Abstract: Methods and apparatus for inferring protein binding based on rotational diffusion of a collection of fluorophores.

Abstract: The invention relates to a novel method for diagnosing the sulfur nutrition state of a plant by measuring the content of certain mineral nutrients in the leaves.

Abstract: A flowable dry powder composition comprising a mixture of diphenylcarbazide particles and glass bubbles; kits containing such compositions; methods of filling containers with such compositions; and, methods of using such compositions in the detecting of hexavalent chromium.

Abstract: The present invention provides an electrochemical sensor having a solid electrically conductive substrate and a compound immobilized thereon which has binding affinity for an analyte species to be detected and also displays electrochemical behavior which is modified upon binding of that analyte species, so that binding of an analyte species can be detected by measuring electrochemical properties, such as by voltammetry. Desirably the immobilized compound contains both a first moiety with binding affinity for the analyte and a separate second moiety which is a redox system whose electrochemical oxidation/reduction properties become modified when the first moiety binds the analyte. The analyte binding moiety may be a diol or polyol and preferably is a sugar. The electrochemical sensor finds use in methods of analyzing reservoir and process fluids, particularly at a subterranean location. The electrochemical sensor may be a component of a downhole tool, adapted for deployment downhole.

Abstract: The present invention relates to gas sensors using doped ferroelectric materials. The sensors can be fabricated as an array where different portions of the array can operate at different independently controlled temperatures to detect different gas phase components of a gas sample. Preferred embodiments can be used for the diagnosis of conditions, such as, diabetes.

Abstract: Reagents and methods are disclosed for detection of oxidizers and inorganic salts and other analytes of interest. The reagents can interact with their target analytes, especially oxidizer compositions or oxidizer-based explosives, to selectively enhance their ionization yield, interacting by chemical reaction or by forming an associative adduct which facilitates their detection. For example, the reagents can adduct with the counter-ion of the intended analyte for improved direct detection and/or react chemically via acid-base reactions to produce a new product for detection. In another aspect of the invention, reactive reagents and methods are also disclosed that facilitate indirect detection of the analyte at lower temperatures based on reduction-oxidation (redox) chemistry. These reagents are particularly useful in detecting oxidizer analytes.

Abstract: A method for analyzing a metal material includes electrolyzing a metal sample in an electrolytic solution, immersing a remaining portion of the metal sample taken out of the electrolytic solution in a dispersible solution to separate at least one substance selected from the group consisting of precipitates and inclusions attached to the remaining portion of the metal sample, filtering the dispersible solution containing the at least one separated substance through filters having straight pores and a porosity of 4% or more to obtain residues trapped on the filters and filtrates, and analyzing at least one of the residues and the filtrates.

Abstract: A comprehensive approach for interpretation of the multiple spiking isotope dilution results is described herein. It has now been found that a method of multiple spiking isotope dilution analysis for mass spectrometry is possible using an approach that permits precise and simultaneous characterization of m substances from a sample even if species inter-conversion (degradation and formation) has occurred prior to separation. Advantageously, initial and final amounts of involved analytes, conversion extent, conversion degree and rate constants from the results of a single quantitation experiment may be obtained with the present method. In a particularly advantageous embodiment, uncertainty in the characterization of the substances may be estimated more accurately by also estimating increase in the uncertainty due to inter-conversion of the analytes.

Abstract: A method for determining chromium content in a tungsten matrix with singly or simultaneously added chromium and vanadium, characterized in that a test sample is subjected to melting with sodium peroxide and hot water leaching; meanwhile said sodium peroxide is also used as an oxidizing agent to oxidize all the chromium to high valences; the main body of tungsten is coordinated by ammonium hydrogen fluoride to prevent tungstic acid from precipitating; precipitation and turbidity are avoided throughout the analysis, titration can be carried out in a quite clear condition with accurate and reliable results.

Abstract: A flowable dry powder composition comprising a mixture of diphenylcarbazide particles and glass bubbles; kits containing such compositions; methods of filling containers with such compositions; and, methods of using such compositions in the detecting of hexavalent chromium.

Abstract: This disclosure relates to a method for detecting at least one analyte in a tetrachloride sample comprising titanium, tin or silicon tetrachloride; comprising, (a) adding a mixture of water and acid, typically hydrochloric acid, to the sample under conditions effective for forming an aqueous solution of the sample; (b) introducing the aqueous solution of the sample into an inductively coupled mass spectrometer having a cell selected from the group of a reactive cell and a collision cell or both and producing an analyte ion comprising an interfering species; (c) contacting the analyte ion with a gas to produce a product which is substantially free from the interfering species; and (d) detecting and measuring at least one signal from the analyte in the solution. This disclosure further relates to a method for making an aqueous titanium, tin or silicon tetrachloride sample suitable for analysis in using inductively coupled plasma mass spectroscopy.

