Abstract: A method for the direct quantitative determination of LDL-cholesterol in a sample of blood plasma which involves selective adsorption of lipoproteins on silica, removal of high density lipoproteins by incubation in a suitable detergent solution, extraction of the remaining LDL-cholesterol by another detergent and determination of the LDL-cholesterol by spectrophotometric analysis.

Abstract: A precipitation reagent for use in analytical systems for the determination of hydrophobic analytes in a biological test sample, particularly analytical systems employing specific binding proteins for such analytes. The precipitation reagent precipitates interfering proteins, hemoglobin, and other interfering substances from a biological test sample while, at the same, maintaining hydrophobic analytes in solution and minimizing the denaturation of specific binding proteins, such as, for example, antibodies, which may be present in an immunoassay system. The precipitation reagent comprises a zinc salt, a glycol, and a straight or branced alcohol from about 1 to 4 carbon atoms, and may optionally contain an acid. A preferred precipitation reagent comprises zinc sulfate, methanol and ethylene glycol, and is particularly useful in a fluorescent polarization immunoassay for the determination of hydrophobic analytes, especially cyclosporine.

Abstract: The present invention provides a metal ion scavenging procedure and antibody compositions for radioimmunoscintigraphy and cytotoxic radioimmunotherapy having chelator concentrations of greater than about 10.sup.-4 M which are optimized with respect to their metal binding capacity such that highly efficient labelling of the antibody is achieved in a simple one step procedure using readily available sources of radiometal ions.

Abstract: This invention relates to safe and effective methods for the extraction of nucleic acids. In particular, methods are described for isolating nucleic acid from a sample containing a biological mixture of nucleic acids and other biological compounds wherein the sample is combined with an extraction solution containing at least one organic compound such as benzyl alcohol or a benzyl alcohol derivative to form an aqueous and non-aqueous phase. The nucleic acid is isolated from the aqueous phase. Preferably, the resulting combined solution also contains bentonite, as defined below. Typically, the sample will first be combined with a lysing agent before extraction. The lysing agents preferred are chaotropic salts such as guanidinium hydrochloride and guanidinium isothiocyanate.

Abstract: A method for the liberation of polysaccharide antigens from bacteria or fungi in biological probes or in grown cultures of these probes is described. In the majority of cases such a liberation is necessary in order that subsequently the polysaccharide antigens can be determined immunologically in a manner known per se. This liberation is effected by treating the biological probe or the grown culture with an aqueous phenol solution. A 1-10% phenol solution is conveniently used, with a 2.5% phenol solution being preferred and a 2% phenol solution being especially preferred. The phenol solution is allowed to act on the probe or culture for 5-30%, preferably 15, minutes. No extraction is necessary for the subsequent immunological determination of the polysaccharides.

Abstract: A method for the quantitative determination of micro-organisms or pyrogens which comprises introducing a prescribed amount of a test liquor containing micro-organisms or pyrogens into a total carbon analyzer to obtain a total carbon value A, while removing micro-organisms or pyrogens from the prescribed amount of the same test liquor and introducing the resultant into a total carbon analyzer to obtain a total carbon value B, subtracting the total carbon value B from the total carbon value A and determining micro-organisms or pyrogens basing upon the resulting value, and an apparatus suitable for conducting the method.

Abstract: Compounds having detergent properties are disclosed. When a modifying reagent is brought into contact with these compounds, the detergent properties are decreased. These compounds are useful, for example, as solubilizing agents for microbial antigens and/or antibodies and for reversibly wetting hydrophobic surfaces. Accordingly, methods are disclosed for increasing the hydrophilic properties of a material, such as a microbial antigen and/or antibody, the methods generally comprising the steps of contacting the material with the compound having detergent properties and a modifiable group, and modifying the compound with a modifying reagent. Kits are also disclosed for use in accordance with this methodology.

Abstract: A method of gathering a library of response patterns for one or more sensor arrays used in the detection and identification of chemical components in a fluid includes the steps of feeding samples of fluid with time-spaced separation of known components to the sensor arrays arranged in parallel or series configurations. Modifying elements such as heating filaments of differing materials operated at differing temperatures are included in the configurations to duplicate operational modes designed into the portable detection systems with which the calibrated sensor arrays are to be used. The response patterns from the known components are collected into a library held in the memory of a microprocessor for comparison with the response patterns of unknown components.

