl ring;R.sup.

Abstract: A method and apparatus for the detection of hydrazine, monomethylhydrazine, 1,1-dimethylhydrazine in air (or other gas medium) or in an aqueous solution. The detection is accomplished by introducing a stream of air, or other gas medium, or aqueous solution suspected of containing hydrazine, monomethylhydrazine, 1,1-dimethylhydrazine or mixtures thereof into a pH controlled reagent solution containing an aromatic dicarboxaldehyde to react with the hydrazine, monomethylhydrazine, 1,1-dimethylhydrazine or mixtures thereof, respectively, and by exposing the reacted reagent solution to an excitation wavelength range and monitoring an emission from the exposed reagent solution at an emission wavelength range to detect the presence of a hydrazine derivative, monomethylhydrazine derivative, 1,1-dimethylhydrazine derivative, or mixtures thereof (i.e.

Abstract: The present invention provides an optical fluorescence based sensor for measuring the concentration of a gas (e.g., CO.sub.2 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: The present invention is a method for the detection of hydrogen peroxide in biological fluids or an aqueous solution which involves contacting the solution with an oxidation-reduction indicator and a transition metal complex. The transition metal complex is either a creatinine coordinated with iron or a guanidine coordinated with iron.

Abstract: The invention relates to a reagents kit for the quantitative analysis of proteins or/and peptides, comprising a reagent A containing 0.7 to 2 mmol/l Cu.sup.2+ ions and 2 to 4 mmol/l tartrate in alkaline solution and a reagent B containing 1 to 1.5 mmol/l ascorbic acid and 0.5 to 0.8 mmol/l bathocuproine, with the proportion by volume of reagent A to reagent B being 1:8 to 1:12 and the joint volume of reagent A and reagent B being between 750 .mu.l and 3000 .mu.l.

Abstract: A method for the rapid quantitation of minute amounts of particulate insoluble substantially opaque colored light absorptive substances is disclosed. The method may be employed to quantitate such particulates which are formed as an end product of an assay productive thereof. The method is practiced by bringing into contact particles to be quantified and an optical component or matrix formed of substantially water insoluble reflective granules of material which is substantially nonabsorptive of light and has a light scattering coefficient of at least about eighty. The opacity of the particles to be quantitated, when in contact with the component granules, masks and prevents any substantial light flow through the contacted granule surface areas which, with the absorptivity of light by the contacting particles, is effective rapidly and dramatically to reduce the light transmittance capability of the optical component.

Abstract: A method of pretreating aqueous chemical oxygen demand (COD) samples to remove the risk of potential chloride ion interference. The method comprises acidifying an aqueous COD test sample, and thereafter passing the acidified sample through a source of pentavalent bismuth (Bi.sup.5+) such as sodium bismuthate.

Abstract: A method for classifying and counting leukocytes which includes the steps of (i) adding a first reagent used for classifying leukocytes into four groups which contains, (a) at least one ionic surfactant in a sufficient amount to lyse erythrocytes and to damage a part of cell membrane of leukocytes, (b) at least one organic compound having an anionic group in a sufficient amount to bond with a cationic component present in leukocytes to give morphological differences between leukocytes, (c) a nonionic surfactant, and (d) a buffer for adjusting pH, to a part of a blood sample to determine information on the cell size and morphological features in order to classify leukocytes into four groups consisting of three groups corresponding to lymphocytes, mononuclear cells and eosinophils and one group corresponding to neutrophils and basophils; (ii) adding a second reagent used for measuring basophils to another part of the blood sample to determine information on at least the cell size in order to classify basophils,

Abstract: A method is disclosed for identifying the source of a transported chemical shipment. The method employs either a chemical element or an organic compound with one or more atoms that are non-radioactive isotopes generally not found in nature. A small quantity of the isotopic compound is introduced into the storage vessel containing the chemical to be transported prior to shipment of the chemical. Upon arrival at its destination point, a sample of the chemical shipment is analyzed. Matching the isotopic compound found in the chemical with the isotopic compound introduced into the storage vessel prior to shipment is indicative that the shipped chemical is identical to the chemical received. Non-radioactive materials may further be employed for detecting the source of a newly introduced contaminant in a water supply. The chemical substance may be a non-radioactive isotope of the chemical shipment being transported.