Abstract: Compositions comprising a tripeptide having the sequence XC1C2; wherein X is any amino acid such that XC1C2 is capable of binding a metal in a square planar orientation or square pyramidal orientation or both; and wherein C1 and C2 are the same or different; and wherein C1 and C2 individually are chosen from a cysteine and a cysteine-like nonnatural amino acid, as well as metal-XC1C2 complexes and methods for forming such complexes.

Abstract: The present invention relates to a molecular-based system for the optical detection, quantification and detoxification of hexavalent chromium (Cr6+) by reversible metal-substrate electron transfer. More particularly, the invention provides a Cr6+ sensor device comprising a divalent osmium (Os2+)-, iron (Fe2+)- or ruthenium (R2+)-based pyridyl complex capable of changing its oxidation state in response to a reduction of Cr6+ at the presence of H+, thereby causing a reversible and optically readable change in optical properties of said complex. The Os2+-, Fe2+- or R2+-based pyridyl complex used according to the invention can be used for selective detection and quantification of Cr6+, as well as for catalytic detoxification of Cr6+.

Abstract: A method that uses an (DOPC) surfactant based biofilm that reacts with a material in a known manner, and a device that utilizes such a biofilm, to detect a material of interest is provided. The principles of the present invention are particularly useful in detecting/measuring a material that is harmful to a human or to property.

Abstract: The present invention provides an electrochemical sensor having a solid electrically conductive substrate and a compound immobilized thereon which has binding affinity for an analyte species to be detected and also displays electrochemical behaviour which is modified upon binding of that analyte species, so that binding of an analyte species can be detected by measuring electrochemical properties, such as by voltammetry. Desirably the immobilised compound contains both a first moiety with binding affinity for the analyte and a separate second moiety which is a redox system whose electrochemical oxidation/reduction properties become modified when the first moiety binds the analyte. The analyte binding moiety may be a diol or polyol and preferably is a sugar. The electrochemical sensor finds use in methods of analysing reservoir and process fluids, particularly at a subterranean location. The electrochemical sensor may be a component of a downhole tool, adapted for deployment downhole.

Abstract: Processes for reducing hexavalent chromium, Cr(VI) in a chromite ore processing residue matrix and processes for analyzing and determining effective treatment are disclosed.

Abstract: Provided is a method for simply quantitatively determining hexavalent chromium, including: separately bringing a plurality of test solutions into contact with a sample, the plurality of test solutions each containing a color change agent which changes in color upon reaction with hexavalent chromium, and an acid which dissolves the sample, the plurality of test solutions having different contents of the acid from each other; detecting color change in each of the test solutions; and when the color change is detected, specifying a range of content of hexavalent chromium in the sample on the basis of the content of the acid in a test solution with the color changed among the plurality of test solutions.

Abstract: A method for determining vanadium content in a tungsten matrix with singly added vanadium or simultaneously added chromium and vanadium, characterized in that a test sample is subjected to alkaline melting with sodium peroxide and water leaching followed by dry filtering, the chromium and vanadium in the filtrate are firstly reduced to low valences by a reducing agent, i.e. hydroxylamine hydrochloride, then the filtrate is adjusted to an acidity of 4-6 M with nitric acid, the vanadium is oxidized in a cold state to a high valence by potassium permanganate, and the high-valent vanadium forms a ternary complex with tungstate and orthophosphate, the darkness of the color of the ternary complex is directly proportional to the vanadium content, thus the vanadium content is determined colorimetrically, and the interference of chromium is eliminated with the fact that the potassium permanganate in a cold state in the acidic condition for vanadium determination oxidizes the vanadium but not the chromium.

Abstract: A method for determining chromium content in a tungsten matrix with singly or simultaneously added chromium and vanadium, characterized in that a test sample is subjected to melting with sodium peroxide and hot water leaching; meanwhile said sodium peroxide is also used as an oxidizing agent to oxidize all the chromium to high valences; the main body of tungsten is coordinated by ammonium hydrogen fluoride to prevent tungstic acid from precipitating; precipitation and turbidity are avoided throughout the analysis, titration can be carried out in a quite clear condition with accurate and reliable results.

Abstract: The present invention discloses a method and composition for testing the wear on mechanical hardware. During the testing method a metal oxidant is applied the mechanical hardware being tested which deposits onto the mechanical and can be visually detected. One of the properties of the metal oxidant is that it is a substantially non-flow or non-drip medium that can be applied in situ with reduced risk to surrounding hardware.

