Abstracts Category : Other

X-RAY FLUORESCENCE MEASUREMENT OF IRON ACCUMULATION IN SKIN AS A SURROGATE MARKER FOR IRON LEVELS IN CRITICAL ORGANS AND TOTAL BODY IRON BURDEN

by Erica Dao

This thesis investigates the use of x-ray fluorescence (XRF) measurements of skin ironconcentration as a non-invasive surrogate marker for total body iron burden. Rats wereoverloaded with iron dextran via intraperitoneal injection to investigate trends in ironaccumulation in skin and organs. The skin, heart, liver, and kidney of the animals werecollected and the iron concentrations were measured using the Huber XRF system andthe polarized energy dispersive x-ray fluorescence (PEDXRF) system. When measuredin the Huber XRF system, a very strong quadratic correlation was found between skiniron concentration and liver iron concentration (R2=0.92). In the same system, skiniron concentration had a moderately strong linear correlation with heart and kidney ironconcentration (R2=0.53 and R2=0.65, respectively). Measured in the PEDXRF system,heart and kidney iron concentrations were again linearly correlated with skin ironconcentrations (R2=0.34 and R2=0.31, respectively). Liver iron concentration againshowed a quadratic correlation with skin iron concentration (R2=0.64). Therefore, itwas demonstrated that skin iron concentrations can act as a surrogate marker for organiron concentrations in rats, especially for the liver. The feasibility of using an OlympusInnov-X Delta Professional Handheld XRF Analyzer, a commercial portable x-rayfluorescence (PXRF) device, as a tool for in vivo skin iron analysis was investigated.The same rat skin samples measured in the previous experiment were measured usingthe PXRF device and compared with the organ iron concentrations as measured usingthe Huber XRF system. The heart and kidney showed linear correlations with skin ironconcentration (R2=0.45 and R2=0.36, respectively). The liver showed the strongestcorrelation with a moderately strong quadratic correlation with R2=0.74. It wasdetermined that using Beam 3 in the Soil mode of this device resulted in equivalentand effective dose rates of 23010mSv/min and 2.30.1mSv/min, respectively. Thus,the PXRF device has shown promise as a potential tool for measuring in vivo skiniron levels. Thesis Master of Science (MSc)Advisors/Committee Members: Farquharson, Michael J, Medical Physics.