Abstract: A heterogeneous, competitive binding immunoassay for either phenytoin or phenobarbital is conducted with a labeled conjugate comprising a derivative of hydantoin and a label. The hydantoin derivative is 5-ethyl,5-phenyl hydantoin and it is linked to the label (e.g. an enzyme) with a linkage derived from an aliphatic monocarboxylic acid. The immunoassay can be carried out either in solution or with a dry analytical element.

Abstract: Vesicles comprising a matrix of lipid membranes prepared from lipid materials are useful in biomedical studies and immunoassays. A labeled species is encapsulated within the vesicles and released when the vesicles are lysed with a surface active agent. The outer surface of the vesicles is essentially free of the labeled species. Immunoassays can be carried out in solution or with a dry analytical element.

Abstract: New substrates for .gamma.-glutamyltransferase (.gamma.-GT) are disclosed. These subtrates are useful in the colorimetric determination of .gamma.-GT since the cleavage of the .gamma.-glutamyl group produces a detectable species--an aminostyrylquinolinium dye. The substrates have the formula: ##STR1## wherein: R and R.sub.1 are independently selected from hydrogen, alkyl and alkoxy andQ is ##STR2## wherein: R.sub.2 is alkyl having from 1 to 4 carbon atoms;R.sub.3 and R.sub.4 are independently selected from hydrogen, alkyl, alkoxy, nitro, cyano and halogen; andX.sup..crclbar. is an anion.

Abstract: Esters and agents including the esters, useful as substrates for esterolytic and/or proteolytic enzymes, said esters being compounds of the general formula: ##STR1## in which R".sub.1, R".sub.2, R".sub.3 and R".sub.4, which may be the same or different, are hydrogen atoms or lower alkyl, lower alkoxy, alkylamino or dialkylamino radicals or in which two adjacent substituents can also represent a fused benzene ring, A is a residue of an amino acid or of a peptide and B is a nitrogen protective group conventional in peptide chemistry or derived therefrom and the method of preparation and use.

Abstract: The invention relates to a test strip for taking of daily blood sugar profiles, and also for glucose determination in urine for determining the individual kidney threshold of a diabetic as a daily profile, which finds use in glucose diagnosis.The objective of the invention is to stabilize the test strip in its function and to adapt it to customary measuring instruments, and this is achieved by attaching a film reaction membrane to a carrier, wherein the membrane was post treated with a complexing agent and an acyclic hydroxyamine or amino derivative.

Abstract: Certain substituted benzo- and naphthoquinone electron transfer agents are useful in analytical compositions, elements and methods, e.g. for determinations of living cells. These electron transfer agents are capable of being reduced by an analyte, and the reduced electron transfer agent, in turn, reduces another compound providing a detectable species (e.g. a dye). The reduction potential (E.sub.1/2) of the electron transfer agents useful inthis invention is in the range of from about -320 to about +400 mV as measured in an aqueous buffer solution at pH 7.

Abstract: A rapid method for the specific detection of the presence of Beta-lactamase from microbial sources is disclosed. The method utilizes a Beta-lactam ring containing substrate whose amide bond is hydrolyzed in the presence of Beta-Lactamase. A substrate, which includes a Beta-Lactam antibiotic with an acyl side chain containing an .alpha.-amino group and a .alpha.-phenyl group and/or its derivatives is first contacted with an organism thought to produce Beta-lactamase or a cell-free Beta-lactamase preparation, and, subsequently, it is determined whether the reaction product between the substrate and the organism or the preparation fluoresces.

Abstract: A method and device for determining the presence of an analyte in a sample suspected of containing the analyte is disclosed. The method involves contacting a test solution containing the sample and a first member of a specific binding pair with an end portion of a strip of bibulous material capable of being traversed by the test solution through capillary action. The first member of a specific binding pair is capable of binding the analyte. The strip contains a second member of a specific binding pair integral therewith for concentrating and non-diffusively binding the first sbp member at a small situs on the strip separated from the end portion of the strip. The detectible signal is produced in relation to the presence of the analyte in the test solution. The test solution passes through the situs as the test solution traverses the bibulous material.

Abstract: The present invention provides a method for assaying a biocomponent on the basis of an amount of bound peroxidase by the steps of supporting a biocomponent or a target substance containing a biocomponent on a gel-like carrier, developing the biocomponent or the target substance by electrophoresis, binding a receptor to the biocomponent or the target substance, binding peroxidase to the receptor, and determining the amount of the bound peroxidase, wherein hydrogen peroxide and 4-methoxy-1-naphthol are used as substrates.