Abstract: An improved optical method for determining metal or a metal compound thereof in a sample with organic impurities. The optical method comprises of solvating the metal in a liquid medium and then mixing this liquid medium with an optical indicator and then measuring the presence of the metal. The improvement lies in removing any organic impurities by the addition of an additive, where the said additive is removed before the optical indicator is added.

Abstract: The present invention is a new class of fluorescent sensor with unprecedented sensitivity, selectivity and synthetic efficiency for the identification and qualitative and quantitative detection of transition metal ions. The chemosensing properties are based on an internal charge transfer mechanism or photo-induced electron transfer and are effective in vitro. The chemosensor comprises one or more electron donating dipyrrin functionalities linked to an electron withdrawing functionality. The chemosensor forms a stable transition metal complex through internal charge transfer between the electron donating functionality and the target transition metal, which results in measurable fluorescence. Specific examples for sensing zinc and copper ions are described.

Abstract: The invention pertains to a method for determining the presence or absence of at least one chemical substance in a liquid medium, comprising a contacting step of said liquid medium with a device comprising at least one substrate coated, in whole or in part on at least one of its sides, with at least one layer comprising material able to be degraded fully or partly by said chemical substance, said material being chosen from among metals, metal alloys, metal oxides.

Abstract: A standard calibration set having at least three calibration standards. Each standard is a molded article made of a thermoplastic polymer which contains the elements Cd, Cr, Pb, Hg and Br, with the Cr:Pb:Hg:Br:Cd ratio being different in each of the three calibration standards. Further disclosed is a method for manufacturing the calibration standards and their use in X-ray fluorescence analysis.

Abstract: Molecular bioprofiles comprising biologically correlated and relevant analytes that impact the biological state of a human health condition compared to a control population are provided. These molecular bioprofiles are useful in several ways including but not limited to, monitoring a disease or condition's progression, evaluating the impact of an agent or compound on a disease or condition, evaluating the impact of a lifestyle change on a disease or condition and assessing the risk of the disease or condition to a subject. Type II diabetes molecular bioprofiles are of particular interest.

Abstract: A method for analyzing a plurality of amino acids in a fluid sample by a user is provided comprising the steps of introducing the sample into a buffer solution, passing the sample in the buffer solution through a separation column and setting a lithium ion concentration in the buffer to no more than 0.3 mols/L up to a time before ?-aminoisobutyric acid (?-AiBA) is eluted.

Abstract: Proposed is a zirconium crucible used for melting an analytical sample in the pretreatment of the analytical sample, wherein the purity of the zirconium crucible is 99.99 wt % or higher. In light of the recent analytical technology demanded of fast and accurate measurement of high purity materials, the present invention provides a zirconium crucible for melting an analytical sample, a method of preparing such analytical sample, and a method of analysis that enables the analysis of high purity materials by inhibiting the inclusion of impurities from the crucible regardless of difference in the analysts and their skill.

Abstract: The present invention relates to a molecular-based system for the optical detection, quantification and detoxification of hexavalent chromium (Cr6+) by reversible metal-substrate electron transfer. More particularly, the invention provides a Cr6+ sensor device comprising a divalent osmium (Os2+)-, iron (Fe2+)- or ruthenium (R2+)-based pyridyl complex capable of changing its oxidation state in response to a reduction of Cr6+ at the presence of H+, thereby causing a reversible and optically readable change in optical properties of said complex. The Os2+-, Fe2+- or R2+-based pyridyl complex used according to the invention can be used for selective detection and quantification of Cr6+, as well as for catalytic detoxification of Cr6+.

Abstract: There is provided a hybrid and/or complex material or the like which can realize a high-efficient photoelectric conversion material or the like. One aspect of the present invention lies in a dye-sensitized solar cell device 10, characterized by including: a first substrate 11; a first conductive layer 12 formed on the first substrate; a Pt catalyst layer formed on the first conductive layer; an electrolyte layer 13 formed on the Pt catalyst layer; a dye-adsorbed metal oxide layer 14 formed on the electrolyte layer in which 7,7,8,8-tetracyanoquinodimethane is adsorbed to an anatase type titanium oxide; a second conductive layer 15 formed on the dye-adsorbed metal oxide layer; and a second substrate 16 formed on the second conductive layer. According to this composition above, there is obtained a high-efficient dye-sensitized solar cell device in which light can be converted efficiently over wide wavelengths.

