Performance testing a portable 109Cd XRF system for the measurement of ex vivo skin iron content in a rat model of iron overload

The ability of a 109 Cd-based portable X-ray fluorescence ( 109 Cd pXRF) system to differentiate iron (Fe) levels in the ex vivo skin of 28 rats dosed with Fe 2+ via intraperitoneal injection has been tested. The 28 animals included control rats and those dosed with either 80 mg Fe 2+ /kg or 160 mg Fe 2+ /kg. The system was able to distinguish between groups of control and dosed rats based on their measured skin iron concentration (p = 0.001 and p = 0.002). Further, linear regression analysis of individual rat skin Fe levels against Fe 2+ dose in mg/kg showed a strong correlation (r 2 = 0.84, p < 0.0001) and indicated that the system could determine whether individual animals had been dosed with Fe. Strong correlation (r 2 = 0.85, p < 0.0001) between the 109 Cd pXRF system skin Fe measurements and skin Fe measurements using a laboratory-based XRF system (which had previously shown a correlation between skin Fe and with liver Fe) suggest that 109 Cd pXRF measurements could be used to predict elevated Fe levels in the liver.