A wipe for detecting the presence of an explosive substance is composed of an absorbent or adsorbent substrate and a chemical detection solution impregnated within the substrate. In one embodiment the chemical detection solution includes a combination of reagents operable, when contacted with a particular explosive substance to undergo a chemical reaction or a series of chemical reactions to produce a compound having a visible color. In another embodiment, the chemical detection solution includes a redox color indicating agent that is operable to exhibit a color change upon reacting with the explosive substance.

A composition, method and kit for quantifying the concentration of one peracid or the total concentration of two or more peracids in a water source are disclosed. In particular, an oxidation sensitive or peroxycarboxylic acid selective leuco dye is used to react only with one or more peroxycarboxylic acids in a water source but not with peroxide usually co-existing in the water source. Not only does the oxidation sensitive or peroxycarboxylic acid selective leuco dye react with peracid(s) but also the reaction generates a color species that can be used visually or through absorbance measurement to quantify the peracid concentration. The method disclosed here is not a titration method, it involves a simple mixing step. The kit or composition disclosed here does not utilize a catalyst, such as iodine.

The present application discloses a sensor for determining a measurand correlated with a concentration of at least one analyte belonging to the class of reactive oxygen species in a measuring fluid, the sensor including a sensor element having an indicator substance, wherein the indicator substance is oxidized into an oxidized form of the indicator substance by the at least one analyte, a means for generating a flow of current in the sensor element that causes a reduction of the oxidized form of the indicator substance and thereby regeneration of the indicator substance, an optical measuring sensor to detect measuring radiation influenced by the oxidized form of the indicator substance and to generate an electrical measuring signal using the influenced measuring radiation, and a sensor switch connected to the optical measuring sensor to receive the measuring signal and to ascertain a measured value of the measurand using the measuring signal.

A test kit is provided. The test kit includes a case including a plurality of reagent containers storing reagents, each reagent indicating the presence of a substance when the reagent comes into contact with that substance. The test kit further includes a collector including a collector body, and a plurality of swabs coupled to the collector body and configured to collect substances. The test kit is configured to test for a plurality of collected substances by causing the reagents stored in the plurality of reagent containers to contact at least one of the plurality of swabs, and the test kit is further configured to display results of the test.

A wipe for detecting the presence of an explosive substance is composed of an absorbent or adsorbent substrate and a chemical detection solution impregnated within the substrate. The chemical detection solution includes a redox color indicating agent that is operable to exhibit a color change upon reacting with the explosive substance.

A wipe for detecting the presence of an explosive substance is composed of an absorbent or adsorbent substrate and a chemical detection solution impregnated within the substrate. In one embodiment the chemical detection solution includes a combination of reagents operable, when contacted with a particular explosive substance to undergo a chemical reaction or a series of chemical reactions to produce a compound having a visible color. In another embodiment, the chemical detection solution includes a redox color indicating agent that is operable to exhibit a color change upon reacting with the explosive substance.

An apparatus and method for measuring hydrogen peroxide concentration in water to an accuracy of 0.1 ppm comprises a colorimetric assay method to determine hydrogen peroxide concentration. The assay is monitored spectophotometrically at a desired wavelength. Each sample is corrected relative to a control sample and hydrogen peroxide concentration determined with respect to a standard curve.

A test kit is provided. The test kit includes a case including a top including a plurality of indicator pads and a crushing plate rotatable between a first position and a second position, the crushing plate including a plurality of crushing ribs. The case further includes a bottom hingedly coupled to the top, the bottom including a plurality of reagent ampoules storing reagents. When the case is closed with the crushing plate in the second position, the plurality of crushing ribs crush the the plurality of reagent ampoules. The test kit further includes a collector including a collector body, a plurality of swabs extending through the collector body, a removable cover covering a first side of the collector body, and a collector handle coupled to the collector body, wherein the collector is nestable within the case.

Methods and systems are disclosed for analyzing and treating a fluid containing a peroxyacid and/or peroxide. A method of analyzing the fluid includes introducing into the fluid a decomposition agent that catalyzes decomposition of the peroxyacid and/or peroxide into decomposition products including oxygen, then directly or indirectly measuring an amount of oxygen produced after introduction of the decomposition agent, and determining an amount of the peroxyacid and/or peroxide present in the fluid. The amount of peroxyacid and/or peroxide in the fluid can also be monitored and controlled by further adjusting the amount of the peroxyacid and/or peroxide in the fluid based on the determined amount thereof. A system for performing the methods includes a decomposition agent infusion device for introducing the decomposition agent into a fluid sample, and a sensor for directly or indirectly measuring an amount of oxygen produced after introduction of the decomposition agent.

A sensing device for determining the presence of hydrogen peroxide is disclosed. The sensing device comprises a light guide having a distal portion terminating at a light guide tip and a proximal portion, wherein the light guide tip is proximal to a layer of Prussian blue (PB), which is pure (or essentially free of contaminants). The sensing device produces a fast linear response and is durable, due to the robustness and purity of the PB. The PB is chemically deposited proximal to, or on, the light guide tip using a single-source precursor technique. Methods of making and using the device also are disclosed herein.