Patent · US Expired

Constant volume chemical analysis test device

US4994238A · kind A · utility

64Cited by
77References
5Claims
0Family size

Inventors

Key dates

Filing dateJun 9, 1988
Grant dateFeb 19, 1991
Priority date
Expiry dateJun 9, 2008

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC12Q1/54
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

The multilayer test devices of this invention comprise, in order, (a) an absorbent layer; (b) a waterproof barrier layer; and (c) a quickly absorbent reagent layer having a determinate volume. The absorbent and barrier layers each include an aperture functionally aligned for application of a test sample through the absorbent and barrier layers and onto the surface of the reagent layer. The reagent layer contains one or more reagents which produce a detectable species in the presence of an analyte. The reagent layer preferably comprises an asymmetrical filter, which localizes cellular components of the test sample at or near the surface of the filter, while facilitating saturation of the filter by non-cellular sample components. Preferred embodiments of the test devices include devices for testing glucose, alcohol, cholesterol, or other analytes in whole blood.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.