Abstract: An analytical method for the determination of hydrogen peroxide utilizes a hydrazide or a hydrazine substituted with one or more electron withdrawing groups. The hydrazides or hydrazines react with phenolic color couplers in the presence of hydrogen peroxide and a peroxidative compound to form a dye detectable at a wavelength of 600 nm or greater. These materials can also be used to assay analytes, such as glucose and cholesterol, which can react to produce hydrogen peroxide.

Abstract: The present invention relates to a method for the detection and diagnosis of AIDS (acquired immune deficiency syndrome) ARC (AIDS Related Complex) and pre-AIDS conditions in body fluids by the use of a chemically synthesized peptide. The peptide has an amino acid sequence corresponding to a segment of the envelope protein, p41, of HTLV-III and has been found to be highly immunoreactive with antibodies in sera of patients with AIDS, ARC and pre-AIDS conditions. More specifically, the present invention is directed to the use of a chemically synthesized peptide containing therein a segment of about twenty-one (21) amino acids, or their analogues, in a prescribed sequence for the detection of antibodies to the HTLV-III virus in human body fluids of AIDS, ARC or pre-AIDS patients.

Abstract: A disposable test strip device for detecting and measuring ethanol in aqueous solutions is disclosed. The test strip includes an inert support pad that contains a stabilized dry form of the enzyme alcohol oxidase, a material having peroxidative activity and an oxygen acceptor that reacts with hydrogen peroxide to give a compound of changed color. The use of this strip to determine ethanol levels colorimetrically is also disclosed.

Abstract: An analytical element for the detection of hydrogen peroxide comprising a peroxidase-functional material, a hydrogen donor and a coupler, wherein the peroxidase-functional material and hydrogen donor are arranged so as to be separate from each other, for example in separate layers, but are made interactive by the application of a fluid sample.

Abstract: A multi-layered, chemical analysis material for analysis of an aqueous liquid, which comprises in one embodiment(a) a light-transmitting, water-impermeable support having provided thereon in sequence(b) a reagent layer and(c) a porous, sample-spreading layer, with(i) the reagent layer (b) containing a lake dye precursor dispersed in a hydrophilic binder,(ii) urease incorporated in the reagent layer (b) or in a layer adjacent the reagent layer (b), and(iii) a lake forming metal salt or lake forming metal oxide, which does not substantially inhibit the activity of urease, incorporated in the reagent layer (b) or in a layer adjacent the reagent layer (b) or a lake forming metal salt or oxide incorporated in a layer adjacent the reagent layer (b); and in a second embodiment the chemical analysis material includes(d) a radiation-blocking layer interposed between said reagent layer (b) and said porous, sample-spreading layer (c).

Abstract: There is disclosed a dry analytical element for .alpha.-amylase in a fluid sample which comprises the analytical element including a starch capable of forming a complex with iodine, an iodine compound and an oxidizing agent, and the iodine compound and the oxidizing agent are disposed in the element so that iodine may be liberated therefrom when the fluid sample is brought into contact with the analytical element.The analytical element of this invention enables an easy, prompt and accurate dry quantitative analysis of a component in a fluid sample, especially a biological fluid sample by the use of visible light with the aid of a spectrophotometer.

Abstract: A method of rapid determination of the isotype class for a panel of monoclonal antibodies is described. The assay comprises adsorbing on a solid support medium antibodies directed to specific immunoglobulin heavy and light chains. Once such isotype-specific antibodies are bound to the nitrocellulose paper, the treated strips can be incubated with the monoclonal antibody of interest. Upon formation of a complex between the specific iso-type antisera and the monoclonal antibody, the complex is visualized by reaction with a chromogenic substance. In the preferred embodiment of the invention, the treated nitrocellulose strips are stored in kit form. Using these prepared strips, the isotyping assay can be performed in less than two hours with a minimum of technical manipulation and expenditure of reagents.

Abstract: Apparatus for immunoassay of biological fluids, e.g. for AIDS antibodies, comprising an enclosed channel with fittings at the ends and a transparent top, together with a strip of nitrocellulose paper or other suitable material impregnated with antigens to the antibodies which are to be defected. The apparatus may have a single channel or it may have multiple channels.

