Constant volume chemical analysis test device

DETAILED DESCRIPTION The present invention provides a test device for a bodily fluid comprising, in sequential contact, an absorbent layer, a barrier layer, and a reagent matrix layer having a defined saturation volume, wherein the absorbent and barrier layers each includes an opening for applying a test sample directly onto the reagent layer.
In one embodiment, a support is provided on a side of the reagent layer opposite the dosing surface.
In an especially preferred embodiment, the support layer includes an aperture which permits contact between the lower layer of the reagent matrix layer and the atmosphere.
In another embodiment, the reagent layer may be substantially enclosed, with the proviso that the barrier and absorbent layers include openings exposing a substantial portion of the reagent layer to the atmosphere.
In a preferred embodiment, the dosing surface of the reagent matrix layer constitutes a means for retaining cellular components.
One preferred embodiment comprises a test device and method for determining glucose in a whole blood sample.
Other preferred embodiments are test devices and methods for cholesterol and alcohol determination in whole blood samples.