Oral Presentation Royal Australian Chemical Institute National Congress 2026

Chemical signatures of resistance: rapid phenotypic AMR detection by vibrational spectroscopy.    (136745)

Kamila Kochan 1 2 , Aaron McLean 1 2 , Divyansh Bangia 1 2 , Ava Rossetti 1 2 , Xenia Kostoulias 2 3 4 , Isabelle Magnin-Bougma 5 , Jeremy J Barr 2 5 , Anton Y Peleg 2 3 4
  1. School of Chemistry, Monash University, Clayton, Victoria, Australia
  2. Centre to Impact AMR, Monash University, Clayton, Victoria, Australia
  3. Infection Program, Department of Microbiology, Monash University, Clayton, Victoria, Australia
  4. Department of Infectious Diseases, The Alfred Hospital and School of Translational Medicine, Monash University, Melbourne, Victoria, Australia
  5. School of Biological Sciences, Monash University, Clayton, Victoria, Australia

Antimicrobial resistance (AMR) is one of the most pressing global health challenges, threatening the effectiveness of modern medicine. A key contributor to the AMR crisis is the lack of rapid and reliable diagnostic tools to guide antimicrobial therapy.1 Conventional antimicrobial susceptibility testing (AST) relies on detecting bacterial growth inhibition and typically requires 24–72 hours, leading to delayed targeted treatment and widespread empirical use of broad-spectrum antibiotics.2 

Vibrational spectroscopy offers a powerful, label-free and non-destructive alternative by probing the chemical composition of bacterial cells through their molecular vibrations.3-5 Each bacterium exhibits a characteristic spectral fingerprint that reflects its biochemical state and dynamic response to external stressors. Here, we present a rapid spectroscopic approach for phenotypic AMR diagnostics based on detecting early-stage chemical changes in bacteria following antibiotic exposure.4 By monitoring these molecular responses within a two-hour timeframe, the method enables clear discrimination between effective and ineffective drug treatments, allowing functional determination of antimicrobial susceptibility without reliance on prolonged growth measurements.

This strategy has been successfully demonstrated across several global priority pathogens, including methicillin-resistant Staphylococcus aureus (MRSA),4 vancomycin-resistant Enterococcus (VRE),5 and carbapenem-resistant Pseudomonas aeruginosa. Furthermore, we extend this approach to assess bacteriophage efficacy by identifying spectral signatures associated with productive phage–bacteria interactions, providing a novel platform for evaluating phage activity and supporting the development of personalised phage therapies.

Overall, this work establishes vibrational spectroscopy as a promising next-generation diagnostic technology capable of delivering rapid, phenotypic insight into antimicrobial and phage effectiveness, with significant potential impact on personalised infection management and global AMR mitigation.

  1. Murray, C.J., Ikuta, K.S., Sharara, F., Swetschinski, L., Aguilar, G.R., Gray, A., Han, C., Bisignano, C., Rao, P., Wool, E. Johnson, S.C., et al. 2022. Global burden of bacterial antimicrobial resistance in 2019: a systematic analysis. The lancet, 399(10325), pp.629-655.
  2. Ramzan, M., Raza, A., un Nisa, Z., Abdel-Massih, R.M., Al Bakain, R., Cabrerizo, F.M., Cruz, T.E.D., Aziz, R.K. and Musharraf, S.G., 2024. Detection of antimicrobial resistance (AMR) and antimicrobial susceptibility testing (AST) using advanced spectroscopic techniques: A review. TrAC Trends in Analytical Chemistry, 172, p.117562.
  3. Baker, M.J., Byrne, H.J., Chalmers, J., Gardner, P., Goodacre, R., Henderson, A., Kazarian, S.G., Martin, F.L., Moger, J., Stone, N. and Sulé-Suso, J., 2018. Clinical applications of infrared and Raman spectroscopy: state of play and future challenges. Analyst, 143(8), pp.1735-1757.
  4. Kochan, K., Jiang, J.H., Kostoulias, X., Lai, E., Richardson, Z., Pebotuwa, S., Heraud, P., Wood, B.R. and Peleg, A.Y., 2025. Fast and Accurate Prediction of Antibiotic Susceptibility in Clinical Methicillin-Resistant S. aureus Isolates Using ATR-FTIR Spectroscopy: A Model Validation Study. Analytical Chemistry, 97(11), pp.6041-6048.
  5. Rossetti A., Kostoulias X., Giergiel M., Jiang J-H, Peleg A.Y. and Kochan K., 2026.Vibrational spectroscopy for rapid profiling of vancomycin susceptibility in Enterococci. Analyst. DOI: 10.1039/D5AN01068C