AUTHOR COPY Biomedical Spectroscopy and Imaging 3 (2014) 29–39 29 DOI 10.3233/BSI-130060 IOS Press Application of FTIR and SERS spectroscopy in analysis and discrimination of bacteria and their interferents Aneta Bombalska a,∗ , Monika Mularczyk-Oliwa a , Bartlomiej Jankiewicz a , Bartosz Bartosewicz a , Magdalena Gajda-R ˛ aczka a , Miron Kaliszewski a , Maksymilian Wlodarski a , Miroslaw Kwa´ sny a , Krzysztof Kopczy´ nski a , Malgorzata Szpakowska b and El˙ zbieta A. Trafny b a Institute of Optoelectonics, Military University of Technology, Warsaw, Poland b Department of Microbiology, Military Institute ofHygiene and Epidemiology, Warsaw, Poland Abstract. In recent years, growing threat of terrorist attacks with use of chemical or biological warfare agents is observed. Biological agents, due to often delayed effects, higher lethality and more difficult detection and identification compared to chemical agents, are especially dangerous. Therefore, rapid detection and discrimination of dangerous biological materials has become a security aim of considerable importance. Various analytical methods, including FTIR spectroscopy combined with statistical analysis have been used to discriminate various bioagents and their background interferents. The applicability for this purpose of another spectroscopic technique, Surface Enhanced Raman Spectroscopy (SERS), has also been intensively investigated in recent years. In this work, the results of the application of FTIR technique performed in reflectance mode using Horizontal Attenuated Total Reflectance accessory (HATR) for discrimination of vegetative bacteria, bacterial spores and background interferents are discussed. Applied technique is shown to be capable of distinguishing between vegetative bacteria, bacterial spores and fungi against other biological specimens. In addition, the results of initial studies on application of plasmonic nanostructures for enhancement of Raman scattering signals of bacterial cells are discussed. Our studies have shown that it is possible to obtain Raman scattering signal from single bacterial cell in presence of single plasmonic nanostructure. Keywords: SERS, FTIR, fungi, bacteria, PCA, hierarchical cluster analysis 1. Background The terrorists attacks in the recent years as well as the recent use of chemical weapon in Syria have shown that threat of the non-conventional weapons use still exist. Opposite to nuclear weapon, biolog- ical weapons, “the poor man’s atomic bomb”, are rather cheap and easy to build using equipment and materials that are used extensively for a host of civilian purposes. Therefore, extremely important is pre- paredness in terms of detection and identification of agents used in the attack. Microbial contamination is also an important problem in medicine, in food and pharmaceutical industry, as well as in the biotech- nology. In these fields fast identification and discrimination between pathogenic and non-pathogenic microorganisms is crucial for proper treatment and safety procedures. Bacteria can be detected and * Corresponding author: Aneta Bombalska, Institute of Optoelectonics, Military University of Technology, Gen. S. Kaliskiego 2, 00-908 Warsaw, Poland. E-mail: abombalska@wat.edu.pl. 2212-8794/14/$27.50  2014 – IOS Press and the authors. All rights reserved