Blood is by nature sterile and yet sepsis, which refers to the blood's contamination by infectious agents such as bacteria, is responsible for almost 20% of deaths worldwide.1 It currently takes 26 to 40 hours to identify a pathogen in a blood sample (transporting the blood sample to the laboratory, growing the culture in a Petri dish and analyzing it using mass spectrometry). This process slows down the administration of targeted antibiotic therapy.
CEA-Leti aims to reduce sample processing time so that it takes only 16 to 26 hours. In addition, this solution aims to do so using a low-tech approach: no reagents, no mass spectrometer and no trained technicians. Proof-of-concept tests on voluntarily infected healthy blood samples have shown that it is effective, reproducible and does not generate false positives or false negatives.
Four patents filed to protect this innovate solution
This technology is protected by four patents and should be much less expensive to implement. The solution consists of measuring potential differences in a 10ml sample of blood using 1mm-sized electrodes.
In its current form, the device has nine electrodes: one reference electrode and eight other electrodes that are each covered by a specific material. These electrodes provide a continuous measurement of an electrochemical profile that can be used to determine the type of bacteria present such as E. coli, staphylococcus aureus or streptococcus. If bacteria are present, they form a biofilm on the surface of the electrodes, which changes the physical properties of the electrodes and varies the potential difference measurements.
Today, the device is installed in a laboratory setup. Eventually, it will be portable: a blood culture bottle-like instrument placed inside a portable incubator. "We want a solution that meets the needs of isolated regions, tropical medicine, and even military operations or space missions," explains Pierre Marcoux, project coordinator. “The goal is to bring it to market around 2030."
A collaboration between the University Hospitals of Grenoble and Nice
The technology has been tested on voluntarily infected healthy blood samples. Its performance results include: 99.4% reliability for Gram type testing2 and 85% for gender identification. “We still have a lot of room for improvement," say Pierre Marcoux and Thibaut Babin, who developed the technology during his thesis. “In particular, the ANR project we are setting up with the Nice and Grenoble University Hospitals will enable us to conduct clinical studies. “
These studies will be used to create a database of healthy and infected blood samples that will improve the device's identification capabilities thanks to artificial learning. In parallel, a research project is being prepared with the Institute of Tropical Medicine in Antwerp, the Free University of Brussels and McGill University (Montreal) in order to conduct trials in Central Africa.