Abstract: A novel imidazole derivative type reagent for analysis of hydrogen peroxide, a method of analysis of hydrogen peroxide using the same, a method of analysis of peroxidase using the same, and a multilayer chemicalanalytical element containing the same are disclosed.The imidazole derivative has the formula (I): ##STR1## wherein R.sup.1 and R.sup.2 represent an aryl group or a substituted aryl group, and R.sup.1 and R.sup.2 are identical with or different from each other, and R.sup.3 represents 2- or 3-pyrrolyl group, a substituted 2- or 3-pyrrolyl group, 2- or 3-indolyl group, or a substituted 2- or 3-indolyl group.

Abstract: There is described a dry chemistry test element consisting of a chemistry unit and a mount that is ammonia-sensitive, wherein the mount is improved to prevent ammonia carry-over from test element to test element. The improvement is based upon the discovery that in previous test elements which were joined together using ultrasonic bonding along energy-directing ribs, ammonia carry-over was created by the leakage of ammonia from one ammonia-sensitive element to another test element. Each element had a construction of a mount that provided a gas leakage path into the viewing aperture of the bottom sheet of the mount. The elements of the invention are provided with a smooth area on the bottom sheet which is fixed to the chemistry unit with an adhesive while the rest of the mount is joined at the energy-directing ribs.

Abstract: The device according to the invention intended for chemical analyses comprises a continuous sheet with at least two segments (6,8 or 30,31). The first one of the segments (6 or 30) contains a site (13 or 35) on which at least one of the reagents is present from the beginning and on which the contact between sample and reagent can take place. A second segment (8 or 31) contains a site (17 or 39) on which the presence of detectable substance can be shown. The first and other segments (6 and 8 or 30 and 31) are foldable in such a way that the site (13 or 35) with the reagent can be brought to overlap the site (17 or 39) for detection. The device also includes at least one arrangement (7 or 48) for the separation of reagent that has not reacted during the contact between sample and reagent. This arrangement is activated before the presence of detectable substance is shown. The segments are foldable in such a way that the desired segments can overlap each other for performing the desired analytical steps.

Abstract: Methods and kits are set out having improved selectivity and improved sensitivity for use in field and home immunoassays. A specifically binding biomaterial is attached to a macroextensive surface of a plastic strip or the like. A biological substance which is a specific binding partner to a binding site of the specifically binding biomaterial is attached to each of a plurality of synthetic particles. The particles are of a preselected size, refractive index, or the like to enhance their visibility in accordance with the Mie scattering phenomenon. Testing is by either contacting the particles with the strips to obtain adherence of the particles to the strips, or by exposing strips having the particles already adhering to them to a solution containing either the specifically binding biomaterial or the biological substance, whereby the particles adherence to the strip is eliminated. A quick and accurate pregnancy test is one result of the invention.

Abstract: The present invention provides a composition for assaying hydrogen peroxide having an enzyme, a buffer and a chromogen, wherein the chromogen is a sulfoalkyl derivative of a 3,3',5,5'-tetraalkylbenzidine or a water-soluble salt thereof represented by the following general formula I: ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 may be the same or different and each represent a straight-chain alkyl group having 1 to 6 carbon atoms, such as a methyl, ethyl, n-propyl, n-butyl, n-amyl or n-hexyl group. R.sub.5 and R.sub.6 each represent a hydrogen atom or a sulfoalkyl group of the following formula II:--(CH.sub.2).sub.n SO.sub.3 H (II)wherein n represents an integer of 1 to 6, with the proviso that either R.sub.5 and R.sub.6 represents a sulfoalkyl group and the sulfoalkyl group may be substituted with at least 1, preferably 1 to 2 hydroxyl groups. This composition has a high solubility in water and is usable over a wide pH range and for the preparation of both a test solution and a test piece.

Abstract: Stability of a sensitivity test disk obtained by impregnating a disk carrier with an aqueous solution of antibacterial agent and drying is improved by incorporating a water-soluble polymer material having film-forming properties in the disk carrier.

Abstract: Photometric apparatus, for counting the particulate components in blood and for determining the degree of particulate agglutination is disclosed. The apparatus comprises a body provided with an absorbent well for holding the blood bearing solution. The body is further provided with a passage to allow communication between the well and a detector which is capable of detecting the response of the particulate material to stimulating radiation. The absorptive well has the characteristic of absorbing radiation at the wavelength which characterizes the response of the particulate material to stimulating radiation. The well advantageously prevents the detector from detecting radiation that would otherwise be reflected by the well, whereby the linearity of the response of the apparatus is greatly increased. Linearity is further enhanced by assuring full crenation of the cells with a specific reagent.

