Rapid test for harmful microbes in kerosene for safer air traffic
Fraunhofer IZI-BB | Fuels such as kerosene or fuels such as diesel can be contaminated by fungi or bacteria. The microorganisms settle in the liquid itself, on the inner walls of tanks and pipes or in the fuel filters and feed on carbon atoms. Since the fungi and bacteria multiply well in this environment, they can form a streaky biofilm and clog fuel lines and filters. This is a problem especially in aviation.
In order to prevent engines from failing in extreme cases, airlines are already having kerosene tested for microbial infestation before refueling and the tanks of their jets. The International Air Transport Association (IATA) also recommends such tests at regular intervals. Depending on the risk of contamination – short distances, low altitude or even a warm and humid climate, for example, promote microbial growth – the inspections take place annually or monthly. So safety is guaranteed.
So far, however, the detection of the microbes has been time-consuming: samples have to be taken from the tanks and sent to a laboratory. The evaluation takes up to four days. “We wanted to develop an automated and mobile detection system with which untrained personnel can detect and quantify microorganisms in tank fillings on site within 30 minutes,” says Hans-Jörg Kunte from BAM. The microbiologist is an expert in material damage caused by microorganisms.
Together with the Fraunhofer Institute for Cell Therapy and Immunology – Bioanalytics and Bioprocesses Division (IZI-BB), Potsdam, and the company M2 Automation, Kunte and his team developed a rapid test based on the DNA analysis of harmful bacteria and fungi. Microbes are isolated from a sample, their cell membrane is enzymatically broken down, the DNA is purified, amplified and labeled with a fluorescent dye. Similar to the polymerase chain reaction test for the detection of SARS-CoV-2, the presence of microbes can be detected via a detector that reads fluorescent light. The new detection is faster and more robust than a PCR test: It takes no longer than 30 minutes, works even at fluctuating outside temperatures and includes a wider range of microbes than the previously common laboratory detections. BAM has now registered the innovative process with the European Patent Office.
At the same time, the team from Fraunhofer IZI-BB and BAM is already working on converting the detection into a handy and easy-to-use detection device and miniaturizing all components for this purpose. A prototype is to be developed for this purpose.
Such a device could be on the market by 2025. So far, there is no such rapid test worldwide. “Biofuels will become more important in the future – they are more sustainable, but are preferred by microbes as a food source. With our patented rapid test, we want to help ensure that fungi and bacteria in kerosene can be detected more quickly and comprehensively,” says Hans-Jörg Kunte.