Abstract: A method determines the concentration of a chemical of interest in a solution. A permeable membrane is placed in the solution and a ligand is exuded through the membrane to continually renew the ligand at the surface of the membrane which is in contact with the solution. Complexes of the ligand with the chemicals of interest are formed where the ligand renewed membrane is in contact with the solution. Illuminating the ligand renewed membrane with radiation from a distance from the membrane induces a fluorescence by the formed complexes on the ligand renewed membrane by the illuminating radiation. The fluorescence from the illuminated complexes on the ligand renewed membrane are detected from a distance from the membrane to provide a determination of the concentration of the chemical of interest in the solution.

Abstract: A method for detecting mercury amalgamation of an aluminum body includes the steps of contacting a surface of the aluminum body with an electrolyte, and simultaneously contacting the electrolyte with a reference electrode. The reference electrode is formed of a metal which is more electronegative than the aluminum body being tested, such that the electrolyte creates an electrochemical cell between the aluminum and the reference electrode, which cell produces an electromotive potential between the aluminum and the reference electrode. The potential difference is monitored. The potential difference will differ when the aluminum surface contacted with the electrolyte is mercury amalgamated from when no mercury amalgamation is present in the aluminum surface contacted.

Abstract: An improved method for measuring polarized fluorescence emissions compensates for background emissions without separating a fluorescing material from background material contributing background fluorescence. The method is particularly useful in measuring fluorescence from a suspension of cells such as stimulated lymphocytes in the SCM assay, where the intracellular fluorescence is due to the penetration of the cells by a fluorogenic agent precursor and its subsequent hydrolysis. The method involves measuring the horizontally and vertically polarized components of the fluorescence emission at a primary wavelength and at least one secondary wavelength. The secondary wavelength is selected based on the bathochromic shift of the spectrum of the fluorescence emissions from the fluorescing material as compared to the fluorescence emissions from the background.

Abstract: Method using tetra-aryl porphyrins for and, in particular, 5,10,15,20-tetrakis(4-carboxyphenyl)porphine as a fluorescent tracer for cancers of the lung, and as a radiotracer therefor as a complex with .sup.67 Cu. The latter complex also provides a source of beta radiation for selective destruction of lung malignancies as well as gamma radiation useful for image analysis of the situs thereof by single photon emission computed tomography, as an example, both in vivo. Copper-64 may be substituted for the .sup.67 Cu if only radiotracer characteristics are of interest. This lighter isotope of copper is a positron emitter, and positron emission tomography techniques cna be used to locate the malignant tissue mass.

Abstract: Use of a lithium salt, particularly lithium thiocyanate, as an agent for lysing red blood cells and denaturing hemoglobin in the performance of an immunoassay to detect the relative amount of a hemoglobin derivative in a blood sample. The method is particularly useful in the determination of hemoglobin A1c. The method rapidly releases hemoglobin from red blood cells by lysis and exposes the epitope that is characteristic of the A1c form. Low concentrations of the lithium salt provide rapid release and denaturation of hemoglobin without the need for dilution prior to the performance of the immunoassay.

Abstract: Periodical sterilization is usually needed in the ultrapure water line provided in an ultrapure water-producing system or plant to kill some occasionally occurring viable cells of microorganisms in the ultrapure water as produced or being produced and thereby keep the ultrapure water under germ-free conditions. Now, it is discovered that an aqueous solution containing 1 to 100 ppm of hydrofluoric acid is effective to sterilize the ultrapure water line and is advantageous over the conventional sterilization agents such as aqueous hydrogen peroxide and sodium hypochlorite which were employed normally for the sterilization of the ultrapure water line.

Abstract: A reverse-phase HPLC method is disclosed which allows the separation of DPU and PTH-Trp and, therefore, the correct assignment of tryptophan residues in an amino acid sequence. The method is based on a modification of the conventional HPLC gradient commonly used to elute and separate all PTH amino acids of interest in automated and manual sequencing. In one embodiment, using automated instruments manufactured by Applied Biosystems, gradient modification is achieved by changing the manufacturer-supplied gradient program which controls the operation of the HPLC pumps in the instrument. Using the methods of the present invention, the correct and reliable assignment of tryptophan residues is possible and was reproducible over time, even with small sample sizes.

Abstract: Measuring of soil gas flux. Particularly a method of measuring soil gas concentration and emission flux during a period of post-compression of the earth's crust. The method includes observing gravitational acceleration on the surface of the earth, as defined by crustal tension and compression and as induced by the Sun and Moon, compensating for variation in acceleration due to geographic location of said observing, locating said crustal tension in the form of a bulge on the surface of the earth, then post-compression measuring of soil gas concentration and emission flux rate during both the long term (approximately 1 to 10 days) and short term (approximately 1 to 8 hours) of maximum soil gas emission.

Abstract: A method for monitoring unusual signs such as partial heatings and partial electric discharges in an apparatus to be monitored, in which a sealed gas is enclosed into a tank containing the apparatus, and at least one of monitor gases represented by formulas (I) and (II),C.sub.n X.sub.2n (I)C.sub.n X.sub.2n+2 (II)wherein X is at least one of H, F, Cl, Br and I, and n is one of 2, 3, 4 and 5, is charged into the tank, and in which a reaction product gas of the monitor gas, generated due to an abnormality of the apparatus to be monitored, is detected using a detector. A gas-charged apparatus including an unusual sign monitor is also disclosed.

