Abstract: A liquid measuring device is described for carrying out the assay using a gas or vapor permeable but liquid impermeable membrane barrier to control the volume of liquid to be measured or transferred. The membrane may be used in any instance where a fixed volume of liquid needs to be measured.

Abstract: Methods and devices are described for rapidly and simultaneously detecting, quantifying, and imaging gases, odors, malodors, volatiles and semi-volatiles using gas chromatography coupled with arrays of organic conducting polymers. The methods utilize changes in the polymer conductivity as a function of temperature to detect volatile organic molecules upon adsorption to the polymers. By raising the sensor temperature, adsorbed materials are further desorbed. This eliminates the fundamental problems of sensor fouling resulting from exposure to sulfur, nitrogen or ketone containing malodors. In a second embodiment, the resulting gas effluents from the sensor array are mixed with air, oxygen or hydrogen to produce a cloud of luminance that is detected by a charge-coupled device.

Abstract: A new method is proposed where a limited amount of MBTH is used to detect a point of interest (POI) of an aldehyde in a test sample. Preferably, it reacts with aldehyde first to form an azine. Only if there is remaining MBTH, it is oxidized to another species which combines with the azine to form formazan. However, if there is enough aldehyde, all the MBTH is converted to azine and there is no formation of blue color. Thus, by using the limiting agent MBTH to test the amount of aldehyde around the point of interest, then less aldehyde would produce more blue color and more aldehyde would produce less blue color. This method is especially useful in the quality control of aldehyde products. The end color may be different depending upon the order of addition of the reactants. For example, if an oxidizing agent and MBTH are mixed before adding the aldehyde, a light green to green/blue color results. This method could be used for solution test or for tests on a solid phase such as on nylon membrane.

Abstract: The invention relates to a process for the diagnosis of illnesses, pathologic states as well as physiological measurement units, which is based on the immobilization of recognition structures by means of a specific linker at specific functional polymer surfaces.

Abstract: A sampling material for a carbonyl compound in a gas comprising a reagent capable of converting a carbonyl compound to a derivative thereof supported on a cation exchanger; and a sampling cartridge for a carbonyl compound in a gas wherein a sampling material for a carbonyl compound in a gas comprising a reagent capable of converting a carbonyl compound to a derivative thereof supported on a cation exchanger is packed in a column are provided. The sampling cartridge can be used for analyzing a carbonyl compound such as formaldehyde with ease and at a high sensitivity and high accuracy, and has excellent storage stability.

Abstract: A composition, method, and device for quantitatively determining the concentration of an aldehyde in a sample are disclosed. The device includes a test pad having a suitable carrier matrix incorporating an indicator reagent composition capable of interacting with the aldehyde to produce a detectable and measurable response for aldehyde concentration over a range of 0% to over 4%, by weight of the sample. An indicator reagent composition contains: (a) a protein, (b) an amine, (c) a color indicator, (d) preferably a neutral, nonionic polymer, such as a water-soluble cellulose polymer, and (e) a carrier. An indicator reagent composition is incorporated into a carrier matrix, like filter paper, to provide a test pad useful in a dry phase aldehyde assay of a sample, especially for samples containing a high concentration of glutaraldehyde or formaldehyde.

Abstract: The invention concerns a method for rapidly determining the presence of malondialdehyde (MDA) in urine, food products and cosmetic products. It simply consists in placing a drop of urine, fat or a cosmetic product on an indicator paper impregnated with an aqueous solution comprising thiobarbituric acid and glycolic acid. A red chromogen is obtained resulting from the combination of malondialdehyde with thiobarbituric acid, ill the form of a characteristic ring.

Abstract: A method is described for determining the presence of a volatile component in a test sample. The method involves use of two separate vessels, one of which is capable of being placed wholly within the other vessel. The test sample is placed in the larger vessel, and an indicator solution is placed in the smaller, inner vessel. Then a gas-tight closure is placed on the top of the outer, larger vessel. The assembly is heated to an elevated temperature, whereby the volatile target analyte which is released from the test sample transfers to the inner vessel and is absorbed by the indicator solution. The indicator solution can be analyzed by means of a calorimeter, spectrophotometer, etc.

