Identification of staphylococcal enterotoxin b in dairy products by immunochromatography with visual and digital video detection

Abstract

Detection of staphylococcal enterotoxins in food products is an important task of food poisoning prevention. The study was aimed to develop immunochromatography tests (ICTs) for detection of staphylococcal enterotoxins А (SEA) and be В (SEB), as well as to improve sensitivity of immunochromatography detection of staphylococcal enterotoxins (by the example of SEB) in dairy products relative to visual assessment by recording the analysis results with digital video recorders (DVR) using the principle of processing digital immunochromatogram images acquired using illumination in various spectral ranges. ICTs for detection of enterotoxins were designed as sandwich tests based on highly specific monoclonal antibodies (MABs) against staphylococcal enterotoxins. Milk, cream, sour cream, cheese artificially contaminated with SEB were analyzed. The analysis results were recorded visually or by DVR. DVR of immunochromatograms of the enterotoxin-containing dairy products acquired using illumination with white light in the wavelength range of 400–800 nm ensures a 4-fold increase in the SEB detection sensitivity, while that involving illumination with green light in the wavelength range having its maximum at 525 nm ensures a 4–8-fold increase relative to visual recording. The use of the “Reflecom” and “Zondazh” digital video immunochromatogram analyzers multiplies sensitivity of SEB detection by immunochromatography when assessing dairy products relative to visual recording.