Abstract: Method for the determination of chlamydial or gram negative bacterial antigen comprising contacting a sample potentially containing extracted antigen with an optically active surface comprising an attachment layer, and a layer of non-specific protein.

Abstract: Reagent for determining the ionic strength and/or the specific weight of aqueous liquids and a reagent for this purpose, the composition of the reagent being such that the color change indicating the ionic strength is essentially directly dependent on the specific weight of the liquid to be determined and not on a pH shift.

Abstract: The predominant effect of pH change on multidrug resistance (MDR) independent of active drug efflux has been demonstrated in tumor cells through studies of the drugs doxorubicin and daunomycin. Specifically, the distribution of both drugs was monitored in fibroblasts and myeloma cells to examine the role of pH in drug partitioning. The invention comprises in one aspect the treatment of MDR by administering a therapeutically effective amount of a pH modulator. Diagnostic utilities are contemplated and extend to drug discovery assays and methods for measuring monitoring the status of the onset or development of pH-related conditions such as MDR, as well as the measurement of intracellular drug accumulation. Therapeutic compositions include a composition comprising a pH modulator alone or in combination with the dose-limited therapeutic agent(s), and a pharmaceutically acceptable excipient, are also contemplated.

Abstract: Disclosed is a method to evaluate the carcinogenicity of a compound using a transformation assay. The method includes contacting a compound to be tested for carcinogenicity with a test cell. The test cell has a defect in a protective cellular mechanism selected from the group of a defect in a DNA damage repair mechanism, a defect in cell cycle control, and a defect in the ability to prevent damage induced by oxygen free radicals. Cell growth is scored to identify the presence or absence of a transformation characteristic. The development of such a transformation characteristic indicates that the compound being tested is carcinogenic. Further embodiments include a method to identify tissue-specific carcinogens, a method to identify the biochemical mechanism of carcinogenicity of a compound, and a method to evaluate the anticarcinogenicity of a compound.

Abstract: The invention relates to a measurement apparatus (1) for analysing fluids, comprising a container (3) in the form of a syringe, into which a fluid may be taken in via an intake device (14) through at least one opening (5), and further comprising a sensor (7) which is either integrated in the container wall (9) or is attached to said container wall (9), the sensor(s) (7) being so disposed that it/they can come into contact with the fluid which may be taken up into the cavity (10).

Abstract: A cat litter which comprises a plurality of lightweight, resilient paper strips treated with a pH-indicator and/or an occult blood indicator and folded transversely into generally zig-zag shapes, enables early detection of feline urological syndrome. When wetted with alkaline urine secreted by the cat, the paper strips treated with pH indicator exhibit a noticeable color change. When wetted with cat urine containing occult or gross blood, the paper strips treated with occult blood indicator exhibit a noticeable color change. A mixture of pH indicator treated strips and occult blood indicator strips in the cat litter enables the detection of both alkaline pH and occult blood in the same urine sample. The color changes are easily visible to the observer without requiring unsanitary contact with the cat litter.

Abstract: A diagnostic sampling device and system for analyzing body fluids includes a transparent housing defining a test chamber therein in communication with a fluid inlet and a gas outlet, a test strip disposed in the test chamber and having an indicating portion reactive to a condition of the body fluids, and a ruler positionable outside the housing adjacent the test chamber for comparison with indicating portions of the test strip. A plug disposed in the gas outlet of the housing permits gas flow while preventing passage of body fluids, and is preferably formed of a porous material having a capacity to seal the gas outlet when contacted by body fluids. An absorbent filter is also disposed in the housing between the fluid inlet and the test chamber.

Abstract: In an automated analyzer containing a spectrophotometer for determining color changes in a urine sample the urine is admixed with a litmus, methyl red or azolitmin indicator effecting the color change, a surfactant and water. The spectrophotometer determines and prints whether a color change has occurred.