Abstract: A material and method are described to reduce the non-specific binding of a labelled material, wherein the labelled material comprises a fluorochrome and a specific binding pair member. The invention is particularlly suited to the lysis of peripheral blood wherein a labelled material is used to identify and detect cell populations within a sample of blood.

Abstract: A method for determination of biological activity of AT III by measuring coagulating time of blood plasma comprises mixing a specimen having AT III free-extrinsic coagulation factor-containing plasma, heparin and a prothrombin time-measuring reagent or a factor X-activating reagent and then measuring the coagulation time, and a reagent and plasma to be used therefor.

Abstract: Nucleic acid fragment capable of hybridizing to rRNA of Listeria monocytogenes and not to rRNA of Bacillus subtilis.

Abstract: A new and improved test device and method of determining the presence or concentration of a peroxidatively active substance, such as hemoglobin, in a test sample are disclosed. The test device includes a test pad comprising a suitable carrier matrix incorporating an indicator reagent composition capable of interacting with a perioxidatively active substance to produce a detectable or measurable response. In addition, a new and improved indicator reagent composition, comprising an indicator dye, such as a redox indicator, like a benzidine indicator; a hydroperoxide; an amine borate compound having the general structural formula: ##STR1## wherein R.sub.1, R.sub.2, and R.sub.3 are, independently, methyl groups or ethyl groups, and m, n and p are numerals ranging from one to about three; a buffer, is incorporated into a suitable carrier matrix to provide a more accurate and trustworthy assay of a test sample for a peroxidatively active substance.

Abstract: A method for measuring the amount of polyamines in a biological sample is provided. The method comprises utilizing diamine oxidase and/or polyamine oxidase, aminoalkylaldehyde dehydrogenase and NAD.sup.+ or NADPH.sup.+, wherein the improvement comprises carrying out the method in the presence of an acidic aromatic compound.

Abstract: The present invention is directed to the elimination of ascorbic acid interference in assay systems, particularly assay systems based upon oxidase-peroxidase coupled reactions. When ascorbic acid is present in a sample, it can act as a reductant thereby interfering with an assay's reagent system. The present invention eliminates this inteference by quickly oxidizing any ascorbate thereby preventing ascorbate from acting as an unwanted reductant. The ascorbate is oxidized using a dual oxidant system comprising a water soluble polymer bound to Cu.sup.+2 and an organic or inorganic oxidant such as chromate, peroxide, or a N-halo derivative. This invention is surprisingly selective and generally will not itself interfere with the assay's reagent system. Furthermore, the present invention is so fast and efficient that it can be incorporated into a convenient format, such as a conventional "dip-and-read" reagent test strip system.

Abstract: The invention relates to a process for the in vitro detection of a determined RNA, particularly of a mRNA connected with a genetic abnormality in a biological material. This process comprises a treatment of the cells contained in that material for the sake of releasing their cellular components and of exposing the RNAs yet without denaturing other nucleic acids, and then the detection operation comprising contacting RNA sought to be detected, in presence of the other cellular components, with a nucleotidic sequence complementary of the RNA sought.

Abstract: The specification discloses a fecal occult blood test device capable of determining whether the blood found during the test originated in the upper or lower gastrointestinal track. A fecal sample is applied to a test medium charged to be differentially attractive to blood components originating in the upper and lower gastrointestinal track respectively. A solvent is applied to the test specimen to cause differential migration of the blood components and an indicator is then applied to indicate the presence of the blood components, if any.

Abstract: A method of determining the nucleotide sequence of a DNA molecule of arbitrary length as a single procedure by sequencing portions of the molecule in a fashion such that the sequence of the 5' end of the succeeding contiguous portion is sequenced as the 3' end of its preceeding portion is sequenced, for all portions, where the order of contiguous portions is determined by the sequence of the DNA molecule.

Abstract: The process for the removal and qualitative analytical determination of cyanide in cyanide-contaminated soils consists of introducing biologically degradable organic acids into the soil while blowing a gas stream therethrough and subsequently oxidizing the hydrocyanic acid liberated thereby, until no hydrocyanic acid and nor ammonia are detectable in the emerging gas stream. Preferably, the process is carried out by blowing carbon dioxide and compressed air into said soil. The process is also suitable for indirectly detecting pollutants associated with cyanide.