Abstract: This invention provides a RP-HPLC method, for the determination of logPoct values, which combines ease of operation and high accuracy, and which has been shown to work for a set of 36 molecules largely comprised of drugs. The general features of the method are: i) compound sparing (≦1 mL of a 30-50 &mgr;g/mL solution needed), ii) rapid determinations (20 minutes on average), iii) low sensitivity to impurities, iv) wide lipophilicity range (6 logPoct units), v) good accuracy, vi) excellent reproducibility. A linear free energy relationship (LFER) analysis, based on solvation parameters, shows that the method encodes the same information obtained from a shake-flask logPoct determination. The value generated via this method is referred to as ElogPoct .

Abstract: Simple equations that relate glucose, glutamate, glucuronate, and phenylacetylglutamine 13C NMR multiplet areas to gluconeogenesis and pyruvate recycling during metabolism of [1,2,3-13C3]propionate are presented. This indicates that a direct measure of gluconeogenesis, pyruvate recycling, and anaplerosis may be obtained from a single 13C NMR spectrum of suitably prepared blood or urine samples collected after oral administration of enriched propionate, acetaminophen, and phenylacetate.

Abstract: The present invention provides methods for detecting the presence of an analyte indicative of various medical conditions, including halitosis, periodontal disease and other diseases are also disclosed.

Abstract: An improved biologic electrode array and methods for manufacturing and using the same. In one aspect, a matrix of electrodes each coupled to a respective sample-and-hold circuit is provided. The electrodes and sample-and-hold circuits are integral and form an array within a single semiconductor chip, such that each sample-and-hold circuit may be loaded with a predefined voltage provided by a single, time-shared digital-to-analog converter (DAC). Further, all of the sample-and-hold circuits may be accessed through a multiplexer which may be scanned through some or all of the electrode locations. Each sample-and-hold circuit may comprise a capacitor and one or more transistor switches, the switch(es), when closed, providing electrical communication between the capacitor and a source line formed in the matrix.

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: 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: A sterilization system using a sterilization process monitoring device which is capable of indicating the efficacy of the sterilization process in an enclosed sterilization container while still maintaining the sealed state of the sterilization container. The process monitoring device comprises at least one biological indicator and/or at least one chemical indicator. Upon completion of the sterilization cycle, the process monitoring device can be advantageously removed from the system to determine chemical and/or biological efficacy of the sterilization process. The removal of the biological and/or chemical indicators does not disturb the sterilized state of the articles inside the sterilization container.

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: 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: 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: A solid support template for solid phase synthesis of amino group containing compounds is provided that comprises amino-ketone core compounds of the general formula:A-L-NH(CR.sub.1 R.sub.2).sub.n COR.sub.3linked to appropriate insoluble substrates to create solid support templates having the general formula:Polymer-X-L-NH(CR.sub.1 R.sub.2).sub.n COR.sub.3where L is a multifunctional monomer carrying a first functional group that forms a covalent bond with X and a second functional group comprising an amine and L, R.sub.1, R.sub.2 and R.sub.3 are selected from the group consisting of alkyl, alkyl-aryl, alkenyl, alkenyl-aryl groups having up to 6 carbon atoms and substituted forms thereof. The amino-ketone templates are useful for the solid phase synthesis of compounds such as the imidazoles, benzodiazepines, pyrazines, and steroid mimics.

Abstract: Apparatus and method for determining at least one parameter, e. g., concentration, of at least one analyte, e. g., urea, of a biological sample, e.g, urine. A biological sample particularly suitable for the apparatus and method of this invention is urine. In general, spectroscopic measurements can be used to quantify the concentrations of one or more analytes in a biological sample. In order to obtain concentration values of certain analytes, such as hemoglobin and bilirubin, visible light absorption spectroscopy can be used. In order to obtain concentration values of other analytes, such as urea, creatinine, glucose, ketones, and protein, infrared light absorption spectroscopy can be used. The apparatus and method of this invention utilize one or more mathematical techniques to improve the accuracy of measurement of parameters of analytes in a biological sample.

