UrFU chemists have developed a sensor that can determine the pH level of human saliva. This is a fluorophore with a strong and steady emission that detects even minor pH changes in biological fluids (tenths). Micro doses of the chemical are used in the analysis, as well as a spectrometer in which the substance is irradiated with a specific light (its lifetime is tens of thousands of hours). In 5–7 seconds, the pH data emerges.