engleski

Characterization of pollen by vibrational spectroscopy

Classification, discrimination and biochemical assignation of vibrational spectra of pollen samples belonging to 43 different species of Pinales order has been made by three different vibrational techniques. A comparative study of transmittance and reflectance Fourier transform infrared (FT-IR) and FT-Raman spectroscopies, was based on substantial variability of pollen grains size, shape and relative biochemical composition. Depending on the penetration depth of the probe light, vibrational spectra acquire predominant information either on pollen grain walls (FT-Raman) or intracellular material (transmittance FT-IR). Compared with the other two methods transmittance FT-IR obtains more comprehensive information and as a result achieves superior spectral identification and discrimination of pollen. The results strongly indicate that biochemical similarities of pollen grains that belong to particular plant genus or family lead to similar features in corresponding vibrational spectra. The exploitation of that property in aerobiological monitoring was demonstrated by simple and rapid pollen identification based on relatively small spectral libraries, with the same (or better) taxonomic resolution than that provided by optical microscopy. Therefore, the clear correlation between vibrational spectra and pollen grain morphology, biochemistry and taxonomy is obtained, while successful pollen identification illustrates practicability of such approach in environmental studies. Acquisition of infrared spectra of pollen collected on the IR transparent plastic tape clearly demonstrates the applicability of FT-IR method in standard aeroallergen monitoring networks as rapid, economical and bias-free alternative to optical microscopy.

FT-IR spectroscopy ; FT-Raman spectroscopy ; pollen ; aeroallergen ; identification ; classification

nije evidentirano