Feasibility evaluation of the application of Silicon Drift Detectors in studies of drug delivery in liver

This work aims to assess the feasibility of studying the distribution of drugs and diagnostic agents in biological specimens by means of XRF detected with high-resolution and high sensitivity Silicon Drift Detectors. In the present study we have employed as diagnostic agent a gadolinium complex (Gadocoletic acid trisodium salt - B22956/1). The primary excitation beam was the light of the SYRMEP beamline of the Elettra synchrotron light source. For calibration purposes we analyzed solutions of the Gd complex in water at different dilutions. The minimum level of Gd detected is 5 mug/ml. We measured the Gd complex distribution in different organs (liver, kidney, spleen, lung) and in blood of mice at different times after a single injection of B22956 (250 mg/Kg body weight) and the Gd complex uptake in human liver-derived cells. This technique will allow the measure of pharmacokinetics and the study of the homogeneity of drug distribution inside organs providing a new tool in the development, follow-up and tracking of drug delivery in vitro.