Improved Discrimination of Bacterial Spore Species With Ft-Ir Spectroscopy by Pretreatment With Autoclaving

Fourier transform infrared reflectance microspectroscopy was applied to the identification of bacterial endospores. Mid-infrared vibrational spectra were collected following minimal sample preparation from five species of bacterial endospores: Bacillus cereus, Bacillus globigii, Bacillus megaterium, Bacillus subtilis, and Clostridium perfringens. Discrimination among these species is enhanced when the endospores are autoclaved prior to data collection. This pre-measurement autoclaving technique is attractive by itself as it places the samples obtained, even false positives, into a safe state for handling. Speciation of these microorganisms can be accomplished by multivariate techniques such as principal component analysis (PCA) and soft independent method of class analogy (SIMCA).