Photoacoustic response of a common starfish tissue

Abstract

Abstract.A sample of common starfish (Asterias Rubens) tissue has been prepared in the shape of a film to study its photoacoustic (PA) response. A broad absorption band in the PA spectrum is detected in the visible region (a peak at about 570 nm), while the ultraviolet region is distinguished by the absorption bands originating from π → π* and π → n charge transfer transitions. The visible PA spectrum strongly depends on decomposition of sample in the open air. The PA spectrum measured by us is very similar to those obtained earlier for the other living organisms, e.g. Trunculariopis Trunculus and Sea Urchin. The absorption band near 570 nm is similar to that found for spermidine, which is of importance in the information transfer to DNA. The results obtained in this work confirm experimentally that geologically very old organisms have been absorbing especially intensely in that part of solar spectrum for which the water is transparent.

Photoacoustic spectra of green and red leaves of ficus Benjamina plant

“…In the visible region a very broad and intense PA spectrum with the maximum at about 570 nm is observed for some living organisms (e.g., Trunculariopsis Trunculus, Sea Urchin, and Asterias Rubens [8,17,18]). Deconvolution of the PA spectra of the copper (II) complexes of spermidine reveals a fine structure arising from interaction with the crystal field [11][12][13].…”

Photoacoustic Detection of Weak Absorption Bands in Infrared Spectra of Calcite

“…Calcite, the material under investigation in the present work, has been widely studied using FT-IR transmission and ATR techniques, but very little by PAS. [4][5][6][7][8] Calcium carbonate polymorphs, including CaCO 3 , appear naturally in many instances and are of importance to materials scientists, archaeologists, and those who study biomineralization. [9][10][11] FT-IR spectroscopy offers distinct advantages relative to diffraction-based techniques because calcium carbonate polymorphs can be easily differentiated from each other even when they are poorly crystallized.…”