EVALUACIÓN DE LOS PARÁMETROS DE UN SISTEMA EDXRF PARA LA OBTENCIÓN DE IMÁGENES 2D DE GADOLINIO EN FANTOMAS TUMORALES

R. SAAVEDRA; M. SANTIBANEZ; M. VALENTE; M. VASQUEZ; R. FIGUEROA

Carelos Paz

Congreso; 7mo Congreso ALFIM & 13avo Congreso SAFIM; 2016

ALFIM & SAFIM

During the last years it was proposed has been proposed the utilization of Gold and Silver nanoparticles like bio-markers when are bound to molecules like antibodies, which are linked tospecifics cell receptors. The advances achieved in this field promoved have proposed the future useof the nanoparticles for detection of small clusters of infiltrating cancer, providing information oftumor characteristics to map the disease state, distribution and radiosensibility of the tumor cellsand generating images to produce personalized cancer therapy regimes. Therefore, the use of Goldand Silver nanoparticles with specific markers would provide information of these bio-parameters,and thus individualize treatments depending on the conditions of the tumor microenvironment. Oneof the common challenges associated with the use of that presented the using these new agents is todevelop methodologies for in vivo detection, simultaneously and with greater sensitivity whennanoparticles are administered provided to the organism. This work presents a simulated andoptimized EDXRF system, which allow simultaneously quantify in vivo Gold and Silver nanoparticlesinto tumor phantoms, generating a multi-parametric imaging of specific tumor characteristics. Thesystem was simulated using XMI-MSIM software designed to predict the XRF spectral response usingMonte Carlo simulations. The studied setup is comprised of an mini X-ray tube and a set of Se, Sr, Y,Zr, filters, for exiting the gold L3-edge, and Cd, In and Sn, filters, for exiting the silver K-edge. Thissimulated setup was configured with variable thickness, for emit simultaneously two energeticallyspectrally narrow beams centered on a specific excitation energy. The merit figures used foroptimization and adjustment of the composition and filters thickness were minimizing the detectionlimit and radiation exposure. For determining the experimental detection limit, severalconcentrations ranging from 0.05 to 10 mgAu/ml were measured into the tumor phantomsconsidering a statistical fluctuation with a 95% of confidence level. The ranging of concentrationstudied corresponds to the possible gold and silver concentrations expected to be found in future invivo application in human.