Identification of beta-carotene in an evaporitic matrix-evaluation of Raman spectroscopic analysis for astrobiological research on Mars
2009
Abstract
In this paper, Raman microspectrometry was tested as a nondestructive method of determining the lowest detectable β-carotene content in experimentally prepared evaporitic matrices—namely, gypsum, halite and epsomite. Two excitation wavelengths were compared—514.5 and 785 nm, β-carotene signals at the 0.1 to 10 mg kg−1 level—the number of registered β-carotene Raman bands differed depending on the particular mineral matrix and the excitation wavelength.
Concentrations of β-carotene of about one order of magnitude higher were identified when analysed through single crystals of gypsum and epsomite, respectively.