Fourier-transform mid-infrared FPA imaging of a complex multicellular nematode

Here we report on the application of mid-IR imaging to a complex multicellular organism, a nematode. Despite the increase in sample complexity and sample thickness from previously measured cells and tissue sections, it is still possible, through the application of hierarchical cluster analysis, to elucidate biochemical information and spatial distribution information that can be linked to different tissue types in the nematode, namely somatic and non-striated muscle and the collagen rich cuticle. Comparison of HCA clusters from individuals from different species shows clusters can be associated specifically to a particular species, but that few clusters are shared between individuals from different species. In addition, using a synthetic fibre as a model for the nematode, we also show that the IR spectra can be affected by Mie scattering type baseline oscillations which are especially severe towards the edges of the fibre/nematode, but that these can be, to some extent, corrected for using currently available correction algorithms prior to cluster analysis. (C) 2011 Published by Elsevier B.V.