Abstract: The present invention provides a test carrier for the analysis of a sample liquid with a test layer which contains a ligand fixed to to carrier particles, which ligand reacts with a component of the sample liquid, the test layer having a three-dimensional open structure which is so porous that the sample liquid with the component can penetrate into it, the carrier particles being arranged in the layer in such a manner that the ligand, upon pentration of the sample liquid, comes into contact with the component of the sample, wherein the carrier particles consist of an inorganic material, on the surface of which reactive organic groups are covalently bound as coupling groups, and the ligand is covalently bound to the coupling groups. The present invention also provides processes for the production of such a test carrier and a method for using it.