Abstract: An improved process of performing analysis methods based upon biospecific affinity reactions in heterogeneous systems, wherein a ligand dissolved in a liquid is reacted with a receptor immobilized on a carrier, characterized by utilizing as the carrier a porous matrix in the form of a material body having an open capillary pore system capable of absorbing and retaining liquid phase and having such limited void dimensions that the total reaction rate of the biospecific reaction or reactions within the pore system between ligand and immobilized receptor will be at least substantially independent of the diffusion of the ligand in the liquid phase. A porous matrix for use in said process has the characteristics mentioned above.

Abstract: The present invention provides a process for the determination of glycerol in free or bound form by reaction with ATP in the presence of glycerol kinase (GK) and optionally of a hydrolase with the formation of glycerol-3-phosphate and ADP and determination of one of these reaction products with the help of at least one subsequent enzymatic reaction, wherein the determination is carried out kinetically and, for this purpose, the reaction with ATP is made rate-determining for the whole reaction and this is allowed to proceed according to the pseudo-first order in that there is added a sugar of the general formula: ##STR1## in which carbon atoms 2 and 3 have the D-threo configuration and R is a carbohydrate radical containing up to 3 carbon atoms and in which one hydroxyl group can also be replaced by a hydrogen atom.

Abstract: A method for preparing a blush polymer coating composition containing an immunologically reative species comprises milling the species and the other materials used in the composition to uniformly disperse the species therein. This coating composition can be used to prepare analytical elements for determining analytes (e.g. creating kinase-MB) whereby the effects of potential interferents are immunochemically removed. By milling the immunologically reactive species, e.g. antisera, into the coating composition, the resulting element has improved stability resulting in improved keeping in high humidity environments.

Abstract: An enzyme preparation having specific bilirubin degrading activity is described. The enzymes useful therein are obtained from various higher plant sources of the families Solanaceae, Musaceae and Liliaceae. Specific plant sources include eggplants, tomatoes and potatoes from the Solanaceae family, bananas from the Musaceae family, and onions from the Liliaceae family. Assay compositions, analytical elements and methods for use of such are also described.

Abstract: Ferric ion chelates are useful in analytical compositions, elements and methods for the determination of reductants, or other analytes which can produce a reductant. The ferric ion chelate is reduced to ferrous ion, which coordinates with a suitable ferrous ion coordinating ligand to form a colored complex. In particular, these compositions and elments are useful for detecting nicotinamide adenine dinucleotide, reduced form (NADH) or nicotinamide adenine dinucleotide phosphate, reduced form (NADPH), or an analyte (e.g. an enzyme) which produces NADH or NADPH in biological fluids.

Abstract: A method for testing skin for presence of moisturizing substances is provided which method includes the steps of applying to the skin a moisturizer formulation which includes protein, urea and/or glucose and/or other reducing sugar such as fructose all of which bind with water and form a film or coating on the skin which inhibits moisture loss from the skin, and subsequently testing the skin for the presence of protein, urea and/or glucose and/or other reducing sugar remaining on the skin which is directly correlated to the amount of moisturizer formulation remaining on the skin. When it is determined through the testing that there has been at least a predetermined loss of protein, urea and/or glucose or other reducing sugar, additional moisturizer is then applied to the skin.

Abstract: A method of manufacturing the test device and method of determining the presence and relative concentration of a component in a test sample. The device includes a carrier matrix incorporated with a reactant system capable of interacting with a sample component to produce a detectable response. For home use, the reactant system produces a visibly detectable response. The carrier matrix of the device comprises a new and improved whole blood compatible, glucose-permeable strip or layer of a polymerizable silicone material. A reactant system is homogeneously mixed into the polymerizable carrier matrix prior to complete curing of the matrix, and the matrix then is cured to hold the reactant system homogeneously throughout the carrier matrix in a known concentration while maintaining matrix penetrability of the predetermined component after complete curing of the carrier matrix.

Abstract: Reagent test devices are prepared in which reagent carrier matrices are separated from each other by hydrophobic barrier pads of identical height to the reagent carrier matrices such that liquid present in a reagent matrix material is retained therein and prevented from running over into another reagent matrix area present on the same test device.

Abstract: An analytical element is designed for the colorimetric determination of total cholesterol in aqueous liquids, such as biological fluids. This element comprises an absorbent material and critical amounts of cholesterol ester hydrolase (from about 1500 to about 12,000 I.U./m.sup.2) and a nonionic surfactant (from about 5 and up to, but less than 11 g/m.sup.2). The use of these ranges of reagents reduces the potential for interference by triglycerides present in a test sample. Total cholesterol is determined with this element by detection of a color change resulting from a series of enzymatic reactions which produce hydrogen peroxide.