Abstract: Unsegmented, continuous flow analysis, FIA, has been modified for automated measurement of the amounts of metal and metalloids with volatile hydrides. The sample is injected into a continuous carrier flow of acid, and upon reaction with sodium borhydride in a mixing coil, a gaseous hydride is generated which is blown with a gas flow to a detector, preferably an electrically heated quartz tube, and the atomic absorption is measured. The chemical interferences from other substances have been eliminated to a substantial degree by kinetic discrimination. Samples of about 1-100 nanograms can be determined at a rate of 180 samples per hour and with a detection limit in the sub-ng range.

Abstract: A process for determining the concentration of a component, such as glucose, uric acid or polyamine, in a body fluid, such as urine, blood, blood serum, blood plasma, saliva or gastric juice, includes processing the body fluid with a catalase or an immobilized catalase for decomposing hydrogen peroxide included in the body fluid. When the body fluid is processed with the calalase, an inhibitor which inhibits the reaction between the catalase and the component is added to the body fluid after processing with the catalase. The process also includes processing the body fluid with a strongly basic anion exchange resin. When the concentration of polyamine in the body fluid is measured, the body fluid is processed with an acylpolyamineamido hydrolysis enzyme for converting acetylpolyamine into polyamine in the body fluid. After processing the body fluid by the these operations, hydrogen peroxide produced by the reaction between an oxidase and the component is measured.

Abstract: A process for the determination of fructosamine in body fluids by the reaction of a sample solution with a color reagent, wherein the sample liquid is mixed with a buffer solution having a pH value of from 9 to 12, a color-forming reagent and uricase, as well as with at least one detergent, and the chronological change of the extinction is measured kinetically in a temperature range of from 20.degree. to 40.degree. C. at the earliest after 5 minutes.

Abstract: A method of forming an amino acid thiohydantoin from an N-protected amino acid or the C-terminal amino acid of an N-protected peptide. The amino acid is activated by reaction with a ketenimine, and the activated ester is converted to the thiohydantoin by reaction with silyl or pyridine isothiocyanate. The ketenimine is generated by treating an N-substituted isoxazolium compound, such as Woodwards Reagent K with a base, preferably in the presence of the amino acid. Also disclosed is a solid phase support having a derivatized N-substituted isoxazolium or ketenimine group for use in the method.

Abstract: A method for measuring creatine in a sample by the use of creatine amidinohydrolase which comprises decomposing the N-ethylglycine present in the sample enzymatically and thereafter reacting sarcosine oxidase upon the sample; and a reagent for use in the measurement of creatine comprising the first reagent and the second reagent, wherein the first reagent comprises a sarcosine oxidase of which Km value to N-ethylglycine at pH 8, 37.degree. C. is 20 mM or below and catalase or comprises said sarcosine oxidase, a hydrogen donor oxidatively condensable with 4-aminoantipyrine and peroxidase and the second reagent comprises creatine amidinohydrolase, a sarcosin oxidase of which Km value to N-ethylglycine at pH 8, 37.degree. C. is 50 mM or above, peroxidase and a color reagent for H.sub.2 O.sub.2.

Abstract: The instant invention is a process for the recovery from an aqueous solution of water soluble biopolymers, in particular polysaccharides, gums, agar, agarose and starches by the addition of polyoxide solution to the biopolymer containing solution. The biopolymer is then separated and collected.

Abstract: The instant invention is directed to a method for determining the concentration of sulfonate and/or polycarboxylate compounds in an aqueous solution comprising:(a) adjusting the pH of a portion of the aqueous solution to less than 3.0 when measuring sulfonate concentration or to between 3.0 and 12.0 when measuring polycarboxylate concentration;(b) adding an effective amount of an aqueous solution containing a metachromatic dye to the pH-adjusted portion of Step (a);(c) measuring the absorbance of the admixture resulting from Step (b) at a wavelength between 300 nm and 700 nm; and(d) comparing the absorbance from Step (c) with absorbances of standard samples containing known concentrations of sulfonate and/or polycarboxylate compounds and said effective amount of the dye solution of Step (b), thereby determining the sulfonate and/or polycarboxylate concentration of the portion of Step (a).