Abstract: Sensors (20, 50, 70) for use in detecting the presence of sugars and other analytes (target molecules). The sensor is composed of a metal complex that binds to the target molecule and releases a proton or includes an exchangable ligand which is exchanged for the target molecule during the binding interaction between the metal complex and the target molecule. The result of the binding interaction is the release of a proton, hydroxide ion or ligand species generated during the ligand exchange. Measurement of the release of proton, hydroxide ion or other ligand species from the sensor (20, 50, 70) provides an indirect indication of target molecule concentration. The metal complexes may be attached to support structures (10, 12) to provide both anchoring and positioning of the metal ions to increase selectivity of sugar/metal complex interactions. Detection systems in which pH is used as an indication of proton or hydroxide release are disclosed, as are detection systems in which Cl.sup.- release is used.

Abstract: The selectivity of response of resistive gas sensors to specific gases or vapors is improved by the selection of specified gas-sensitive materials which are not previously known for the applications described, which include detection of hydrocarbons in the presence of CO, H.sub.2 S, SO.sub.2, chlorine, NO.sub.2, CO.sub.2 (especially in low concentrations), CFC's, ammonia, free oxygen by determination of partial pressures, and numerous organic gases and vapors.

Abstract: A kit for monitoring mammalian reproductive cycles by monitoring variations in the quantity of one or more low molecular weight volatile compound having a molecular weight of less than 50 grams per mole present in a body constituent sample is disclosed. Samples of a body constituent selected from the group consisting essentially of humoral fluid, breath and body cavity air are collected from a female mammal a multiple number of times during the reproductive cycle. The quantity of a low molecular weight volatile compound in each sample is measured. In the preferred embodiment, the low molecular weight volatile compound, acetaldehyde, will be measured and monitored. Variations in the quantity of the low molecular weight volatile compound appearing in each sample is monitored to determine the phase of the mammal's reproductive cycle and to predict the occurrence of ovulation.

Abstract: The present invention provides for a method and system for determining the concentration of a surfactant in a transparent hydrocarbon by performing the steps of adding a solid to the hydrocarbon; adding a second masking reagent to the hydrocarbon; mixing to form a dispersion; separating the dispersion from the mixture; and measuring the optical absorption of the dispersion.

Abstract: An improved biologic electrode array and methods for manufacturing and using the same. In one aspect, a matrix of electrodes each coupled to a respective sample-and-hold circuit is provided. The electrodes and sample-and-hold circuits are integral and form an array within a single semiconductor chip, such that each sample-and-hold circuit may be loaded with a predefined voltage provided by a single, timeshared digital-to-analog converter (DAC). Further, all of the sample-and-hold circuits may be accessed through a multiplexer which may be scanned through some or all of the electrode locations. Each sample-and-hold circuit may comprise a capacitor and one or more transistor switches, the switch(es), when closed, providing electrical communication between the capacitor and a source line formed in the matrix.

Abstract: The present invention relates to methods for detecting teratogen exposure in neonates. In particular, the present invention is directed to the detection of prenatal (i.e., in utero) exposure to ethanol. In accordance with the present invention, fatty acid ethyl esters, produced as the by-products of non-oxidative ethanol metabolism are detected in samples such as meconium and cord blood.

Abstract: Resistance of given plant tissue to an inhibitor of acetolactate synthase is identified by(a) combining in an aqueous medium a sample of the plant tissue, the inhibitor of acetolactate synthase, and an inhibitor of keto acid reductoisomerase;(b) allowing time for acetolactate to accumulate;(c) rupturing the cells;(d) acidifying the mixture to convert any accumulated acetolactate to acetoin; and(e) calorimetrically detecting the presence of acetoin in the mixture.

Abstract: A method for diagnosing premenstrual syndrome in a female human comprising the step of measuring the ratio of esterified L-carnitine to free L-carnitine in a patient's serun or plasma. Women who have an esterified to free L-carnitine ratio of greater than about 0.22 are diagnosed as having premenstrual syndrome.

