Facing the emergence of multi-drug-resistant bacteria, rapid and sensitive detection of the antimicrobial resistant genes in such organisms is crucial for appropriate and timely treatment management. In this work, a team from C2N has fabricated a microfluidic DNA biosensor immobilized with 6-mercaptohexanol and probe DNA sequence, aimed for the detection of antibiotic-resistant genes in Escherichia coli (E. coli). As proof-of-concept, the team has demonstrated the successful electrochemical detection of the target DNA sequence down to 10 fM in the presence of diluted lysed E. coli cells, by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). A new approach was used to analyze the CV and EIS plots based on the influence of non-linear mass transport phenomenon more representative of the surface modification under flow conditions in microchannel. The custom fitting of the model allows us to estimate the apparent charge transfer resistance and thus evaluate the surface coverage and surface molecular immobilization on the electrode. This approach represents a major advance not only for the early detection of sepsis but can be applied to a wide range of bioelectrochemical detection applications in complex sample matrices.
Références
Hiu Mun Man1, Choayb Omar1, Martina Freisa1, David Bouville1, Téo Baptiste1, Anne-Marie Haghiri-Gosnet1, Hervé Jacquier2,3, Isabelle Le Potier1, and Jean Gamby1
Microfluidics-Based Electrochemical Detection of Antimicrobial-Resistant DNA Sequence in Lysed Escherichia coli Medium.
ACS Electrochem. 2025, 1, 6, 886–896.
DOI https://doi.org/10.1021/acselectrochem.4c00203
Affiliations
1 C2N, CNRS, Université PARIS-SACLAY, Université Paris Cité
2 Unité de bactériologie, APHP Henri Mondor, Créteil
3 EA 7380 DYNAMIC, Université Paris-Est Créteil, Créteil
Key Words : Escherichia coli, sepsis, DNA biosensor, 6-mercaptohexanol, microfluidics, antimicrobial resistance
Figure : Antimicrobial resistance gene sequence detection by coupling microfluidics and on-chip electrochemistry