Abstract: A method for monitoring water quality including deriving calcium hardness and M alkalinity from the linear functional relation between calcium hardness and specific conductivity, and that between log value of M alkalinity and pH value, simplifying the temperature curve into a formula, and calculating directly the saturation index. A multipurpose and inexpensive automatic water quality monitoring apparatus that can be adapted for use in cooling towers, swimming pools, and boilers may be made from a combination of an conductivity meter, pH meter, and oxidation reduction potential meter commonly used in testing, and a simple algorithm of a central processing unit.

Abstract: A cat litter which comprises a plurality of lightweight, resilient paper strips treated with a pH-indicator and/or an occult blood indicator and folded transversely into generally zig-zag shapes, enables early detection of feline urological syndrome. When wetted with alkaline urine secreted by the cat, the paper strips treated with pH indicator exhibit a noticeable color change. When wetted with cat urine containing occult or gross blood, the paper strips treated with occult blood indicator exhibit a noticeable color change. A mixture of pH indicator treated strips and occult blood indicator strips in the cat litter enables the detection of both alkaline pH and occult blood in the same urine sample. The color changes are easily visible to the observer without requiring unsanitary contact with the cat litter.

Abstract: An apparatus is proposed making it possible in automated manner to perform several analyses on the same sample. For this purpose several fixed, chemical preparation cells (10) can separately receive several fractions of the same sample. Reagent injection systems (24) associated with these cells, as well as stirrers (14) make it possible to prepare, in each of them, a chemical preparation which is transferred into an analysis cell (36) associated therewith by an air ejector (44). The same ejector discharges the preparation to the drain (38) when the analysis has been completed. Ducts (70, 72), as well as a discharge line (62) then make it possible to wash, rinse and empty each chemical preparation cell (10).

Abstract: The invention relates to indicators for determine the proton concentration of strongly alkaline aqueous solutions which contain compounds of the formula (I) ##STR1## in which ##STR2##

Abstract: Methods and apparatus for monitoring and controlling pH, phosphate, and sodium to phosphate ratio in boiler systems operating with captive alkalinity chemistry are described. The methods for monitoring and controlling these parameters include the steps of determining the phosphate concentration via FIA, determining the pH, and using these values to determine the sodium to phosphate ratio. These values are then compared to the optimum values for the boiler system being treated; on the basis of this comparison, adjustments to the feed rate of water treatment chemicals being added to the system are then made. The apparatus includes a device for determining phosphate concentration via FIA, a device for determining pH, a means for determining sodium to phosphate ratio and a device for adjusting the feed rate of water treatment chemicals being added to the system. The device for adjusting the chemical feed rate is computer controlled.

Abstract: Combinations, called matrices with memories, of matrix materials with remotely addressable or remotely programmable recording devices that contain at least one data storage unit are provided. The matrix materials are those that are used in as supports in solid phase chemical and biochemical syntheses, immunoassays and hybridization reactions. The data storage units are preferably non-volatile antifuse memories. By virtue of this combination, molecules and biological particles, such as phage and viral particles and cells, that are in proximity or in physical contact with the matrix combination can be labeled by programming the memory with identifying information and can be identified by retrieving the stored information. Combinations of matrix materials, memories, and linked molecules and biological materials are also provided.

Abstract: The present invention is an improved method and related apparatus for quantitatively analyzing machine working fluids and other aqueous compositions such as wastewater which contain various mixtures of cationic, neutral, and/or anionic surfactants, soluble soaps, and the like. The method utilizes a single-phase, non-aqueous, reactive titration composition containing water insoluble bismuth nitrate dissolved in glycerol for the titration reactant. The chemical reaction of the bismuth ion and glycerol with the surfactant in the test solutions results in formation of micelles, changes in micelle size, and the formation of insoluble bismuth soaps. These soaps are quantified by physical and chemical changes in the aqueous test solution. Both classical potentiometric analysis and turbidity measurements have been used as sensing techniques to determine the quantity of surfactant present in test solutions.

