| abstract |
A test carrier for the analytical determination of a component of a liquid sample, especially for the diagnosis of diseases, by means of a reaction sequence taking place on the test carrier with several test layers, which, in the initial state, are dry and, in the case of using the sample liquid, are wetted, comprising a base layer on which are present next to one another a sample application region and an evaluation region, a liquid transport path which extends from the sample application region into the evaluation region and a color-forming layer in which, on the basis of a color-formation reaction with the help of a color-forming reagent system, at least one color-forming reagent of which is present in the color-forming layer, there takes place an optically detectable change characteristic for the component to be determined. In the evaluation region above the surface of the color-forming layer facing away from the base layer, there is arranged an absorbent covering layer which, in the initial state of the test carrier, is so non-transparent that the color of the color-forming layer is not visible. The covering layer is in fluid contact with the liquid transport path and the covering layer and the color-forming layer are formed in such a manner that the color of the color-forming reagent becomes visible when both layers are wetted by the sample liquid. |