Rapid Determination of Antibiotic Susceptibility by Stimulated Raman Scattering Imaging of D2O Metabolism

Rapid antibiotic susceptibility testing (AST) is urgently needed for treating infections with correct antibiotics and slowing down the emergence of antibiotic resistant bacteria. Current clinical methods reply on culture and take at least 16 h. Here, using P. aeruginosa, E. coli and S. aureus as models, we show that the AST can be finished in 10 minutes by stimulated Raman scattering (SRS) imaging of D2O metabolic activities. The metabolic incorporation of D2O, which is used for biomolecule synthesis, can be monitored in a single bacterium. Time lapse experiments show that the C-D vibrational signal can be observed in a single bacterium within 10 minutes culture in D2O medium. Since water is universally used for biosynthesis in bacteria, SRS imaging of D2O metabolism has the potential to be generalizable to different bacteria species.