A team from the Fraunhofer Institute for Cell Therapy and Immunology, Branch Bioanalytics and Bioprocesses are working with the German microbiology and food analysis laboratory Selektis LLC as part of a ProFIT project running from 2018 to 2020.
Core technology of the detection system is DNA-based amplification. Project partners have reduced the enrichment process from 18 hours to between four and six hours.
Traditional microbiological techniques can take up to four days, which is a problem for some food manufacturers who don’t want to wait that long for results before shipping goods. If a problem is then found the company may have to make a costly product recall.
Therefore, it is important to get a high concentration of Salmonella DNA in a short timeframe for sensitive detection. The researchers use fluorescent dyes to label the replicated DNA and detect it using capture molecules. Although molecular biological detection techniques are already in laboratories, they are rarely used in fully automated processes and not in food diagnostics.
The device could look like this:
Dr. Harald Peter said they have created a rapid culture with growth conditions optimized for Salmonella: “By means of an innovative, optimized enrichment method, we are able to increase the concentration of the bacteria to such an extent that we can detect them using molecular biological methods after only a few hours,” he said.
“To do this, the DNA of the salmonellae is amplified and automatically detected, something we achieve by extracting the DNA of the salmonellae and amplifying them by molecular biological means to such an extent that they can be detected after a further 30 minutes. For the rapid test, we design the molecules that specifically detect the DNA of the salmonellae.”