Early Imaging Applications

The vibrahonal spectroscopy of biological material has been a fruitful area of study and practical use for more than four decades, with biological products having been analyzed qualitahvely with mid-IR systems, and quantitatively with near-lR. For mid-IR spectroscopy in most cases, homogenates or solid materials are analyzed on a macro scale in transmission as nujol mulls, or as KBr pellets or by diffuse reflechon or reflection absorption techniques. 

The commercial sorting of lemons on a massive scale was achieved as early as the 1980s by Sunkist. In this case, each lemon was inspected for spots on the skin 

The spatial resolution of FT-IR microspectroscopy, without sacrificing spectral quality and resolution, makes imaging possible. Shortly after the introduction of the first research-quality IR microscope by Messerschmidt and Sting in 1986, Wetzel, Messerschmidt and Fulcher reported spectra obtained from wheat kernel transverse sections in situ, and compared them with flour milling fractions [7]. This was achieved with an accessory IR-PLAN microscope optically interfaced to a Nicolet interferometer bench. Subsequently, at the Agriculture Canada laboratory the same model IR-PLAN was interfaced to a Bomen Michelson IR 100 spectrometer such that, over the period of a year, transverse sections of wheat kernels, vanilla beans, peppercorns and soybeans were manually line-mapped to reveal any differences in microchemical structural characteristics between their different botanical parts [8]. 

Wavenumber (cm Figu re 7.2 Synchrotron infrared microspectroscopy with 6 x6pm confocal operation and truncation at low wavenumber due to diffraction showing (a) The scutellum portion of the germ with high 1 740cm lipid compared to 1650cm protein (b) The 

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Yes, this sounds like science fiction, but the use of SPECT or PET/CT (and some early magnetic resonance imaging applications) (see also Part V, Chapters 4 and 5)... 

Owing to their unique chemical and physical structure, carbon-based NMs are potential candidates for a variety of biomedical applications, including early imaging, NIR photothermal therapy, photoacoustic imaging, and drug delivery. When these NIR NMs are introduced into complex biological systems, the related risk assessment is of considerable importance to both human and environmental health. Based on current studies, we mainly discuss the in vitro and in vivo toxicity of CNTs and graphene. 

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