A espectroscopia fotoacústica como ferramenta para o estudo de biomoléculas.

Abstract

The biomolecules are directly linked to the energy metabolism of living beings and therefore their maintenance in the body is essential for the conservation of good health. These biomolecules, mostly, are present in several materials like fruits, greens and vegetables, which are associated with many properties, among the most important ones we may mention the pharmacological properties, like antioxidant agent, reducing agent and antiinflammatory agent that are of great value to human health. This has motivated several scientific researches with the aim of better characterize these materials and differentiate the entities that make them multifunctional, among which the biomolecules represent the interest of this work. Furthermore, these studies are performed through techniques that require extraction methods to be applied to the interest material in order to extract the biomolecules so that they may be studied. This ends up changing the natural conditions of those molecules making the result different from the expected. This work aims to use photoacoustic spectroscopy as a tool for studying biomolecules and optical characterization of organic materials in view of their ability to probe materials without the primary need to perform an extraction procedure. To this end, new systems and methods were developed that allowed the execution, hardware automation, data acquisition from the experiment and a better interpretation of them. These methods were applied and tested on materials that contain biomolecules and that are easily accessible to the Brazilian population, such as fruits and vegetables. The samples of interest were characterized by photoacoustic spectroscopy, and the results were analyzed using the second derivative and phase methods. The UV-Vis spectroscopy and TDDFT computer simulations techniques were used as a comparative background to the photoacoustic’s results as well. The results were promising and several facets of the photoacoustic spectroscopy were studied showing its ability to probe organic physical systems in a crystalline, liquid, solid and in natura form.