Spectrometry methods for in vivo bone strontium measurements

In vivo x-ray fluorescence (XRF) and dual-photon absorptiometry (DPA) are two widely accepted radiation-based measurement techniques. The first one is mainly used for the measurement of toxic elements in the human body, while the second one is clinically used to measure bone density. In this paper we present a literature review of the application of these two techniques to in vivo strontium measurements. Strontium is a natural constituent of the human skeleton, where it may exert beneficial or detrimental effects depending on the dietary intake and other factors. Recently, several medical publications have focused on the beneficial effects on bone of pharmacological dosages of strontium, especially with regard to its anti-osteoporotic effects. However, the mechanism by which strontium exerts its therapeutic action is still not known. XRF and DPA have the potential of providing unique information on bone strontium concentration, retention and elimination that cannot be gained at the moment in any other way.