Bioelectrochemical sensor to detect antibiotic-resistant pathogens project

NU SEDS Associate professor of the Department of Chemical and Materials Engineering Enrico Marsili is building a strong research group on Biofilms and microbial electrophysiology. In the last two years, he has built a well-equipped laboratory for bioelectrochemistry and medical biofilms. At NU, the researchers are developing novel bioelectrochemical sensors that rely on the principles of electrophysiology to detect specific pathogens and to characterize the biofilm they form. Further, Professor is engaged in a fruitful collaboration with the national oil industry to develop biofilm-based methods for enhanced oil recovery. The researchers are now modifying an environmental microorganism, P. putida, to overproduce biosurfactants that accumulate at the oil/water interface, thus increasing oil extraction in the production water. The professor has ongoing collaborative projects with the University of Belgrade, Serbia, Biomedical Campus, Rome, Italy, and Kyoto Institute of Technology, Japan.

Now the professor is working on Bioelectrochemical sensor to detect antibiotic-resistant pathogens project. Pseudomonas aeruginosa (PA) is a ubiquitous opportunistic pathogen, which is a major cause of infection and mortality for patients affected by chronic illnesses.

Therapy is particularly challenging because PA form biofilms, whose polymeric matrix, composed by polysaccharides, proteins, nucleic acids and lipids makes it inherently resistant to antimicrobial and antibiotics. Inappropriate therapy readily selects multi-drug resistant strains, which results in extremely poor prognosis. Therefore, prompt diagnosis and therapy are paramount to improve patients’ survival rate.

Generally, the diagnosis and the antibiotic sensitivity spectrum are available to clinicians 2 to 5 days after the specimen is sent for analysis. Bioelectrochemical detection of antibiotic-resistant strains is quantitative, can be extremely sensitive, with a detection limit of few hundreds cells/mL, thus allowing faster diagnosis and appropriate therapy decision and ultimately improving patient’s prognosis. In this project, researchers propose a novel bioelectrochemical approach for detection of antibiotic-resistant PA strains based on the variations (quenching or enhancement) of current output in active PA cultures exposed to oxidative electrode potential, following short-term exposure to several antibiotics commonly used in clinical practice.