Abstract: Provided is a method for simply quantitatively determining hexavalent chromium, including: separately bringing a plurality of test solutions into contact with a sample, the plurality of test solutions each containing a color change agent which changes in color upon reaction with hexavalent chromium, and an acid which dissolves the sample, the plurality of test solutions having different contents of the acid from each other; detecting color change in each of the test solutions; and when the color change is detected, specifying a range of content of hexavalent chromium in the sample on the basis of the content of the acid in a test solution with the color changed among the plurality of test solutions.

Abstract: The method for surface inclusions detection in wrought and finished Nitinol products by immersing them in aqueous solution of 1% to 12% preferably 6% sodium hypochlorite in room temperature of around 25° C. for specify period of time preferably 15 minutes and checking for black flocculent precipitate developing on the surface in case of presence of inclusion. The black flocculent precipitate indicates surface inclusion or inclusions and indicates lack of homogeneousness of material.

Abstract: Provided are a target biomaterial detecting kit and a method of detecting the target biomaterial. The target biomaterial detecting kit includes a guided mode resonance filter comprising a substrate transmitting or reflecting light, a grating layer formed on the substrate, and a capture layer formed on the grating layer to capture a target biomaterial; and a nano complex comprising a nanoparticle head and a connection tail. Therefore, the wavelength peak of a reflection/transmission spectrum of light coming from the guided mode resonance filter can be largely shifted, and thus the presence and quantity of a target biomaterial can be easily detected. Moreover, although the amount of the target biomaterial is small, the target biomaterial can be reliably detected.

Abstract: Disclosed is a method for the quantitative analysis of a metal element contained in a resin material, which permits quantitatively analyzing the harmful substance such as lead contained in a resin material, comprising decomposing the resin material within a container having at least the inner surface formed of a glassy carbon in the presence of an aqueous solution of an oxidizing acid, heating the organic residue of the decomposed resin material so as to convert the residue into an ash, and quantitatively measuring the metal element contained in the organic residue converted into the ash.

Abstract: The present invention is directed to methods for determining electron transfer rates in systems involving metalloproteins. Metalloprotein/substrate electron transfer rates as well as metalloprotein self exchange rates may be modeled. Such electron transfer rates are useful in smart drug design and enzyme engineering.

Abstract: An improved optical method for determining metal or a metal compound thereof in a sample with organic impurities. The optical method comprises of solvating the metal in a liquid medium and then mixing this liquid medium with an optical indicator and then measuring the presence of the metal. The improvement lies in removing any organic impurities by the addition of an additive, where the said additive is removed before the optical indicator is added.

Abstract: This invention provides methods of using ion-detecting microspheres containing an ionphore and a chromoionphore in clinical laboratory instrumentation such as flow cytometry for sample analysis. In one embodiment, the microspheres are contacted with a flowing stream of a sample under conditions that allow the ion-selective ionophores to complex with the ions in the sample, and to cause deprotonation of the chromoionophore. The complexes are then exposed to an excitation wavelength light source suitable for exciting the deprotonated chromoionophore to emit a fluorescence signal pattern. Detection of the fluorescence signal pattern emitted by the deprotonated chromoionophore in microspheres containing the complexes allows for determination of the presence of the target ions in the sample. In one embodiment, lead ion-detecting microspheres are provided that can detect nanomolar levels of lead ions with response times on the order of minutes.

Abstract: It is an object of the present invention to provide an analytical method and analyzer for hexavalent chrome that allows for measuring hexavalent chrome conveniently without using a spectrophotometer and obtaining the objective quantification results. Disclosed herein is an analytical method for quantifying hexavalent chrome by, after adding a reagent for complex formation to a liquid sample to form a colored chelate of hexavalent chrome, then contacting the liquid sample with an adsorbent, and measuring a thickness of a colored layer of the adsorbent.

Abstract: The present invention is directed, in part, to fluorescein-based ligands for detection of metal ions, and methods of making and using the same.

Abstract: A system for quantitatively reducing oxide gases. A pre-selected amount of zinc is provided in a vial. A tube is provided in the vial. The zinc and the tube are separated. A pre-selected amount of a catalyst is provided in the tube. Oxide gases are injected into the vial. The vial, tube, zinc, catalyst, and the oxide gases are cryogenically cooled. At least a portion of the vial, tube, zinc, catalyst, and oxide gases are heated.

Abstract: A method of directed automated analysis of a plurality of analytes of a process solution includes providing a sample of the process solution containing a plurality of the analytes, admixing an enriched isotope spike for each of the plurality of analytes to be analyzed with the process solution sample thereby effecting admixture of the enriched ratio of isotopes with the naturally occurring ratio of each analyte to be analyzed, creating ions from the spikes, introducing the ions into a mass spectrometer for determination of the identity and quantity of each analyte and delivering the information to a microprocessor. If desired, the process solution sample may be diluted and/or subjected to the addition of reagents or standards prior to initiation of the analysis. The ions may be created by an atmospheric pressure ionization interface. The information obtained is processed in a computer which serves to control other portions of the practice of the method.

