Devices and formulations for detecting, screening and monitoring levels of certain constituents in bodily fluids and method

A method of making a device for conducting a non-invasive analysis of a bodily fluid to determine the presence and the level of a certain constituent carried by the bodily fluid, the device including an indicator formulation capable of changing color in response to exposure to the certain constituent in the presence of ambient air to provide a visible indication of the presence and the level of the certain constituent carried by the bodily fluid, the method comprising:

• providing a target area on a carrier substrate of a fibrous material having fibers and voids in a high void volume in juxtaposition with the target area and with fibers within the carrier substrate, with voids establishing communication between fibers and ambient air;
• wherein the carrier substrate has a total volume and the high void volume is within a range of about eight to twelve percent of the total volume;
• applying a chromagen formulation to fibers of the carrier substrate to create a chromagen-laden carrier member wherein applied chromagen formulation carried on fibers is placed in juxtaposition with voids in the carrier substrate for enabling exposure to ambient air within the voids;
• and
• subsequently applying to the chromagen formulation carried on fibers of the chromagen-laden carrier member a selected reagent having a particular constituent-specific formulation to combine the selected reagent with the chromagen formulation on fibers of the carrier member, thereby establishing the indicator formulation on fibers of the carrier member, in juxtaposition with voids within the carrier substrate and with the target area, in place for communication with ambient air within the voids and reception of a sample of the bodily fluid later placed upon the target area of the carrier substrate and in communication with ambient air within the voids for enabling reaction with the indicator formulation on the fibers, with the sample exposed to ambient air present in the juxtaposed voids as the certain constituent in the sample reacts with the indicator formulation.