Eastman-kodak Company

Tai-Wing Wu

Glen M Dappen

David A Hilborn

Brent A Burdick

Sheryl S Sullivan

Shirley Y Lynn

Richard W Spayd

Mark W Bailey

Donald H Lo

Charles M Li Mutti

Shirley S Yau

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.

Method for extracting bilirubin-specific enzyme preparation

Disclosed herein is an assay useful for the quantitative determination of hemoglobin in whole blood. This assay utilizes a multizone element comprising a registration zone comprising particulate barium sulfate distributed in a 'blush' polymer, and a spreading zone having a void volume and an average pore size (e.g. greater than 5 microns) effective to accommodate whole blood. The element also contains an interactive composition capable of converting substantially all forms of hemoglobin into a detectable end product. One particularly useful interactive composition comprises a hemoglobin oxidizing agent (e.g. ferricyanide) and thiocyanate. Another useful interactive composition comprises an ionic surfactant, e.g. sodium octyl sulfate or sodium dodecyl sulfate.

Analytical element and its use in a whole blood hemoglobin assay

Bilirubin-specific enzyme preparation, assay compositions, analytical

A method and apparatus are described for the determination of an analyte in an aqueous liquid while eliminating the biasing effect of unknown interferents which are preformed or formed in situ during the determination. The method comprises physically contacting a sample of the liquid with an interactive composition for the analyte; measuring the spectrophotometric responses generated by such contact at a primary wavelength .lambda..sub.1 and one or more secondary wavelengths .lambda..sub.2, .lambda..sub.3, . . . .lambda..sub.n ; and determining analyte concentration or activity using the equation:

Method and apparatus for determination of an analyte and method of

A reagent composition, dry analytical element and a method of using same to determine total bilirubin in aqueous liquids are disclosed. The reagent composition comprises a diazonium salt, or reagents capable of producing a diazonium salt when contacted with water, and 3,3-dimethylglutaric acid or a salt thereof present in an amount effective to buffer the composition at a pH of about 3.5 or less when the composition is contacted with a 2 .mu.L sample of pooled human serum. The composition and elements described herein provide a means to eliminate the effect of an undetermined interferent which is either preformed or formed in situ in diazo-based total bilirubin determinations of biological fluids (e.g. uremic serum).

Reagent composition, dry element and method for determination of total

A direct, spectrophotometric method for determining the total bilirubin content of an aqueous liquid is provided by detecting the absorption spectrum of the aqueous liquid at a wavelength at which the absorption characteristics of unconjugated bilirubin and conjugated bilirubin are effectively identical. The method is carried out, for example, at a wavelength in the range of from about 385 to 425 nm. An interactive mordant for bilirubin is useful in the assay method to increase assay sensitivity. The assay can be performed as a solution assay or with a 'dry chemistry' test element, for example, a multilayer analytical test element.

Determination of total bilirubin

A method is described for the selective determination of the conjugated bilirubin (B.sub.c) or unconjugated bilirubin (B.sub.u), as well as the total bilirubin (B.sub.T), content of an aqueous liquid. The method comprises contacting the aqueous liquid with an analytical element having a dry reagent zone comprising an interactive mordant for bilirubin and thereafter detecting the absorption or emission spectra of the aqueous liquid at two or more wavelengths. The respective molar absorption or emission characteristics of B.sub.u and B.sub.c are predetermined for at least two of these wavelengths using a molecular weight of 584 for B.sub.u and a molecular weight in the range from about 750 to about 940 for B.sub.c. The B.sub.u, B.sub.c and/or B.sub.T content is determined from such spectra and absorption or emission characteristics. The interactive mordant for bilirubin is used to enhance the absorption characteristics or produce fluorescent emission of mordanted bilirubin.

Method for selective determination of conjugated and unconjugated

A method is described for the separation and isolation of conjugated and unconjugated bilirubin from an aqueous liquid containing one or both of the bilirubin components. The aqueous liquid is contacted together with an interactive mordant for bilirubin to mordant bilirubin, the mordanted bilirubin is separated from the aqueous liquid, and the mordanted bilirubin is treated in an aqueous medium with a chaotropic agent at least slightly soluble in the medium to release the conjugated and/or unconjugated bilirubin from the mordant. A preferred embodiment also provides for selectively separating conjugated bilirubin from unconjugated bilirubin by selectively solubilizing either the conjugated or unconjugated bilirubin released from the mordant. Isolated conjugated bilirubin is thereby obtained having a purity in excess of 75%. A reference composition comprising the isolated conjugated bilirubin is also disclosed.

Separation and isolation of conjugated and unconjugated bilirubin

An analytical element for the detection of two or more analytes in an aqueous liquid. The element contains an essentially dry matrix, at least a portion of the matrix containing at least two interactive compositions, a first composition generating a first radiometrically detectable species corresponding to the presence and/or concentration of one analyte, and a second composition for the inhibition or the destruction of a second radiometrically detectable species corresponding to the presence and/or concentration of one of the other analytes. The first and second interactive compositions are positioned in the element matrix to be in liquid contact with one another. Each of the first and second detectable species produced in the element is selected to have a different, characteristic, detectable absorption or emission peak in the electromagnetic spectrum.

Analytical element and method for analysis of multiple analytes

Analytical elements and methods for the detection of albumin in liquid samples feature an albumin-active complex comprising a detectable species bound to a carrier. The detectable species has a sufficiently high affinity for albumin that, when contacted with a liquid solution containing albumin, the detectable species separates from the albumin-active complex and becomes bound to albumin to form a complex comprising albumin and detectable species. The presence of albumin can be detected and, if desired, quantified by determining either the reduction of detectable species in the albumin-active complex of the formation of a complex comprising albumin and detectable species.

Element and assay for albumin

A fungal enzyme preparation has specific bilirubin degrading activity and, in a preferred embodiment, generates hydrogen peroxide. Extraction methods for the enzyme preparation are disclosed. Assay compositions, elements and methods using the aforementioned enzyme preparation are also disclosed.

Bilirubin-specific fungal enzyme preparation

Fluorimetric analysis of bilirubin contained in an aqueous liquid is carried out by the method comprising:

Fluorimetric analysis method for bilirubin

Ascorbic acid in a sample such as blood serum is quantitatively assayed by converting the ascorbic acid to dehydroascorbic acid with ascorbic acid oxidase and reacting the dehydroascorbic with a coupling substance such as phenylenediamine to produce a detectable product. The ascorbic acid oxidase and coupling substance can be combined to form a reagent composition which can be incorporated into integral multilayer elements to form a test element.

Ascorbic acid determination

Reduction of ascorbic acid interference in assays of aqueous fluids

A serum matrix or serum-derived composition which, after lyophilization and reconstitution, has a reduced optical density, evidencing improved homogeneity.

Growing community of inventors

Rochester, NY, United States of America

Tai-Wing Wu