Abstract: A single-phase method for quantitatively measuring the anionic surfactant content of an aqueous machining fluid is provided. The method is carried out at a pH value of from about 1.5 to about 3.0 and from about 9.5 to about 10.6 and involves the addition of an excess of a standardized aqueous solution of 1,3-didecyl-2-methylimidazolium chloride to the sample of aqueous machining fluid and then back titrating the excess 1,3-didecyl-2-methylimidazolium chloride with a standardized aqueous solution of polyvinylsulfuric acid potassium salt in the presence of toluidine blue indicator. Values of the amount of 1,3-didecyl-2-methylimidazolium chloride amount corresponding to anionic surfactant concentration are produced by conducting the method using a series of standard aqueous solutions containing anionic surfactant at known concentrations.

Abstract: An optical sensor is disclosed which uses a radioluminescent light source to supply the incident radiation for detecting a selected substance in a test medium. The radioluminescent source includes a beta emitting radio isotope which energizes a co-immobilized luminophore to release light in a given wavelength for a chemical sensor operation. The radioluminescent source is coupled with a sensing matrix for detecting and quantifying the analyte of interest. The sensing matrix produces a characteristic signal based on either absorbance or fluorescence which varies according to the concentration of the selected analyte in the sample. A photodetector measures the resulting optical signal from which the analyte concentration is determined.

Abstract: A process for measuring and controlling at an aim point the neutralization of an organic acid in an organic polymer solution using a near-infrared analyzer.

Abstract: An apparatus is described for carrying out solid phase microextraction and analysis of analytes in a fluid carrier in which a fiber within a housing is vibrated by a vibrating means during microextraction. The housing contains access means so that the carrier and analytes can be brought into contact with the vibrating fiber during the extraction stage. In a preferred embodiment of the present invention, the vibrating means comprises a membrane, a solenoid for vibrating the membrane, a frame, a retainer mounted on the frame for holding the solenoid, a holder for the membrane, and a retainer arm having one end connected to the retainer and the other end attached to the holder. A method for microextraction and analysis is also described in which a vibrating fiber is placed into contact with analytes to be analyzed in a suitable carrier deposited in a container for a sufficient period of time for microextraction to occur.

Abstract: There is disclosed an apparatus for the determination of a trace amount of an analyte substance or organism. A substrate solution is brought into contact with a small diameter tube which has captured, at least on its inner surface, a trace amount of an analyte substance or organism. The trace amount has the ability to change the pH of the substrate solution.

Abstract: A simultaneous dual excitation/single emission ratiometric method using fiber optic sensors is provided for detecting or measuring a parameter of interest in a sample, including pH, concentration of gases such as CO.sub.2, and the like. The method involves simultaneously providing modulated optical light corresponding to first and second regions of an indicator species' absorption or excitation spectrum, detecting modulated emission signals from the indicator species, demodulating the emission signals, calculating the apparent quantity of analyte present in the sample from the indicator emission signals and correcting the apparent quantity of analyte present for variations resulting from external factors, by determining the ratio of the demodulated indicator emission signals. An apparatus is provided for performing the method as well.

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

Abstract: Tests for elevated pH and volatile amines in aqueous fluids are disclosed, including tests useful in the diagnosis of bacterial vaginosis and in other biological conditions. By using formulated indicators and indicators held in matrices that are permeable to gas but not to liquid, the tests provide clear and sharp transitions detectable by visual or machine-readable means rather than by subjective judgments such as small gradations in color or olfactory determinations. The tests lend themselves readily to iconic readouts of the test indications and to the inclusion of positive and negative controls.

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: An apparatus and method for determining acid concentrations in solutions having acid concentrations of from about 0.1 Molar to about 16 Molar is disclosed. The apparatus includes a chamber for interrogation of the sample solution, a fiber optic light source for passing light transversely through the chamber, a fiber optic collector for receiving the collimated light after transmission through the chamber, a coating of an acid resistant polymeric composition upon at least one fiber end or lens, the polymeric composition in contact with the sample solution within the chamber and having a detectable response to acid concentrations within the range of from about 0.1 Molar to about 16 Molar, a measurer for the response of the polymeric composition in contact with the sample solution, and, a comparer of the measured response to predetermined standards whereby the acid molarity of the sample solution within the chamber can be determined.

