1 General Overview on Vibrational Spectroscopy Applied in Biology and Medicine
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Fast development of Ft-IR techniques enabled extensive application of IR imaging for distribution studies of main components in the plant material. Several works
have been focused on changes in wood tissues including cell wall modification
during maturation [14], fungi degradation [15], steam treatment [16], and transgenic modification [17] to show tissue specific accumulation/degradation patterns.
IR imaging has been applied for the analysis of wheat endosperm cell wall composition changes under the impact of environmental conditions [18]. differentiation
between wheat cultivars based on variety of endosperm cell walls [19] was demonstrated. IR imaging technique can be more successful than conventional chemical
methods in indicating differences between similar chemotypes, e.g. between wild
and mutant type of Arabidopsis [20].
high spatial resolution of IR imaging can be achieved by using a synchrotron
source. Synchrotron radiation-based (SR) Ft-IR imaging has already been successfully used to examine plant tissue in, e.g. cereals [21]. however, application of
FPA detector in IR microspectroscopy has been shown to achieve similar results to
synchrotron measurements at the single cell level [22]. Finally, IR imaging based on
FPA detector can be applied for bigger areas of a plant such as whole root sections
and leaves to observe tissue specific distribution of the studied compounds with
comparable spatial resolution and signal-to-noise ratio.
Results from Raman mapping or IR imaging are usually analyzed by comparing
integral intensity or by chemometric methods such as Principal Component Analysis (PCA) and Cluster Analysis (CA) to obtain two-dimensional maps and images.
Apart from qualitative analysis of plant material, vibrational spectroscopy is a
powerful tool for quantitative studies of individual plant components. this method
does not require extraction or separation of the constituents in contrary to widely
used chromatographic methods. vibrational methods allow the quantification of
new samples directly from spectral data. thus, IR and Raman spectroscopy can be
used as fast and nondestructive calibration methods for quantification of relevant
component contents in plants and related products. Linear calibration based on vibrational spectra and chromatographic data can be used for reliable prediction of the
product content as well as for the efficient selection of high-quality single products
in industry. It seems to be a powerful tool for a rapid and low-cost alternative quality control method of food production processes.
1.3 Biomedical Application
In the biomedical field it is very desirable to develop innovative and widely used
techniques to study the uptake and distribution of bioactive substances. the optical
methods do not require any additional labeling or special photophysical properties of
the investigated sample. the conventional imaging techniques are often limited by
the insufficient sensitivity, specificity and spatial resolution, however the vibrational
spectroscopy can be applied to study even single animal cells and various tissues.
vibrational spectroscopy combined with microscopy has become a powerful diagnostic tool in the biomedical applications. Raman and infrared absorption
7
Fast development of Ft-IR techniques enabled extensive application of IR imaging for distribution studies of main components in the plant material. Several works
have been focused on changes in wood tissues including cell wall modification
during maturation [14], fungi degradation [15], steam treatment [16], and transgenic modification [17] to show tissue specific accumulation/degradation patterns.
IR imaging has been applied for the analysis of wheat endosperm cell wall composition changes under the impact of environmental conditions [18]. differentiation
between wheat cultivars based on variety of endosperm cell walls [19] was demonstrated. IR imaging technique can be more successful than conventional chemical
methods in indicating differences between similar chemotypes, e.g. between wild
and mutant type of Arabidopsis [20].
high spatial resolution of IR imaging can be achieved by using a synchrotron
source. Synchrotron radiation-based (SR) Ft-IR imaging has already been successfully used to examine plant tissue in, e.g. cereals [21]. however, application of
FPA detector in IR microspectroscopy has been shown to achieve similar results to
synchrotron measurements at the single cell level [22]. Finally, IR imaging based on
FPA detector can be applied for bigger areas of a plant such as whole root sections
and leaves to observe tissue specific distribution of the studied compounds with
comparable spatial resolution and signal-to-noise ratio.
Results from Raman mapping or IR imaging are usually analyzed by comparing
integral intensity or by chemometric methods such as Principal Component Analysis (PCA) and Cluster Analysis (CA) to obtain two-dimensional maps and images.
Apart from qualitative analysis of plant material, vibrational spectroscopy is a
powerful tool for quantitative studies of individual plant components. this method
does not require extraction or separation of the constituents in contrary to widely
used chromatographic methods. vibrational methods allow the quantification of
new samples directly from spectral data. thus, IR and Raman spectroscopy can be
used as fast and nondestructive calibration methods for quantification of relevant
component contents in plants and related products. Linear calibration based on vibrational spectra and chromatographic data can be used for reliable prediction of the
product content as well as for the efficient selection of high-quality single products
in industry. It seems to be a powerful tool for a rapid and low-cost alternative quality control method of food production processes.
1.3 Biomedical Application
In the biomedical field it is very desirable to develop innovative and widely used
techniques to study the uptake and distribution of bioactive substances. the optical
methods do not require any additional labeling or special photophysical properties of
the investigated sample. the conventional imaging techniques are often limited by
the insufficient sensitivity, specificity and spatial resolution, however the vibrational
spectroscopy can be applied to study even single animal cells and various tissues.
vibrational spectroscopy combined with microscopy has become a powerful diagnostic tool in the biomedical applications. Raman and infrared absorption