Abstract: Quenching luminescence of the tris(4,7-diphenyl-1,10-phenanthroline)ruthenium(II) perchorate, immobilized in a silicone rubber by oxygen is shown to be an accurate and precise method for measuring oxygen concentration in solutions and in the gas phase. Quenching can be quantitated by either lifetime or intensity quenching measurements. Strong aqueous acids and bases, complexing agents, oxidants, and reductants do not penetrate the hydrophobic polymer and, therefore, do not affect the response. Gaseous interferents, such as H.sub.2 S, anesthesia gases (e.g. N.sub.2 O, Halothane), and fluorocarbons do not affect the response. Chlorine and especially SO.sub.2 cause strong, but reversible interference presumably because of electron transfer quenching. A system with a response time of less <0.2 s is disclosed, which is adequate for the monitoring of breathing subjects.

Abstract: A method and a test kit for rapidly determining the presence of functional cellular steroid receptors by assaying a tissue sample for nuclear steroid or antisteroid binding is disclosed which comprises treating the tissue with collagenase, incubating the isolated cells with a labelled steroid or a labelled antisteroid capable of complexing said receptors and measuring the bound nuclear radioactivity and the DNA of the isolated cellular nuclei.

Abstract: C1-inhibitor (C1-Inh), the major regulatory protein of the classical pathway of complement activation, can be purified in a new, simplied three step procedure which includes PEG fractionation, jacalin-agarose chromatography and hydrophobic interaction chromatography on phenyl-Sepharose which takes advantage of the marked hydrophilicity of the inhibitor. This procedure has major advantages over those which have been the most frequently used. This method may be highly adaptable to bulk purification for clinical use or for performing analytical or functional studies on genetically or pathologically altered C1-Inh from clinical specimens.

Abstract: The method of this invention is directed to the rapid preparation of a whole blood sample for photooptical analysis. In the preferred embodiments of this method, a whole blood sample, lytic reagent system and immunological stain (optional) are contacted with the sample in a common reaction vessel (i.e. cuvette or test tube), with gentle asymmetric vortex mixing, so as to maintain the particulate matter of the sample at an essentially homogeneous concentration throughout the sample. An aliquot of the contents of the reaction vessel can, thereafter, be analyzed for identification and/or quantification of the analyte of interest.

Abstract: A method for measuring the halogenated organic compound content, e.g., polychlorinated biphenyl ("PCB") content, of soil samples may effectively be carried out with an inexpensive, disposable (that is, single-use) field test kit. The method includes contacting a weighted soil sample suspected of containing PCB or some other organohalogen contaminant with a pre-mixture of water and an organic solvent in which water is slightly soluble. The water extracts any inorganic halides which may be present and would adversely affect the accuracy of the test. The organic solvent wets the moist soil sample sufficiently to extract any PCB therein. The resultant organic solvent phase is separated from the soil sample and aqueous phase, dried by passage through a moisture-adsorbent material to remove or at least greatly reduce its moisture content, and analyzed by means of a color-change titration to determine halide content, and thereby the PCB (or other organohalogen) content, of the soil sample.

Abstract: Disclosed is an improvement relating to adhesion of samples onto a surface for nucleic acid hybridization assay to detect a target polynucleotide. In one aspect, the invention provides a method of adhering a tissue, cell or other target polynucleotide-containing sample to a substrate under nucleic acid hybridization assay compatible conditions. In another aspect, the method comprises a hybridization assay procedure. Also disclosed are kits for performance of such procedures.

Abstract: An assay method for the detection of Factor XIII in plasma is disclosed in which a primary amine derivative of biotin such as preferably 5-(biotinamido) pentylamine is incubated with a glutamine substrate and activated Factor XIII (Factor XIIIa) to form a biotinylated product which may be measured by convention detection assays. In a preferred embodiment, the biotinylated product is bound to a well in a microtiter plate or other solid support and the product is measured by a colorimetric assay which may be read by an automated spectrophotometric plate reader.

