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Evaluation of detection and preservation of carotenoid biomarkers in Martian analogues using portable Raman spectrometer
Novotný, Radek ; Culka, Adam (advisor) ; Němec, Ivan (referee)
Recent missions of the space agencies NASA, ESA and Roskosmos have focused on searching for traces of life, among other things. They use a range of analytical instruments such as Raman spectroscopy, infrared spectroscopy and GS-MS chromatography. They are looking for biological indicators (biomarkers) that could indicate the past but also the present activity of living organisms. In this thesis, it was proposed to observe changes in the concentration of a biomarker (the pigment betacarotene) in a substrate consisting of a mixture of sulphates. The conditions would be as close as possible to those on Mars. On the surface of this planet, due to the thinner atmosphere and the lack of an ozone layer, the UV component of UVC radiation, which has degradative effects on organic material, is much more strongly applied. Furthermore, perchlorate, a strong oxidising agent also found in Martian soil (regolith), was present in this substrate. Based on these parameters, samples were prepared that had an arrangement in three layers, two of which contained the biomarker beta-carotene and perchlorate. In order to better compare the changes during the experiment, two pigment concentrations of 10 ppm and 100 ppm were chosen. The samples thus prepared were irradiated in four-day and eight-day stages by a light source...
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Estimation of Raman spectrometric instruments (785 nm excitation) for detection of dark minerals
Šimon, Jan ; Jehlička, Jan (advisor) ; Machovič, Vladimír (referee)
Summary: Raman spectroscopy is a widely used method in geoscience fields. Using a portable Raman spectrometer is possible to identify different materials, Raman spectrometer will participate in the survey the Martian surface. Its use is widely applied in mineralogy. There was measured a set of dark, green and some bright minerals of different mineralogical system groups that have been assessed the applicability of the chosen detector excitation at 785 nm mainly off-road equipment. The obtained spectra were measured off-road equipment ahura at excitation 785 nm and laboratory equipment InVia Renishaw and there were used lasers at excitaion of 785 nm and 514 nm. It was set of these minerals: Prehnite, Sulphur, Tyrkenit (howlit), Pyroxene (diopside), Libethenite, Toutmaline (verdelite), Dioptas, Klinoklas, Langit, Jadeit, Pseudomalachit (ehlit), Actinolite, Epidote, Augite. Results are composed of field measurement device Ahura, with excitation 785 nm and laboratory apparatus Invite Renishaw excitations with 785 nm and 514 nm. Measured values are arranged in tables, where the measurements are compared with each other, including literature and reference graphically demonstrated in the form of spectra. Subsequently evaluated their measurability. Keywords: Raman spektroscopy, portable Raman spectrometer,...
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