Abstract: Safety apparel for use in harardous environments has an indicating material incorporated in the surface of the apparel. On exposure to hazardous materials, such as acids and bases, the surface changes color to indicate exposure and provide a warning. Further, a material and method is provided to treat surfaces to indicate exposure to hazardous materials. The treated surfaces may exhibit reversibility effective to indicate exposure over repetitive cycles.

Abstract: A method for determining pH or pCO.sub.2 using luminescent lifetimes and energy transfer in which an energy transfer donor-acceptor pair is exposed to a sample to be analyzed, the donor of the donor-acceptor pair being photoluminescent and the acceptor of the donor-acceptor pair being sensitive to the pH or pCO.sub.2 of the sample. One or both of the donor-acceptor pair may be bound to a carrier. The sample is irradiated and the resultant emission detected. By measuring the apparent luminescent lifetime, the pH or pCO.sub.2 of the sample can be determined.

Abstract: The method of continuously controlling pH of an acid scrubbing liquid includes continuously withdrawing a constant partial stream from the scrubbing liquid; continuously measuring a pH in the partial stream with a glass electrode; adding base at a first rate to the partial stream upstream of the glass electrode and continuing the adding until the measured pH is in a pH set-point range of from 2.5 to 11.5; after the pH is in the pH set-point range, changing the first rate of adding base to the constant partial stream to compensate any subsequently occurring pH deviations; during the changing of the first rate of base addition, measuring the first rate of base addition to obtain a measured first rate; and automatically controlling a pH of the acid scrubbing liquid using the measured first rate as a controlling parameter by selecting a rate set-point range of the first rate of adding base to the constant partial stream so that the measured pH can be brought into the pH set-point range of from 2.5 to 11.

Abstract: A method of determining the total carbon dioxide concentration in plasma (TCO.sub.2 plasma) directly from a whole blood sample involves adjusting total carbon dioxide concentration measured in the whole blood sample (TCO.sub.2 whole blood) using a volume dilution factor (VDF) to give a value that is equivalent to TCO.sub.2 plasma.

Abstract: Disclosed are a method and device for the determination of specific gravity in aqueous systems, particularly urine. The invention improves upon the known systems for detecting specific gravity by the use of a polyelectrolyte polymer and pH indicator by the addition of a crown ether ionophore which enhances the ability of the reagent system to indicate the fluid's specific gravity.

Abstract: A chloride analyzer includes an inlet valve and filters for process water to be analyzed, as well as a pH electrode to verify the pH value of the incoming liquid before further treatment. A stripper bubbles stripping air through the process water to remove hydrocarbons and hydrogen sulfide therefrom, and the discharge line from said stripper feeds a reaction vessel to which also reagent from a supply vessel is passed. After a suitable reaction time, optionally followed by a further air stripping operation through air supply line, the reaction products are fed via line to an ionometry measuring cell where chloride analysis is carried out using a specific ion selective electrode.

Abstract: A system and method in which a photoluminescent ligand is added to a sample to be analyzed in the form of a photoluminescent probe having intrinsic analyte-induced lifetime changes. The method preferably employs phase-modulation fluorometry to measure the lifetime changes. Specific probes are disclosed for measuring various analytes, particularly ionic solutes, including H.sup.+, Ca.sup.2+ and K.sup.+.

Abstract: The invention relates to colorimetric titration method, a titrator and colorimeter device. The titrating apparatus comprises radiant energy means for producing radiant energy. The device includes means for modulating an amplitude of an intensity of the radiant energy at a modulation frequency. The radiant energy is partially absorbed by an adjacent solution within a sample beaker having a color indicator dissolved therein. Radiant energy focusing means focuses the modulated radiant energy transmitted through the sample and beaker on radiant energy detection means. The radiant energy detection means produces a transmitted signal wherein an intensity of the transmitted signal is directly proportional to the intensity of transmitted energy. Filtering means filters the transmitted signal, such that a center frequency of the filtering means matches the modulation frequency of the radiant energy means.

