Bio: Dr. Carlos Alberto Pérez is a researcher at the Coherent X-ray Nanoprobe (Carnaúba) group of the Brazilian Synchrotron Light Laboratory (LNLS) at the fourth-generation synchrotron machine Sirius. His main fields of expertise are atomic and molecular physics and synchrotron radiation with emphasis on X-ray fluorescence (XRF) analysis, X-ray absorption spectroscopy (XAS), and advanced X-ray imaging methods using X-ray micro- and nanoscopic beams. Current research involves trace element studies in animal and plant tissues, biogeochemistry of environmentally important trace elements, and environmental toxicology focusing on applications in agro-environmental, biomedicine, and material science. Current research interests involve trace elements studies in biological and plant tissues, biogeochemistry of environmentally important trace elements, environmental toxicology and nanotoxicology. Dr. Pérez´s experience is important for his leading experiments involving the analysis of 2D and 3-D tomographic imaging collected at different contrasts.

Abstract: Metals can be separated into two categories: essential and non-essential. Essential metal ions function as protein cofactors in a wide variety of biological processes and are non-toxic when present in trace amounts in an organism but can be toxic if concentrations exceed a threshold. Non-essential metals have no biological function and are toxic to the organism in even trace amounts. On the other hand, nanomaterials have revolutionized the way we live in this world. Significant advances have been made in the past few years in studying the relationship between the physicochemical properties of nanomaterials and their toxicity. General concerns have been raised about the effects on the ecosystems due to the extensive transformation of Engineered Nanomaterials (ENMs), many of them with unknown properties. Given the complexity and heterogeneity of these systems, analytical techniques capable of preserving the main features of the volume under investigation are well-preferred. CARNAÚBA is a nanofocused, multi-analytical and Coherent X-ray imaging beamline of Sirius which provides the main capabilities for studying those samples in different environmental conditions. This presentation will show the main layout and experimental arrangements of the beamline as well as several examples of samples of relevance for agricultural sciences, ecotoxicology and nanotoxicology.