Abstract: A series of organic test papers are described for the detection and identification of all types of organic compounds such as aldehydes, ketones, esters, acids, amines, isocyanates, anhydrides, amides, nitrides, aromatics, phenols, ethers, and other organic compounds, said test papers comprising an absorbent paper or microporous plastic impregnated with a reagent or reagents capable of reacting with a class of organic compounds. The method of using the test papers for the identification of organic compounds comprises making a presumptive identification of the class of the unknown sample using FTIR spectroscopy, and then placing this presumptively identified sample onto the paper to generate a new substance known as a derivative of the organic compound, which aids in the identification of the unknown organic compound.

Abstract: A process and test kit for the rapid qualitative determination of fat oxidation based on an iodometric method for peroxide value and employing ready-made test solutions is disclosed. A visible color change is used to determine whether a fat sample contains an amount of fat peroxides in excess of a predetermined amount, and is therefore unacceptable.

Abstract: Methods and compositions are provided for improved kinetics of light production from luciferase activity in beetle luciferase-luciferin reactions. Thus, the invention provides methods, compositions and test kits for assaying samples for the presence of a beetle luciferase or, using a beetle luciferase-luciferin reaction, the presence of ATP. The invention also provides the complex of the coenzyme, Coenzyme A, a beetle luciferase and oxyluciferin in its exited state in the luciferase-luciferin reaction and luciferyl-CoA, the thioester of Coenzyme A and luciferin (D-(-)-2-(6'-hydroxy-2'-benzothiazolyl)-.DELTA..sup.2 -thiazoline-4-carboxylic acid).

Abstract: A multipurpose reagent system for rapid analysis of a whole blood sample allowing the determination of at least five classes of peripheral white blood cells, nucleated red blood cells, and lymphocyte immunophenotyping on automated hematology instrumentation. The multipurpose reagent system lyses red cells rapidly, while it concurrently fixes white cells and preserves surface antigens on lymphocytes. The multipurpose reagent system comprises from about 3 to 7 grams per liter of a non-quaternary ammonium salt, from about 0.04 to about 0.10 percent by volume of an aliphatic aldehyde with one to four carbons, from about 10 mM to about 20 mM of a non-phosphate buffer which is inert to the aliphatic aldehyde, and a sufficient amount of water to give a pH between 5.5 and 7.5 and an osmolality of between about 160 to about 310 mOsm per liter.

Abstract: Methods and compositions are provided for improved kinetics of light production from luciferase activity in beetle luciferase-luciferin reactions. Thus, the invention provides methods, compositions and test kits for assaying samples for the presence of a beetle luciferase or, using a beetle luciferase-luciferin reaction, the presence of ATP. The invention also provides the complex of the coenzyme, Coenzyme A, a beetle luciferase and oxyluciferin in its exited state in the luciferase-luciferin reaction and luciferyl-CoA, the thioester of Coenzyme A and luciferin (D-(-)-2-(6'-hydroxy -2'-benzothiazolyl)-.DELTA..sup.2 -thiazoline-4-carboxylic acid).

Abstract: A tetraethyl orthosilicate-based, sol-gel glass composition with additives selected for various applications. The composition is made by mixing ethanol, water, and tetraethyl orthosilicate, adjusting the pH into the acid range, and aging the mixture at room temperature. The additives, such as an optical indicator, filler, or catalyst, are then added to the mixture to form the composition which can be applied to a substrate before curing. If the additive is an indicator, the light-absorbing characteristics of which vary upon contact with a particular analyte, the indicator can be applied to a lens, optical fiber, reagant strip, or flow cell for use in chemical analysis. Alternatively, an additive such as alumina particles is blended into the mixture to form a filler composition for patching cracks in metal, glass, or ceramic piping.

