FT-IR spectroscopic imaging microscopy of wheat kernels using a Mercury–Cadmium–Telluride focal-plane array detector

A 64×64 Mercury–Cadmium–Telluride (MCT) focal-plane array detector attached to a Fourier transform infrared (FT-IR) microscope was used to spectroscopically image 8-μm-thick cross-sections of wheat kernels in the fingerprint region of the infrared spectrum. After fast-Fourier transformation of the raw image interferograms, the data can be displayed as either a series of spectroscopic images collected at individual wavelengths, or as a collection of IR spectra obtained at each pixel position in the image. Image contrast is achieved due to the intrinsic chemical nature of the sample at each pixel location in the image. Individual cell layers near the outer portion of the wheat kernel, as well as the primary root within the germ, can be clearly differentiated in the IR images as a result of this enhanced chemical contrast.