Results on identification of bacteria aging in complex environmental samples using Raman spectroscopy

摘要

Spontaneous Raman scattering is a reliable technique for fast identification of single bacterial cells, when spectra areacquired in laboratory conditions where bacteria growth and state are controlled. We have developped a multi-modalsystem combining Raman spectroscopy and darkfield imaging, aiming at analysing environmental samples, typically inthe field context of biological pathogens detection. Such samples are heterogeneous, both in terms of phenotype contentand environmental matrix, even after a preliminary purification step. In this paper, we report a study on the identificationof Bacillus Thuriengensis (BT) mimicing pathogen bacteria, embedded in a real-world matrix: a sample of surface waterenriched with environmental bacterial species. The purpose is to evaluate both the detection limit of aging BT over timeand the false alarm rate, in the conditions of our experiment.