Abstract: Reagent and method are offered for the screening of the functional condition of the body by the person's saliva. Reagent presents itself as an H2O solution, containing ions of Fe3+, chloride ions and multi-atom alcohol .n the concentrations 0.05-3.0M; 0.05-4.0M, and 0.1-5.0M accordingly. Screening is conducted by means of mixing of the persons saliva with the reagent in the following comparison of colour mix with control; during this an orange colour is correlated with the norm; yellow-diabetes SD-1, functional disorders of pancreas; bright-pink and red initial stages of hypertonic disease, diabetes SD-2, pathological influence of smoking; dark-red, developed forms of hypertension, diabetes SD-2, pathogenic-influence of smoking or other toxic substances, leading to the emphasized energetic disorder.

Abstract: Method and reagent composition for covalent attachment of target molecules, such as nucleic acids, onto the surface of a substrate. The reagent composition includes groups capable of attracting the target molecule as well as groups capable of covalently binding to the target molecule, once attracted. Optionally, the composition can contain photoreactive groups for use in attaching the reagent composition to the surface.

Abstract: The present invention relates to advanced glycosylation endproducts, and particularly to the use of novel cyclopentenone aminoreductones, 3-alkylamino-2 -hydroxy-4-hydroxymethyl-2-cyclopenten-1-ones. Such AGEs can be used in various diagnostic and therapeutic methods.

Abstract: Aliquot of a urine sample is placed in a first automated analyzer sampling cup and a known standard is placed in a second cup. The urine sample and standard are transferred to separate cuvettes and at least one reagent composition in an aqueous medium is injected into the cuvette. The reagent composition contains a compound to remove substances in the urine interfering with a calorimetric reaction, a compound to convert B-hydroxybutyric acid in the urine to acetoacetic acid in the presence of nicotinamide adenine dinucleotide and reading at a specified wavelength to determine quantitatively the total ketone bodies in the patient's urine.

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 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 for monitoring mammalian reproductive cycles by monitoring variations in the quantity of one or more low molecular weight volatile compound having a molecular weight of less than 50 grams per mole present in a body constituent sample is disclosed. Samples of a body constituent selected from the group of humoral fluid, breath and body cavity air are collected from a female mammal a multiple number of times during the reproductive cycle. The quantity of a low molecular weight volatile compound in each sample is measured. In the preferred embodiment, the low molecular weight volatile compound, acetaldehyde, will be measured and monitored. Variations in the quantity of the low molecular weight volatile compound appearing in each sample is monitored to determine the phase of the mammal's reproductive cycle and to predict the occurrence of ovulation.

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: 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: Diacetyl, especially resulting from spoilage of chilled red meat, is monitored by exposing an aromatic ortho-diamine at acidic pH to an environment containing, or possibly containing, diacetyl and detecting any change in absorption or reflection of electromagnetic radiation due to the ortho-diamine.

Abstract: Disclosed is a method of determining whether a solvent contains a tautomeric cyclic 1,2-dione. It is first determined whether the pH of the solvent is acidic (<5), basic (>9), or neutral (5 to 9). If the pH is neutral, an acid or a base is added to make the pH acidic or basic, respectively. The UV absorbance at a first wavelength between about 230 nm and about 270 nm and at a second wavelength between about 280 and about 320 nm is determined. If the pH is acid, it is changed to basic and, if it is basic, it is changed to acidic. The UV absorbance at the first and second wavelengths is again determined. The presence of a tautomeric cyclic 1,2-dione is indicated if the absorbance at the first wavelength was greater when the solvent was acidic and the absorbance at the second wavelength was greater when the solvent was basic. The concentration of the tautomeric cyclic 1,2-dione can be determined by multiplying the change in absorbance by a constant.

Abstract: This invention relates to power transformers. More particularly, this invention pertains to a method and apparatus for detecting the degree of degradation of paper insulation in a transformer by determining the concentration of furaldehyde in the transformer oil. A reagent for detecting the presence of furaldehyde in transformer oil comprising: (a) a primary amine selected from the group consisting of aniline, toluidine, anisidine, aminophenol or an amine; (b) a second component having about 3 mL of about 15 to 33 (weight to volume) percent of acetic acid alone, or in combination with citric acid; from about 67 to 85 (volume) percent of a halogenated hydrocarbon selected from the group consisting of dichloromethane, chloroform, carbontetrachloride, dichloroethane, trichloroethane, tetrachloroethane, trichloroethylene, tetrachloroethylene; about 4 (weight to volume) percent of salicylic acid; and about 1 (weight to volume) percent of an anti-oxidant; and (c) a third component having about 1.

