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This presentation outlines the research we are developing in the area of Fourier Transform Infrared (FTIR) spectroscopic
imaging with the focus on materials of forensic interest. FTIR spectroscopic imaging has recently emerged as a powerful
tool for characterisation of heterogeneous materials. FTIR imaging relies on the ability of the military-developed infrared
array detector to simultaneously measure spectra from thousands of different locations in a sample. Recently developed
application of FTIR imaging using an ATR (Attenuated Total Reflection) mode has demonstrated the ability of this
method to achieve spatial resolution beyond the diffraction limit of infrared light in air. Chemical visualisation with
enhanced spatial resolution in micro-ATR mode broadens the range of materials studied with FTIR imaging with
applications to pharmaceutical formulations or biological samples. Macro-ATR imaging has also been developed for
chemical imaging analysis of large surface area samples and was applied to analyse the surface of human skin (e.g.
finger), counterfeit tablets, textile materials (clothing), etc. This approach demonstrated the ability of this imaging
method to detect trace materials attached to the surface of the skin. This may also prove as a valuable tool in detection of
traces of explosives left or trapped on the surfaces of different materials. This FTIR imaging method is substantially
superior to many of the other imaging methods due to inherent chemical specificity of infrared spectroscopy and fast
acquisition times of this technique. Our preliminary data demonstrated that this methodology will provide the means to
non-destructive detection method that could relate evidence to its source. This will be important in a wider crime
prevention programme. In summary, intrinsic chemical specificity and enhanced visualising capability of FTIR
spectroscopic imaging open a window of opportunities for counter-terrorism and crime-fighting, with applications
ranging from analysis of trace evidence (e.g. in soil), tablets, drugs, fibres, tape explosives, biological samples to
detection of gunshot residues and imaging of fingerprints.
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