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

Abstract: A reagent composition comprising (a) one or more pH buffers, (b) one or more pH indicators, and (c) one or more surfactants as a sensitizer, is suitable for measuring ionic strength or specific gravity of aqueous solution samples such as urine rapidly and precisely.

Abstract: An apparatus is provided for adjusting the pH of water in an aquarium. A measured sample of the aquarium's water is combined with a chemical indicator. The pH of the aquarium is then determined. If the pH is too low, drops of basic fluid having a known pH are added to the sample until the desired pH has been achieved. The number of drops of base added is then converted to an amount of a secondary base, based on the volume of water in the aquarium. This quantity of secondary base is then added to the aquarium and the pH is thereby adjusted to the desired level. Similarly, if the pH of the aquarium needs to be lowered, drops of acid are added to the sample and the number of drops of acid required to bring the sample to the correct pH is converted to a quantity of a secondary acid to be added to the aquarium to the lower the pH to the desired level.

Abstract: A method of determining the concentrations of at least two of plural kinds of known free acids and ions contained in a solution, wherein these known free acids and ions are known beforehand to be different from each other in temperature changes and conductivity changes which are to occur in response to a titrant. The method includes a step of generating a differential temperature curve and an electric conductivity curve, which are obtained from a thermometric titration and a conductometric titration respectively and are used complementarily so that an end point which is hardly ascertained by one method of titration may be ascertained by the other method.

Abstract: The invention pertains to a method for generating the fluorescence of polyanionic fluorophores in low dielectric media with fluorescence activation produced by specific quaternary onium compounds. The method may be used for measuring an analyte and may be useful in sensor devices.

Abstract: Biological indicators are provided for use in validating and routinely monitoring oxidizing gas sterilizations. The biological indicators are based on Bacillus circulans spores that are enclosed in packages with sufficient permeability to admit a sterilizing amount of vapor while being substantially bacteria impermeable.

Abstract: A device and process for increasing analyte concentration in a sorbent from a source of analytes contained in a sample uses means for increasing a temperature differential between the sample and the sorbent. The sorbent can be a polymeric coating on a substrate. The sorbent is located in a headspace of the sample and has internal cooling means such as liquid carbon dioxide so that the sorbent can be cooled relative to the sample. Preferably, the sample is heated to further increase the temperature differential between the sample and the sorbent. As the temperature differential increases, a partition coefficient of the sorbent/sample also increases. Preferably, the sorbent is located in a headspace of the sample. Previously, for certain analytes, the partition coefficient was too low and the concentration of analytes extracted into the sorbent from the sample was insufficient to provide an accurate measurement of concentration.

Abstract: In a device for determining the concentration of a reagent from a group consisting of gases with acid or alkaline reaction in aqueous environments, and volatile acids and bases in liquid or gaseous samples, a sample chamber is situated in a housing and a unit for pH measurement with a reaction space is separated from the sample chamber by an ion-impermeable, gas-permeable membrane. The feeding of the reaction space with buffer solution is facilitated by connecting the reaction space by means of an ion-permeable channel to a reservoir for a buffer solution located outside of the pH measuring unit.

Abstract: Organometallic compounds such as tricarbonyl-(.eta..sup.4 -1,3-cyclo-hexadiene)lron(O) display an infrared spectrum which varies according to the solvent polarity, pH and similar factors. By comparing the wavenumber position and shape of the peak of a test spectrum with reference spectra by interpolation or extrapolation, information is obtained about the test sample, even a quantitative analysis in some cases. More than one organometallic compound may be used in one experiment (for double checking), and/or a mixture of analytes may be investigated, for obtaining information about the combination.

