Rapid Raman spectroscopy-based test for antimicrobial resistance

Antimicrobial resistance is one of the top global health threats. In 2019, antimicrobial resistance was associated with 4.95 million deaths, of which 1.97 million were caused by drug resistant infections directly. The main subset of AMR is the antibiotic resistance, that is resistance of bacteria to antibiotic treatment. Traditional and most commonly used antibiotic susceptibility tests are based on detection of bacterial growth and its inhibition in the presence of an antimicrobial. These tests typically take over 1-2 days to perform, so empirical therapy schemes are often administered before the proper testing. Rapid tests for antimicrobial resistance are necessary to optimize the treatment of bacterial infection. Here we combine MTT test with Raman spectroscopy to provide 1.5-hour long test for minimal inhibitory concentrations determination. Several E . coli and K . pneumoniae strains were tested with three types antibiotics, including ampicillin from penicillin family, kanamycin from aminoglycoside family and levofloxacin from fluoroquinolone family. The test provided the same minimal inhibitory concentrations as traditional Etest confirming its robustness.