Saliva pH analysis is an accessible and non-invasive clinical diagnostic method. It makes it possible to detect, at an early stage, in particular gastrointestinal diseases: gastritis, stomach ulcers, duodenitis, etc. The pH level also affects the teeth: even a slight increase in the acidity of saliva can cause or suggest dental caries or other periodontal diseases.
A sensor that measures the pH of human saliva
This sensor is a fluorophore – or fluorescent dye – which reacts to the smallest pH fluctuations (tenths) in biological fluids. The analysis is carried out using microdoses of the substance and a spectrometer, in which the substance is irradiated with a special lamp. pH data appears in 5-7 seconds. The first results of joint studies of saliva samples and the sensor, carried out by the team, are here confirmed as conclusive.
“Modern fluorometric pH sensors are based on small organic molecules. Typically, they are very sensitive and are able to detect the desired analyte at very low concentrations, down to nanoconcentrations. Our sensor is based on a new compound: We introduced a fluorinated fragment, which allowed us to obtain the photophysical and electrochemical properties that we needed”, explains the main author, Timofey Moseev, research engineer in the Department of Organic and Biomolecular Chemistry at UrFU.
The sensor has been designed to be non-toxic and environmentally friendly. To create it, the chemists used an atom-sparing synthesis method: no catalyst (nickel, copper, palladium) or additional reagents were needed.
This new chemosensor can be used not only to detect pH suggestive of IBDbut also to analyze water (acidity, presence of metals or toxins) or to trace intracellular processes by acting as a fluorescent probe: the compound can accumulate at a specific location in the cell and color a part specific to the cell and then be monitored during the various cellular processes; however, this application remains to be explored and optimized…