Abstract: Newly synthesized chromogenic thiol-indicating benzoisothiazolone derivatives having the structure: ##STR1## where R.sup.1, R.sup.2 and R.sup.3 are as defined in the specification, are useful in the detection of thiols, particularly in an aqueous system. This process comprises contacting the aqueous system with a chromogenic thiol-indicating benzoisothiazolone derivative as described herein. Chromophoric changes due to thiol-mediated reduction of the benzothiazolone derivative then occur. Such changes can be in a solution or on an indicator surface in contact or having been in contact with the aqueous system. The chromophoric changes, due to a bathochromic shift in characteristic light absorption upon reduction of the benzoisothiazolone derivative, are proportional to the amount or rate of appearance of thiols in the aqueous system.

Abstract: Newly synthesized chromogenic thiol-indicating benzoisthiazolone derivatives having the structure: ##STR1## where R.sup.1, R.sup.2 and R.sup.3 are as defined in the specification, are useful in the detection of thiols, particularly in an aqueous system. This process comprises contacting the aqueous system with a chromogenic thiol-indicating benzoisothiazolone derivative as described herein. Chromophoric changes due to thiol-mediated reduction of the benzothiazolone derivative then occur. Such changes can be in a solution or on an indicator surface in contact or having been in contact with the aqueous system. The chromophoric changes, due to a bathochromic shift in characteristics light absorption upon reduction of the benzoisothiazolone derivative, are proportional to the amount or rate of appearance of thiols in the aqueous system.

Abstract: The present invention relates to a process for the production of porous, and particularly macroporous, membranes. The membranes produced by the process are highly absorbent and can therefore be employed, as supporting matrices for test strips. These test strips can be used for the detection of substances to be analyzed in a liquid.

Abstract: A test device and method of determining the presence and concentration of proteins, including albumin and Bence Jones proteins, in a test sample are disclosed. The test device includes a test pad comprising a new and improved carrier matrix incorporating an indicator reagent composition capable of interacting with proteins to produce a visually or instrumentally detectable and/or measurable response. The new and improved carrier matrix of the test pad comprises a fibrous, bibulous substrate, such as filter paper, homogeneously impregnated with a polymerized urethane-based compound dispersed in a liquid vehicle comprising an aprotic solvent and an alcohol. The resulting non-greening carrier matrix provides improved color resolution and increased sensitivity to proteins in dry phase test strip assays, thereby affording a more accurate and trustworthy protein assay of liquid test samples, such as urine.

Abstract: A light emitting diode with reduced stray light includes a base with an active light emitting element mounted in the base. An epoxy envelope is mounted on the base. The envelope includes a conical side portion and a spherical dome portion. The envelope is encapsulated with optically absorbing material of low reflectivity. The optically absorbing material is in direct contact with the side portion of the envelope and part of the spherical dome portion leaving an exposed portion through which rays of light pass.

Abstract: A new and improved method and apparatus are provided for non-invasive monitoring of changes in blood glucose concentration in a tissue specimen and particularly in an individual. The method uses acoustic velocity measurements for monitoring the effect of glucose concentration upon the density and adiabatic compressibility of the serum.In a preferred embodiment, the acoustic velocity measurements are made through the earlobe of a subject by means of an acoustic probe or monitor which includes a transducer for transmitting and receiving ultrasonic energy pulses to and from the blood flowing in the subject's earlobe and a reflector for facilitating reflection of the acoustic pulses from the blood. The probe is designed in such a way that when properly affixed to an ear, the transducer is positioned flush against the anterior portion of an earlobe while the reflector is positioned flush against the interior portion of the earlobe.

Abstract: A method and composition for the enzymatic assay of liquid test sample, such as urine or serum, for a specific analyte, such as glucose. The method utilizes a dry phase test strip comprising a carrier matrix impregnated with a stabilized enzyme reagent composition including an oxidase enzyme, such as glucose oxidase, that is capable of interacting with the analyte of interest; a chromogen that changes color in response to the analyte-oxidase enzyme interaction to reveal the presence and/or concentration of the analyte in the test sample; and a stabilizer, such as a hydrazide, like GIRARD'S Reagent T, or an amino acid, like arginine, or an amino acid derivative, like the tris(hydroxymethyl)aminomethane salt of glutamic acid, to improve the heat stability and shelf life of the dry phase test strip.

Abstract: The invention provides a nonenzymatic method useful for the semiquantitative determination of glucose, a test composition and test device. Glucose concentration in an aqueous test sample can be determined by preparing a test solution by contacting an aqueous test sample and a dihydroxide component, at an initial pH above 6.5, capable of forming a complex with glucose which complex formation releases a proton, and determining the final pH of the test solution. The invention also provides a self-indicating device format which allows the determination of glucose concentration by merely counting the number of pads which have changed color. No comparison to a color chart is required. The glucose test of the present invention is free of the interferences found in enzymatic glucose tests.

Abstract: The removal of excess fluid from a test strip should be performed in a consistent manner to provide consistent results. To eliminate user variability introduced by manual blotting techniques, the device of the present invention wipes fluid from a test strip as the test strip is passed beneath a blade. The one-piece device is made of plastic so that it may be manufactured inexpensively and disposed of after use. The wiping device can also be integrated with an end cap, so that the wiping device can be attached to the end of an instrument, such as a lancet. To obtain a blood sample, for instance, the user inserts a test strip into the wiping device, where it is held while the blood sample is taken. The user deposits the blood sample onto the test strip and pulls the test strip through the wiping device. The blade removes a portion of the blood sample to provide a consistent wiping action which is not influenced by user variability.

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: An inoculation device preferably for use in the testing of a fluid sample such as urine. The device includes a capillary flow system which allows for immediate and contemporaneous inoculation of a plurality of reagent pads forming part of a test substrate. The flow system includes a plurality of nozzles and a support structure which directs flow into the individual reagent pads while avoiding cross-contamination.

Abstract: A low-power programmable alarm clock system is provided for use with microprocessor-based reflectance photometer systems for generating an alarm control signal at pre-programmed alarm activation times. The system utilizes an alarm clock circuit which includes means for storing a count value corresponding to the number of predefined time periods existing between a given instantaneous time and a pre-programmed alarm activation time, means for generating a signal corresponding to the passage of each of said predefined time periods and using the generator signal to increment the stored count value each time the predefined time period has elapsed, and means for generating an alarm activation signal when the stored count value has been incremented to a predefined activation value.

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: 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 excape when fluid is drawn into the flow passage through a 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: A test device and method of determining the presence and concentration of proteins in a test sample are disclosed. The test device includes a test pad comprising a new and improved carrier matrix incorporating an indicator reagent composition capable of interacting with proteins to produce a detectable or measurable response. The new and improved carrier matrix of the test pad comprises a film, membrane or layer of a polymerized urethane-based compound, a water insoluble inorganic compound and an insoluble organic compound. The carrier matrix provides improved color resolution and increased sensitivity to proteins in dry phase test strip assays, thereby achieving an accurate and trustworthy protein assay of a liquid test sample, such as urine, having a protein concentration as low as about 5 mg/dL. Also disclosed is a method of making the test device.

Abstract: The present invention is directed to a reliable redox indicator composition for use in chemical assay systems and is particularly well suited for assay systems using a dry phase format. More specifically, the improved indicator composition of this invention is directed to the use of a divalent metal complex to prevent unwanted metal hydroperoxide mediated and similar-type oxidation of redox indicators. A fundamental element of the present invention involves the use of divalent metal complexes of the general formula: ##STR1## wherein M is either Zn(II), Co(II), Mn(II), or Rb(II).

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.