Abstract: A method and device for separating blood into fluid and cellular fractions for diagnostic tests. The whole blood is introduced to a carrier containing a layer of carbohydrate which results in the rapid separation of the fluid from the cellular fractions. In a preferred embodiment, the device is fabricated in a sandwich design containing layers of carbohydrate and reagent material between two layers of plastic.

Abstract: Particular heterocyclic compounds are useful as color-forming couplers in analytical compositions, elements and methods. These compounds are represented by the structure: ##STR1## wherein R is a solubilizing group, R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are independently hydrogen, alkyl, alkoxy, aryl, aryloxy, a heterocyclic group, halo, amino or R, and Z represents the carbon atoms necessary to complete the nucleus of a 5- or 6-membered fused ring. The color-forming coupler is combined with an oxidizable color developing compound, e.g. 4-aminoantipyrine to provide a chromogenic composition. This composition can be used in solution or dry assays of biological fluids to produce a color dye in the presence of hydrogen peroxide or other analytes, e.g. glucose or uric acid, which react to produce hydrogen peroxide.

Abstract: A multilayer analytical element for analysis of analyte in a liquid sample comprising a liquid sample-spreading layer, a reagent layer containing a diazonium salt, and a liquid-impermeable light-transmissive support, being laminated in this order, in which said reagent layer contains a sulfonic acid group-containing polymer having at least 10 molar % of a repeating unit selected from those consisting of a sulfoalkyl group and sulfophenyl group. The analytical element can be an element comprising a porous reagent layer containing a diazonium salt and the liquid-impermeable light-transmissive support, being laminated in this order.

Abstract: A particular class of triarylmethane leuco dyes are useful in analytical compositions, elements and methods. These leuco dyes are triarylmethane compounds having an aromatic heterocyclic moiety attached to the central methane carbon and which, upon interaction with hydrogen peroxide, provide dyes having a maximum absorption at a wavelength equal to or greater than about 600 nm. Particularly useful leuco dyes have the structure: ##STR1## wherein R is a 5- to 15-membered aromatic heterocyclic moiety; and R' and R" are independently open chain or cyclic amines. These compounds are useful for providing detectable dyes in compositions and elements useful for detection of hydrogen peroxide or other analytes which react to produce hydrogen peroxide in aqueous liquids, e.g. biological fluids.

Abstract: A homogeneous specific binding assay device, a method for its preparation, and a method for its use in determining a ligand, such as antigen, hapten, or antibody, in, or the ligand binding capacity of, a liquid sample. The test device comprises a solid carrier member, such as a fibrous web matrix, e.g., paper, or a polymeric film or gel, incorporated with reagents for a homogeneous specific binding assay system which produces a detectable response, usually an electromagnetic radiation signal, that is a function of the presence or amount of the ligand in or the ligand binding capacity of the sample. Useful homogeneous specific binding assay systems include those involving enzyme substrate labels, enzyme prosthetic group labels, and enzyme labels. The detectable response preferably is a luminescent, fluorescent, spectrophotometric, or colorimetric response, which is measurable by visual observation or instrument means.

Abstract: A process for the production of a diagnostic device which is envisaged, in particular, for the detection of a pathologically increased concentration of dehydrogenases in fluids of humans, animals or plants and consists of a carrier and a substance mixture, in which, in each case with exclusion of UV radiation, the substance mixture, which has been adjusted to a pH value in the acid range, is brought into contact, in liquid form, with the carrier and the combination of carrier and substance mixture is subsequently dried and then enclosed in a packaging casing which is opaque to light of higher energy than red light. The process has the peculiarity that the dried combination of carrier and substance mixture in the packaging casing is securely sealed against entry of air and moisture. The device thus produced can be stored for a long time before use, without its ability to function being substantially changed.

Abstract: Viruses are detected by means of an immunoassay method in which an extended solid phase coated with antiviral antibody is employed to bind and remove virions from a specimen by forming an immuno-complex with antigens of said virions, a mobile solid phase comprising a dispersion of microspheres coated with the antiviral antibody is used to bind said microspheres to antigens associated with said immuno-complex, and the presence of bound microspheres is detected. The detection sensitivity is amplified by the ability to more readily detect the microspheres, which may be dyed or labelled. The extended solid phase advantageously may be in the form of a dipstick which can be easily contacted with the specimen. A virus detection kit provides the extended solid phase and mobile solid phases, each coated with antiviral antibodies.