Abstract: Improved assay methods utilizing stable, enzymatically triggered chemiluminescent 1,2-dioxetanes with improved water solubility are provided. Assays are performed by a capsule chemistry analytical assay method wherein fluid capsules comprising discrete aqueous segments containing either a chemiluminescent dioxetane reagent or an activating agent separated by an oil-based isolating fluid are flowed through a conduit, and subsequently reacted to produce light.The improvement comprises using a dioxetane substituted with two or more water-solubilizing groups disposed on the dioxetane structure to provide the chemiluminescence. Compositions comprising such a dioxetane, a non-polymeric surfactant enhancer and optionally a fluorescer, provide enhanced chemiluminescence and eliminate the problem of reagent carryover when used in assays performed on capsule chemistry analytical systems.

Abstract: An apparatus and method is presented for the determination of water soluble glycols and polyglycols (polyalkoxylates). The apparatus and method are particularly suited for the on-site quantitation of glycols and polyglycols in aqueous drilling fluids.

Abstract: A continuous flow analyzing method and an apparatus for carrying out the analyzing method wherein a sample is injected in a continuously flowing carrier and the sample is introduced into a detector by the carrier to thereby perform a quantitative analysis contained in the sample. In the method the sample to be analyzed is filled into a sample introduction switchover valve (SISV); a portion of the sample from the SISV is injected into the carrier and an analysis of this sample is conducted to obtain a detection peak for the analyzed sample. These steps are repeated and the sample is continuously analyzed by, in the case where a detection peak obtained in the detector is under an optimum analysis range, increasing an injection amount of the sample, and in the case where the detection peak obtained in the detector is over the optimum range, decreasing the injection amount of the sample. Adjustment of the detection peak is repeated until the detection peak reaches the optimum analysis range.

Abstract: The present invention provides a method of increasing the duration of detectable photon emission of a luciferase-luciferin reaction. The method provides a luciferase-luciferin reaction in which photon emission can be detected for up to and including eight hours. A method of the present invention can also be used to detect the presence of luciferase in biological samples. The present invention also provides a composition used in detecting the presence of luciferase in biological samples.

Abstract: The present invention describes the use of a variety of merocyanine dyes and substituted merocyanine dyes for detecting and quantifying poly(amino acids), including peptides, polypeptides and proteins. The labeled proteins or peptides are highly colored, but are also detected by their strong fluorescence enhancement. Poly(amino acids) are detected in solution, in electrophoretic gels, and on solid supports, including blots and dipsticks. The present method of staining is highly sensitive, extremely facile, and relatively non-selective.

Abstract: A cyanide-free method and reagent for determining the concentration of total hemoglobin in a whole blood sample accurately in less than 10 seconds comprising a ligand selected from the group consisting of imidiazole, imidazole derivatives, N-hydroxyacetamide, N-hydroxyl amine, pyridine, oxazole, thiazole, pyrazole, pyrimidine, purine, quinoline, and isoquinoline, and a surfactant with strong erythrolytic capability selected from the group consisting of lauryl dimethylamine oxide and octylphenoxy polyethoxyethanol. The reagent pH is adjusted to about 11 to about 14. Rapid mixing of the reagent with a blood sample leads to the formation of a stable chromogen whose absorbance can be measured between 540 and 550 nm. The cyanide-free reagent is ideal for use on an automated high through-put clinical hematology analyzer.

Abstract: The invention features a medium for the detection of target microbes in a liquified environmental or biological sample in less than 18 hours.

Abstract: A self-addressable, self-assembling microelectronic device is designed and fabricated to actively carry out and control multi-step and multiplex molecular biological reactions in microscopic formats. These reactions include nucleic acid hybridization, antibody/antigen reaction, diagnostics, and biopolymer synthesis. The device can be fabricated using both microlithographic and micromachining techniques. The device can electronically control the transport and attachment of specific binding entities to specific micro-locations. The specific binding entities include molecular biological molecules such as nucleic acids and polypeptides. The device can subsequently control the transport and reaction of analytes or reactants at the addressed specific microlocations. The device is able to concentrate analytes and reactants, remove non-specifically bound molecules, provide stringency control for DNA hybridization reactions, and improve the detection of analytes. The device can be electronically replicated.

