Disclosed is a test device for rapidly detecting the presence or absence of a gaseous or liquid analyte in a liquid sample and for holding the liquid sample, comprising an indicator dye applied to a solid substrate and, optionally, a holding element that differs from the substrate. The solid substrate is formed from a member made of sterile compressed fibers selected from among pure cellulose fibers, pure or mixed polyurethane hydrogel, poly(hydroxyethyl methacrylate), amino polymer, polyacrylate, silicone, epoxide, sol-gel glass or polyolefin fibers, and an indicator dye is covalently bonded on the substrate. The compressed member physically binds, especially absorbs, the liquid sample. Also disclosed is a method for the production of said test device.