Abstract: A composition for determining the presence of leukocytes, esterase or protease in a test sample. The composition comprises an ester having the structure ##STR1## in which: A is an N-blocked-amino acid residue or an N-blocked-peptide residue, X is O, S or NR', R is aryl, or lower alkyl, R* is H, or lower alkyl, and R' is H, lower alkyl or aryl; and a suitable buffer substance.

Abstract: An integral element for biological reaction comprising at least two layers consisting essentially of:a composite porous biological reaction layer comprising a fibrous material and a particulate material to which an active substance capable of participating in a biochemical reaction is fixed, anda porous layer of a fibrous material,in which:(1) the weight ratio between the particulate material and the fibrous material ranges from 1:20 to 1:0.3 on dry basis; and(2) the particulate material is contained in an amount ranging from 1 to 60 g/m.sup.2.

Abstract: A method for generating a series of digital responses to the presence of a given concentration of analyte in a test sample is described. The responses are obtained by providing varying levels of components of a competing reaction with constant levels of components of a control reaction. The pattern of digital responses permits a direct reading of the level of analyte in the test sample. Analytes may be either substrates for enzyme reactions, or may be, themselves, enzymes.

Abstract: A volume independent test device is formed in which the reagent matrix is covered by a water-impermeable coating or membrane. At least three openings extend through the coating or membrane material, penetrating into the underlying reagent matrix. These openings permit liquid to pass through the coating or membrane material and into the reagent matrix material until the reagent matrix becomes saturated.

Abstract: A composition and test device for determining the presence of an analyte selected from leukocytes, esterase and protease in a test sample. The composition comprises an ester capable of producing a detectable response upon interaction with said analyte, and a diazonium salt having the structure ##STR1## in which A.sup.- is an anion, and R same or differ, is H, lower alkyl, aryl, or both of R together form a fused ring system, and in which R' is H, OH or lower alkyl.

Abstract: Disclosed herein is an assay useful for the determination of an analyte in whole blood. In particular, this assay is useful for the quantitative determination of peroxide-generating analytes, such as glucose or cholesterol, in whole blood. This assay utilizes a multizone element consisting essentially of a support having thereon, in order and in fluid contact, a registration zone and a reagent/spreading zone. The reagent/spreading zone has a void volume and average pore size effective to accommodate whole blood, and contains an interactive composition necessary for the analysis. Such composition is capable of providing, upon interaction with the analyte, a dye which can be spectrophotometrically detected at a wavelength greater than about 600 nm.

Abstract: Disclosed herein is an apparatus and process for conducting immunoassays. The apparatus comprises a first member which is a membrane or a filter to which is bound an antibody, typically a monoclonal antibody, or which is capable of extracting cells from a fluid sample. The apparatus further comprises a second member which is composed of absorbent material which acts when in contact with the first member to induce flow through the first member when a fluid sample is added to it. The apparatus is used to conduct immunoassays by applying a sample to the upper surface of the first member to bind antigen in the sample by means of antibody fixed to the first member or, in certain cases, by extracting cellular material which has antigen associated with it. Addition of the sample is followed by addition of labeled antibody against the antigen being assayed followed by a washing step to remove unbound labeled antibody.

Abstract: Chemical analysis sheets comprising a reagent layer, a porous spreading layer and a cover layer provided with a small opening are disclosed. The cover layer prevents rapid evaporation of moisture to ensure a complete reaction between the chemical reagent and the ingredient tested for.

Abstract: A test system having an extended range of measurement and an appropriate procedure for the determination of NAD(P)H or of substrates or enzymes which react to form or consume NAD(P)H in fluids is provided. The test system contains, at one and the same time, several substances acting independently of one another as electron acceptors with respect to NAD(P)H and having different electrochemical potentials. Addition of the test system to the sample solution gives rise to different end products which can be analytically differentiated and which are evaluated visually or by other techniques of measurement.

Abstract: A method is provided for determining the concentration of pregnanediol glucuronide (PG) in a woman's urine which is characterized by utilization of the reagent 20.alpha.-hydroxy-4-pregnen-3-one (20-.alpha. reagent) in a form in which it reacts with antibodies binding to PG. The method is adaptable to a visual color indication test which can be performed by the woman herself as well as by laboratory analysis. The method can be used to define the period in which conception can occur, to define a post-ovulation safe period in which conception is prevented, and as an early pregnancy indicator.