Abstract: A process for measuring the amount of stable-type glycated hemoglobin in a sample using high performance liquid chromatography, comprising heating a sample diluted with a hemolysis agent containing a reagent for the removal of unstable-type glycated hemoglobin to achieve the removal of the unstable-type glycated hemoglobin, and analyzing the sample by high performance liquid chromatography.

Abstract: A single color determination method of quantization of the amount of fructosamine in a sample such as serum by removing other interfering reducing agents and developing a color with a coloring agent such as tetrazolium salt.

Abstract: This invention relates to a novel method for assaying 1,5-anhydroglucitol, which is expected to serve as a marker for diabetes, and a kit therefor. More particularly, it relates to:(1) a method for assaying 1,5-anhydroglucitol, which comprises selectively removing sugars from a specimen containing 1,5-anhydroglucitol; allowing pyranose oxidase or L-sorbose oxidase to act on 1,5-anhydroglucitol contained in the sample thus obtained in the presence of oxygen; and determining 1,5-anhydroglucitol from the amount of the hydrogen peroxide thus formed; and(2) a reagent kit for assaying 1,5-anhydroglucitol which comprises an agent for removing sugars, a reagent for detecting hydrogen peroxide and an enzyme for oxidizing 1,5-anhydroglucitol.

Abstract: New and substantially improved methods for the detection of bacteria, bacterial fragments and/or bacterial antigens are described. Novel methods for treatment of rheumatoid arthritis, "essential" hypertension and a variety of diseases found to be associated with bacteriuria are also described. Additionally, the specification discloses that the new and improved methods for direct microscopic examination are advantageously used for examination of formed elements in samples of other body fluids.

Abstract: Disclosed are methods of rapidly and accurately detecting a compound-of interest, such as a toxic drug, in a body fluid. A liquid sample containing various native constituents and an anticipated exogenous chemical compound is obtained from the body. The sample is then subjected to analysis by ion mobility spectrometry to determine the presence of the exogenous chemical compound or related metabolite therein. The method may further include the step of separating the compound-of-interest from said native constituents in said fluid sample prior to analysis.

Abstract: A method of measuring or controlling ozone concentration by ultraviolet ray absorptiometry, includes charging air into a testing tank with its temperature controlled, measuring the disturbing gases generated from testpieces such as rubber samples inside the testing tank by regarding them as ozone, subtracting a value representative of the disturbing gases with a calculation circuit from a value indicative of the preexisting state in the tank to set the ozone concentration at zero, generating a necessary quantity of ozone with an ozonizer by using the zero ozone concentration as a reference point, suspending the generation of ozone after the passage of a predetermined time, measuring once again to obtain a new ozone concentration zero value, adjusting the ozone concentration zero value to the new value if there has been a change in the amount of disturbing gases generated, and repeating at least once the operation described above to regulate the ozone concentration to a desired ozone concentration.

Abstract: A method and apparatus for determining, by use of ion chromatography, a microconstituent contained in a major constituent as impurities present in the major constituent. The invention causes only that portion of the effluent from the detector, shown on an ion chromatograph, that corresponds to the neighborhood of the microconstituent to be led again to the collecting valve. Thus, the microconstituent of the solution can be determined quickly and easily, without reference to the kind of microconstituent being tested.

Abstract: A method for reducing the occurrence of falsely elevated results in a peroxidase-catalyzed, enzyme assay is described. Interference in an assay caused by blood or bood products in a clinical specimen is eliminated or reduced by reacting the specimen with an oxidizing agent such as sodium hypochlorite, hydrogen peroxide or sodium meta-periodate.

Abstract: A process for the detection of carbonyl sulfide in a gas such as carbon dioxide is provided. The process comprises providing a known volume of gas to be analyzed and removing any hydrogen sulfide from the gas as by passage through a lead acetate column. The carbonyl sulfide is then converted to hydrogen sulfide. Preferably, this is accomplished by passage of the gas through acidified water and subsequent reaction by contact with an alumina hydrolysis catalyst. The converted H.sub.2 S is then detected and measured. The amount of hydrogen sulfide detected represents an equilmolar amount of carbonyl sulfide present in the original volume of gas.

