Multizone element and method for analysis of whole blood

Claim 2

A multizone element for the assay or detection of an analyte in whole blood, the element comprising a support having thereon, in order and in fluid contact, a registration zone and a reagent/spreading zone, the reagent/spreading zone having a void volume and average pore size effective to accommodate whole blood, and containing an interactive composition for the analyte comprising a substance having peroxidative activity, the element characterized in that a whole blood cell filter zone is excluded, and the interactive composition is capable of providing, upon interaction with the analyte, a dye which can be spectrophotometrically detected at a wavelength greater than or equal to 600 nm.

Claim 3

The element as claimed in claim 1 wherein the void volume of the reagent/spreading zone is from 25 to 80 percent and the average pore size is at least 5 micrometers.

Claim 4

The element as claimed in either claim 1 or 2 wherein the reagent/spreading zone comprises a particulate structure comprising a plurality of particles non-swellable in and impermeable to whole blood, the particles having a particle size of from 1 to 200 micrometers and being bonded on surface areas of adjacent particles where those particles are in closest proximity to form a coherent, three-dimensional lattice which is non-swellable in whole blood.

Claim 5

The element as claimed in claim 3 wherein the particles comprise an addition polymer formed from one or more of the following ethylenically unsaturated polymerizable monomers: (a) up to 100 weight percent of an amino-substituent-free vinyl carbocyclic aromatic, (b) up to 25 weight percent of an acrylic acid ester, (c) up to 100 weight percent of a methacrylic acid ester, (d) up to 30 weight percent of an ethylenically unsaturated carboxylic acid, (e) up to 75 weight percent of an ethylenically unsaturated nitrile, (f) up to 20 weight percent of an amino-substituted vinyl carbocyclic aromatic, (g) up to 20 weight percent of an ethylenically unsaturated crosslinkable monomer, (h) up to 20 weight percent of a tertiary aminoalkyl acrylate or methacrylate, (i) up to 100 weight percent of a N-heterocyclic vinyl monomer, and (j) up to 20 weight percent of an acrylamide or methacrylamide, and the particles are bonded with an adhesive comprising an addition polymer formed from a blend of ethylenically unsaturated polymerizable monomers selected from the following group: A. a blend containing from 1 to 35 weight percent of one or more amino-substituent-free vinyl carbocyclic aromatics and from 65 to 99 weight percent of one or more alkyl acrylates or methacrylates, B. a blend containing from 20 to 95 weight percent of one or more amino-substituent-free vinyl carbocyclic aromatics, acrylic or methacrylic acid esters and ethylenically unsaturated polymerizable crosslinkable monomers, and from 5 to 80 weight percent of one or more ethylenically unsaturated polymerizable monomers having an active hydrogen or salts thereof, and C. a blend containing from 15 to 100 weight percent of one or more ethylenically unsaturated monomers selected from the group consisting of 1-vinylimidazole, vinylbenzyl alcohol, ethyl acrylate or an acrylamide or methacrylamide, and up to 85 weight percent of one or more ethylenically unsaturated polymerizable crosslinkable monomers.

Claim 6

The element as claimed in any of claims 1 to 4 comprising an interactive composition for the determination of glucose.

Claim 7

The element as claimed in any of claims 1 to 5 wherein the interactive composition comprises peroxidase, 4-aminoantipyrine and a buffer which maintains the pH at from 4 to 7 under conditions of use.

Claim 8

The element as claimed in any of claims 1 to 6 wherein the interactive composition comprises a color-forming coupler.

Claim 10

The method as claimed in claim 8 for the assay or detection of glucose.

Claim 11

The method as claimed in claim 8 for the assay or detection of cholesterol.