Abstract: A device for monitoring the boron content of the borophosphosilicate, BPSG. The BPSG is obtained by the oxidation of silane, of diborane and of phosphine in a reactor, starting with a first, diborane/silane gas mixture and a second, phosphine/silane gas mixture by monitoring the ratio .rho.=diborane/(diborane+silane) of the mixture resulting from the mixing of the first and second gas mixtures. Monitoring of the boron content is obtained by measuring the density of the first mixture, determining the amount of residual hydrogen in the first mixture and modulating the mass flow rate of the first mixture in response to the calculated ratio .rho..

Abstract: A method for monitoring the boron content of the borophosphosilicate, BPSG. The BPSG is obtained by the oxidation of silane, of diborane and of phosphine in a reactor, starting with a first, diborane/silane gas mixture and a second, phosphine/silane gas mixture by monitoring the ratio .rho.=diborane/(diborane+silane) of the mixture resulting from the mixing of the first and second gas mixtures. Monitoring of the boron content is obtained by measuring the density of the first mixture, determining the amount of residual hydrogen in the first mixture and modulating the mass flow rate of the first mixture in response to the calculated ratio .rho..

Abstract: A target-specie responsive regulation of water treatment agent feed is achieved by the monitoring of a subject target-specie indicator. A target specie in a sample taken from the system is selected as the subject target-specie indicator, or instead an incipient reagent is added to the system sample to form a subject target-specie indicator. Such a formed subject target-specie indicator comprises a combination of the incipient reagent and a target specie. The subject target-specie indicator might then monitored by fluorescence analysis of the sample to determine at least one fluorescence emission value that can be correlated to the in-system concentration of the target specie. In combination with an inert tracer, the system consumption for the target specie can be determined. A responsive adjustment of the in-system concentration of a water treatment agent can be made.

Abstract: The present invention provides an optical fluorescence based sensor for measuring the concentration of a gas (e.g., CO.sub.2 or ammonia) in a medium such as blood which has improved drift stability. In a preferred embodiment, the sensors of the present invention comprise microcompartments of an aqueous phase having a pH sensitive sensing component within a hydrophobic barrier phase. The sensors of the present invention are substantially free of partitioning species other than the analyte of interest which can migrate from one phase to the other in response to a change in pH in the aqueous phase and which substantially affect the concentration dependent signal. In an alternative embodiment, the sensors of the present invention are constructed so as to retard the migration of partitioning species, thus reducing the initial rate of drift.

Abstract: In the method for the determination of water, the sample is admixed with a molar 1:1 adduct of sulphur dioxide with an amine having a pK.sub.A of more than 6, dissolved in an aprotic solvent, and is oxidized with iodine.

Abstract: The total alkalinity of an aqueous metalworking fluid is monitored and controlled by a continuous titration method that continuously supplies a stream of the metalworking fluid, at a known, controllable flow rate, to a flow through chamber having therein a static mixing element. Simultaneously and separately a stream of acid titrant, of known acid concentration is injected into the flow through chamber at a known controllable flow rate. The acid titrant and metalworking fluid mix and react in the chamber and the reacted metalworking fluid exiting the chamber passed over the tip of a pH electrode. The pH of the reacted metalworking fluid is continuously monitored and the output of the pH electrode used to adjust the flow of acid titrant to the chamber until an endpoint pH valve (typically a pH of 4) is reached.

Abstract: The invention pertains to a method for generating the fluorescence of polyanionic fluorophores in low dielectric media with fluorescence activation produced by specific quaternary onium compounds. The method may be used for measuring an analyte and may be useful in sensor devices.

Abstract: An automated process for controlling the rate chlorine dioxide made from sodium chlorate-chloride and sulfuric acid is generated. The process automatically adjusts the rate of chlorine dioxide production to the needs of the system treated with chlorine dioxide by controlling the feed of one or more of the reactants by means of a multiple feed-back loop system which provides adequate oxidative treatment while avoiding overfeed or underfeed conditions.