Dangerous antibiotic in milk: scientists have found a way to quickly detect it

Tomsk scientists make breakthrough: new method for detecting antibiotics in milk using fluorescence

Researchers at Tomsk State University have developed an innovative method for detecting the antibiotic sulfaguanidine in milk whey using the fluorescence effect. Scientists discovered unique fluorescent properties of this substance, which significantly simplifies its detection, as reported to "Gazeta.Ru" by the Ministry of Education and Science of the Russian Federation.

Sulfaguanidine is widely used as an antimicrobial agent in treating infectious diseases in farm animals, including cows. Often, producers exceed the permissible doses of the antibiotic, causing it to enter the milk. However, determining the content of this substance in dairy products presents a serious problem, as milk components can distort analysis results.

Thanks to the antibiotic's own intense fluorescence, researchers proposed using spectral and fluorescent methods for its accurate measurement.

"Traditional methods for detecting sulfaguanidine residues in food products (such as test strips or biosensors), which are commercially available and widely used, sometimes give false positive results. To develop a new measurement method, we decided to turn to spectrophotofluorimetric methods. Fluorimetric methods usually have high sensitivity, allowing for the detection and determination of very low concentrations of a substance, and optical spectroscopy is an ideal method for non-destructive sampling and real-time analysis. Also, these methods do not require the use of expensive reagents and equipment," Olga Chaikovskaya, professor of the Department of Optics and Spectroscopy at TSU Faculty of Physics and head of the LFFM TSU, told "Gazeta.Ru".

Experiments were conducted on whey from commercial milk of three popular brands - "Domik v Derevne," "Prostokvashino," and "Irbitskoe." Scientists added sulfaguanidine to the milk in a known concentration and then measured its content in the milk whey. For fluorescence and absorption analysis, a spectrofluorimeter and spectrophotometer were used, as well as special probes - bromocresol purple and methylene blue, which enhanced the signal and increased the method's sensitivity.

The most effective method for determining the antibiotic content in milk whey was fluorescence using a bromocresol purple probe, providing maximum sensitivity.

In the near future, Tomsk scientists plan to develop a portable device based on spectrophotofluorimetric methods for quick and convenient analysis of sulfaguanidine directly at the site of milk production or processing.