Abstract: General classes of 2-thiazolyl tetrazolium salt compounds have been found to be characterized by a reflectance spectrum exhibiting an extended plateau above about 600-650 nm. Such compounds are useful as chromogenic indicators for reducing substances such as NADH. The reflectance plateau confers improved accuracy to analytical assays, particularly for the determination of analytes of medical diagnostic significance, in which a colorimetric response on a reagent carrier matrix is measured by reflectance.

Abstract: A closure device for fermentation test tubes or flasks comprises a cylindrical cap which fits snugly over the mouth and neck of a test tube or flask to maintain the sterility of the tube or flask contents while permitting the free flow of gases into and out of the tube or flask. An aperture in the end cap of the closure device permits free access to the tube or flask contents for sampling and is closed by a moveable aperture cover.

Abstract: A reagent format having an inverse funnel shaped body which includes a central capillary tube that opens into a flow passageway. The flow passageway is formed, in part, by providing a recessed flow surface at one end of the inverse funnel shaped body which is surrounded by a stepped shoulder. A test substrate, such as reagent film, is secured to the shoulder so as to form one surface of the flow passageway. The device is suitable for both drawing and spreading a fluid test sample onto a test substrate in one step. Additionally, one or more small diameter vent passageways open into the flow passage to allow for air to escape when fluid is drawn into the flow passage through capillary action. The pen-shaped body is also formed of a clear or translucent material such that the flow of the test fluid can be observed by the user.

Abstract: Surfactants bound to a ligand and dissolved in a single phase aqueous solution form a precipitate when a multivalent antiligand is added to the solution. This invention can be used in an affinity precipitation test procedure (and kit) for detecting the presence or absence of a multivalent antiligand in a sample suspected of containing the multivalent antiligand, in an affinity precipitation inhibition test procedure (and kit) for detecting the presence or absence of a target ligand in a sample suspected of containing the target ligand, and in a process for separating a multivalent antiligand from a crude material containing the multivalent antiligand.

Abstract: Certain water-compatible reducible compounds are useful in analytical compositions and elements for assay of various analytes, e.g. microorganisms. These compounds comprise a moiety which provides a detectable species (e.g. a dye) when released from the compound at physiological pH. Further, these compounds are aromatic derivatives or quinones having water-compatibilizing substituents which allow them to be used in compositions without the use of surfactants.

Abstract: Improved process control is achieved in processes for which it is useful to control variable process conditions based upon on-line determinations of the concentration of weak acids and weak bases, or their soluble salts, in liquid streams of the processes. For example, amine system energy savings and waste treatment system control improvements are taught.

Abstract: For the simultaneous measurement of two parameters of a liquid or gaseous sample, in a fluorescence measuring device in which the influence of the aging processes of the indicator substance and the fluctuations in the light intensity of the excitation light source are to be avoided, it is proposed that the change in the first parameter to be measured is obtained from the change in the ratio of two intensity values, determined for different wavelengths of the excitation and emission spectrum of the indicator substance, and the change of a second parameter is obtained from the change in the decay time t of the fluorescence radiation of the same indicator substance from the group of aromatic hydrocarbons, the aromatic heterocycles and the metal organic complexes.

Abstract: The present invention is directed to a simple and inexpensive liquid or dry reagent assay system for detecting nanomolar amounts of manganese in body fluids in microgram per liter concentrations. More specifically, the manganese assay of this invention is directed to the optical detection of a chromogenic reaction, such as the oxidation of a redox indicator, catalyzed by a manganese porphyrin complex.

Abstract: The invention is a method for the detection of molecules in a liquid medium involving the trapping of solid support conjugates. The reactants of the present invention are drawn upward through the device by capillary action against the force of gravity.

Abstract: A fixative solution for fixing biological smears, such as blood smears, to a slide for subsequent staining of the smear, which can be used in automated slide staining equipment, includes a fixative liquid, a stabilizing agent to reduce water spotting problems during fixing and/or to stabilize cellular components of the smear, and a solubilizing agent for maintaining the stabilizing agent in solution in the solubilizing agent after evaporation of the fixative liquid to thereby prevent formation of the solid residue normally formed by the stabilizing agent upon evaporation of the fixative liquid. The invention also includes the method fo preventing formation of a solid residue upon evaporation of the fixative liquid from a fixative liquid-stabilizing agent solution by the addition of a solubilizing agent thereto. The mixture of the stabilizing agent and solubilizing agent can be made as a concentrated additive to be added to a fixative liquid prior to use.

Abstract: The concentration of weak acid and weak base constituents, or their soluble salts, in liquids is determined by passing succeeding samples of constant volume to a separation zone wherein target constituents are volatilized by reagents, then volatilized analytes are stripped from the liquid matrix and carried to a detection zone at a constant flow rate, wherein signals proportional to the variations in individual target analyte concentrations between succeeding samples are generated.