Abstract: A method of removing a constituent of a biological fluid including a blood component, said method including flowing the biological fluid past one side of a first semipermeable membrane; flowing solution containing a first precipitation agent past a second side of the membrane so as to cause transfer of the precipitation agent through the membrane to the biological fluid so as to improve precipitation characteristics of the fluid; and precipitating the constituent from the biological fluid. Also disclosed are maintaining a lower pressure in a biological fluid in a dialyzer than in dialysate at all portions of a membrane in the dialyzer and adding a continuously flowing stream of concentrated precipitation agent to a continuously flowing stream of a biological fluid.

Abstract: A method is provided for the rapid base sequencing of DNA or RNA fragments wherein a single fragment of DNA or RNA is provided with identifiable bases and suspended in a moving flow stream. An exonuclease sequentially cleaves individual bases from the end of the suspended fragment. The moving flow stream maintains the cleaved bases in an orderly train for subsequent detection and identification. In a particular embodiment, individual bases forming the DNA or RNA fragments are individually tagged with a characteristic fluorescent dye. The train of bases is then excited to fluorescence with an output spectrum characteristic of the individual bases. Accordingly, the base sequence of the original DNA or RNA fragment can be reconstructed.

Abstract: An apparatus for quantitative determination of trihalomethanes comprises a separation unit containing two channels in contact with each other via a microporous membrane that will not react with trihalomethanes, a reaction unit for heating a carrier solution that has passed through the separation unit, a cooling unit for cooling the carrier solution that has undergone complete reaction; and a detection unit for determining the quantity of a fluorescent substance in the carrier solution. A method for quantitative determination of trihalomethanes comprises flowing a sample solution or a mixture thereof with a reducing agent through one of the two channels in the separation unit, flowing the carrier solution through the other channel, heating the carrier solution that has passed through the separation unit and to which an alkaline nicotinamide or a derivative thereof has been added, cooling the carrier solution, and subjecting the cooled solution to fluorimetry.

Abstract: The present invention provides a process for the detection of redox reactions by introducing a redox reagent system into a test system, wherein a soluble iodate is additionally added to the test system in an amount which is in excess of the highest amount of disturbing reducing agents present in the test system.The present invention also provides a diagnostic agent for the detection of redox reactions containing a redox reagent system, wherein the test system used additionally contains an iodate which is soluble therein in an amount which is in excess of the highest amount of disturbing reducing agents present in the test system.

Abstract: The present invention is directed to an agent and method for eliminating ascorbate interference in reagent systems, particularly assay systems using oxidase/peroxidase coupled reactions or similar type redox chemistry. The present invention can also be used in reagent systems involving enzyme/substrate reactions in which the substrate is sensitive to reductants such as ascorbate. The agents of this invention comprise water insoluble cerium (IV) compounds.

Abstract: Serum samples for vitamin B.sub.12 analysis can be pretreated using a combination of peroxy acid and dithiothreitol. The pretreatment makes vitamin B.sub.12 bound to serum binding proteins available for analysis by any of a variety of currently available assay techniques. The pretreatment finds particular use in an assay using solid phase intrinsic factor as a specific binding protein.

Abstract: A filter providing at least two different filtering pore sizes for coarse and fine filtering, and a kit containing such filter along with an immunoassay test device containing a membrane. The membrane is used to separate bound immunoassay labels from free labels. The coarse and fine filtering are provided preferably by two different, serially arranged filters, the filter with the fine pore size being selected with a pore size similar to that of the membrane of the assay device.

Abstract: A rapid, microwave-based Kjeldahl digestion method wherein microwave energy is applied to an acid/sample mixture at the beginning of, and thereafter during the digestion. After the application of microwave energy is discontinued, the digestate is diluted by pulsed addition of water, followed by continuous addition of water. Dilution in this manner prevents a sudden surge in gas evolution, and eliminates the need for an intervening cooling step, thereby reducing processing time. Also provided is a method for fat separation from a fat-containing protein sample during the digestion.

Abstract: Method and apparatus for the detection and quantitation of polychlorinated biphenyls (PCB's) utilizing sample preparation by treatment with predetermined quantities of sulfuric acid and lower alkane, in which the alkane--extracted phase is subjected to chromatographic separation of PCB components (116) and electron capture detection of the separated PCB components (118), and in which the detector response is analyzed by pattern recognition comparison (316) for determination and quantitation of PCB's presented in the sample with stored data for standard PCB mixtures.