Detection of bacterial deposits and bioaerosols by Time-REesolved Laser-Induced Breakdown Spectroscopy (TRELIBS)

Potentialities of Time-REsolved Laser-Induced Breakdown Spectroscopy technique (TRELIBS or LIBS method) are investigated in order to detect biological matter in bulk and aerosolized forms. Alert detection of biological weapons is the main purpose. With this aim in view, eight different species in bulk form have been primarily considered: six bacteria and two pollens under a pellet form. A cumulative intensity ratio is proposed as a quantitative criterion due to its linearity and reproducibility. TRELIBS exhibits a good ability to differentiate between all these species whatever the growing medium, the specie or the strain. Studies are also extended to the analysis of aerosolized models with generated dry particulate matter and micrometric droplets to simulate single bacterial elemental compositions and concentrations. The expected capabilities make TRELIBS a potential candidate to trigger alarms either on surfaces or in ambient air.