Abstract: Methods are provided for diagnosing and/or characterizing chronic immune disease activity in a subject. In the subject methods, a sample is obtained from a subject suspected of having or known to have a chronic immune disease. The sample is then assayed for the presence of native Stat-1 protein and/or any lower molecular weight fragments of Stat-1 protein present. The assay results are used to diagnose the presence of chronic immune disease activity and/or characterize chronic immune disease activity in the subject, e.g., to confirm an initial chronic immune disease diagnosis, to determine the stage of the disease, to monitor disease progression, to predict disease attacks, and the like. In certain embodiments, the assay results are also used to predict the effectiveness of a particularly treatment protocol, e.g., to determine whether an interferon based treatment protocol will be effective. In addition, methods of Stat-1 based methods of treating chronic immune disease conditions are provided.

Abstract: The present invention relates to the preparation of a sample. Preferably, the sample is a sample to be analyzed, for example for ingredient content, etc. Preferred samples include foods, cosmetics, paints, coatings, adhesives, tanning agents, fabrics, chemical compositions, dyestuffs, samples subject to forensic studies, etc. Samples prepared according to the invention method are digested in sulfuric acid, nitric acid, and one or more fluoride salts selected from LiF, NaF, RbF, CsF and KF and then preferably subjected to analysis for metal content, etc, for example using atomic absorption (“AA”) and inductively coupled plasma (“ICP”).

Abstract: Provided is a method of lysing a cell or a virus using a free radical. The method includes: applying an electric field to a mixture of a metal ion, a peroxide, and a cell or virus solution to increase the free radical generation, thereby lysing a cell or a virus. In the present method, cell lysis may be efficiently performed using a low electrical energy (several mV to several V). When the present method is applied to a microsystem, cell lysis can occur at a desired time and in a desired space by controlling the electrical energy, thus being suitable to realize a lab-on-a-chip (LOC).

Abstract: The present invention teaches a marker useful for detection and measurement of free radical damage. Specifically, the invention takes advantage of alterations which occur to the N-terminus of the albumin molecule, a circulating protein in human blood, in the presence of free radicals. These alterations affect the ability of the N-terminus of the albumin molecule to bind metals. Methods for detecting and quantifying this alteration include evaluating and quantifying the cobalt binding capacity of an albumin containing sample, analysis and measurement of the ability of albumin to bind exogenous cobalt, detection and measurement of the presence of copper in a purified albumin sample and use of an immunological assay specific to the altered form of serum albumin which occurs following free radical damage.

Abstract: Methods and systems for the concentration and removal of metal ions from aqueous solutions are described, comprising treating the aqueous solutions with photoswitchable ionophores.

Abstract: Described herein are methods for testing an aged surface on an implant, methods for regenerating a hydrophilic and osteophilic surface on the implant and kits therefor.

Abstract: A method for analyzing a plurality of amino acids in a fluid sample by a user is provided comprising the steps of introducing the sample into a buffer solution, passing the sample in the buffer solution through a separation column and setting a lithium ion concentration in the buffer to no more than 0.3 mols/L up to a time before ?-aminoisobutyric acid (?-AiBA) is eluted.

Abstract: The present invention is a new class of fluorescent sensor with unprecedented sensitivity, selectivity and synthetic efficiency for the identification and qualitative and quantitative detection of transition metal ions. The chemosensing properties are based on an internal charge transfer mechanism or photo-induced electron transfer and are effective in vitro. The chemosensor comprises one or more electron donating dipyrrin functionalities linked to an electron withdrawing functionality. The chemosensor forms a stable transition metal complex through internal charge transfer between the electron donating functionality and the target transition metal, which results in measurable fluorescence. Specific examples for sensing zinc and copper ions are described.

Abstract: The present invention is directed, in part, to sensors for detecting metal ions, and methods of making and using the same.

Abstract: In one embodiment, a method of neutralizing the matrix of an acidic solution including at least one metal using a weak anion exchange resin is provided. The method includes the acts of: activating the weak anion exchange resin with a weakly acidic metal complexing reagent, the weakly acidic metal complexing reagent partially disassociating into protons and metal complexing anions, whereby some functional groups in the weak anion exchange resin are protonated and bind with the metal complexing anions; and neutralizing a sample of the acidic solution with the activated weak anion exchange resin.