Abstract: A method and analyzer for monitoring the progress of a chemical process in which a fixed volume sample of the reactive mixture of the chemical process is periodically gathered and injected into a fluid stream of a liquid carrier. The sample in the liquid carrier is passed through an infrared detector which detects the amount present in the sample of a species of the reaction mixture which is indicative of the progress of the chemical process.

Abstract: The invention concerns the use of test strips with a flat, preferably oblong foil which carries a matrix containing a photoactive chromogenic substance to pre-determine the duration of stay in the sun that is possible without sunburn, a test system for this determination containing test strips and a test strip pack, a test strip pack and a method for the pre-determination of the maximum possible duration of stay in the sun without sunburn using the test system.

Abstract: The present invention provides various methods for detecting errors in a blood analysis system. The system includes a blood analyzer and a molded plastic rotor with a series of chambers and capillary channels through which blood is processed and distributed to cuvettes which contain lyophilized reagents. The rotor is placed in the analyzer which spins the rotor, and an optical system reads the cuvettes as light is flashed through the cuvettes.

Abstract: Disclosed are devices for amplifying a preselected polynucleotide in a sample by conducting a polynucleotide amplification reaction. The devices are provided with a substrate microfabricated to include a polynucleotide amplification reaction chamber, having at least one cross-sectional dimension of about 0.1 to 1000 .mu.m. The device also includes at least one port in fluid communication with the reaction chamber, for introducing a sample to the chamber, for venting the chamber when necessary, and, optionally, for removing products or waste material from the device. The reaction chamber may be provided with reagents required for amplification of a preselected polynucleotide. The device also may include means for thermally regulating the contents of the reaction chamber, to amplify a preselected polynucleotide. Preferably, the reaction chamber is fabricated with a high surface to volume ratio, to facilitate thermal regulation.

Abstract: A universal standard chemical reagent for quantitative visual and spectrometric analysis of compounds having reactive functional groups, including mixtures and homologs of said compounds, said reagent comprising a compound of the general formula Q-B-f, wherein: Q stands for an organic moiety which can be measured quantitatively, visually by color, spectroscopically, or fluorometrically; B represents a non-reactive organic bridging unit linking the moiety Q to a reactive functional group f, said bridging unit being of sufficient length or size to prevent any possible interaction of Q that might alter its spectroscopic properties even upon derivatization; and f is a reactive group which can react with a compound to form covalently bonded derivatives.

Abstract: The present invention provides an improved method of detecting or transferring a biological material whereby a biological material is adhered to a membrane which is then contacted with a detecting reagent, wherein the improvement comprises utilizing a polyvinylidene fluoride membrane which has been subjected to a temperature of at least about 80.degree. C. but less than the temperature at which the membrane softens and deforms for a time sufficient to reduce the ability of the detecting reagent to directly adhere to the membrane.

Abstract: A composition for determining pH of a solution comprises a fluorescent carbazine dye covalently bound to a solid support. A method of determining pH of a solution comprises placing the composition in the solution, contacting the composition with a selected wavelength of light to excite fluorescence by the carbazine dye, measuring intensities of the fluorescence at two selected wavelengths, calculating a ratio of fluorescence intensities at the two selected wavelengths, and correlating the ratio with a predetermined relationship of such ratios to pH. A fiber optic system for measuring pH of a solution with the carbazine-dye-containing composition is also disclosed.

Abstract: A system for determining the concentration of fructosamine in sera which consists of a first reagent in which a tetrazolium salt which reduces all reactive substances in sera including fructosamine and a second reagent which is responsive to all reactive substance in sera other than fructosamine. The difference in color change as between the two allows the determination of concentration of fructosamine.

Abstract: A method of analyzing aqueous samples for Chemical Oxygen Demand (COD) which involves using an analysis reagent comprised of a mixture of stabilized Manganese III ion and an inorganic non-oxidizing acid such as sulfuric or phosphoric acid. Manganese III ion (or manganosulfuric acid complex) is purple, and, as it is reduced to Manganese II ion, the purple color decreases to colorless. Manganese III Chemical Oxygen Demand test is preferred over the presently available chromium reagent test because Chromium VI ion is a known carcinogen, the reagent is photosensitive and a silver catalyst is required. Manganese III is not carcinogenic or photosensitive and does not require a silver catalyst.