Abstract: Electrospray ionization mass spectroscopy (ESI-MS) methods, tagging reagents and novel compounds for labeling neutral compounds to provide ionized compounds for mass spectroscopy analysis, and novel compounds discovered using such EES-MS methods, including fulleroids

Abstract: The present invention is directed to derivatives of aroyl-2-quinoline-carboxaldehyde and their use in detection and quantification of minute amounts of primary amines.

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: For determining 3-deoxyglucosone derivatives which are intermediate metabolites of the Maillard reaction in body fluids such as blood, urine, serum, plasma and the like in gas chromatography/mass spectrometry, .sup.13 C-labelled compounds or .sup.14 C-labelled compounds are useful as an internal standard substance. More specifically, 3-deoxyglucosone derivatives having the formula (I): ##STR1## wherein *C is .sup.13 C or .sup.14 C, X is O or N--OR wherein R is Me, Et or H, and Y is SiMe.sub.3 or SiMe.sub.2 tBu, and their production are provided. The measurement of 3-deoxyglucosone derivatives is useful in diagnosing diseases such as diabetes and diseases complicated with diabetes, including diabetic nephrosis, various renal disorders, renal insufficiency, metabolic diseases of carbohydrate and the like.

Abstract: A method of analysing a sample for alkyl ketene dimer (AKD) comprises treating the sample (or extract thereof) with a reagent which will react with an AKD to produce a detectable derivative. The preferred reagent is 4-(N,N'-dimethylamino)pyridine.

Abstract: Biological preparations or specimens are treated for a subsequent microscopic inspection. For this purpose it is necessary that the inner structure that is to be studied does not change prior to and during inspection. It is thus necessary to subject the specimens to a chemical and/or mechanical pretreatment for increasing the permeability of the specimen surface to a fixation substance in the form of an aqueous solution that contains an aldehyde fixation agent, preferably a highly volatile fixation agent or substance. The exposure of the specimens to the fixation substance takes place by immersion and/or spraying and/or fumigation. The fixation agent is preferably volatile and in the form of an aldehyde proportion of about 5% by volume or of an acrolein proportion of about 10% by volume.

Abstract: The molecular weight distribution of carboxymethylcellulose or its salt is determined by gel permeation chromatography using a metal-amine complex and/or a metal-alkali complex as the mobile phase solvent. The column geometry (inside diameter/length) and flow rate for this determination are 1:40-100 and 0.2-0.5 ml/min., respectively. According to this method, the GPC determination of molecular weight distribution can be performed under the same conditions for both starting pulp and CMC.

Abstract: A method for analyzing multiple analyte specimens using an analytical column containing a selective adsorbent media. A carrier fluid flows through the column. The method involves introducing a first analyte specimen into the analytical column at an initial temperature. The analytical column is then heated to an intermediate temperature to cause the first analyte specimen to partially travel into the column. The analytical column is then cooled back to the initial temperature, followed by introduction of a second analyte specimen into the analytical column. The analytical column is then heated to a final temperature greater than the intermediate temperature, during which heating analytes from the first and second analyte specimen concurrently and discretely travels through, and sequentially elutes from, the analytical column. The method results in discrete bands of analyte being loaded at spaced intervals within the column, and can be used to load a multiplicity of samples for concurrent analysis.

Abstract: A method of detecting gluteraldehyde adulterant in a urine sample. An aliquot of urine is inserted into an automatic chemical analyzer and a spectrophotometric absorbance reading is taken. Thereafter, the aliquot is mixed with a reagent mixture containing a carbonyl indicator and a second spectrophotometric absorbance reading is taken and compared to the first reading.

Abstract: The invention provides a method for determining whether a compound inhibits acetohydroxyacid synthase. The invention further provides a method for determining whether a plant is resistant to an acetohydroxyacid synthase inhibiting compound.