Synchrotron Nano X-Ray Fluorescence Spectrometry of human bone

3D and 2D Distribution of Trace Elements in Pathological Human Bone and in Histological Transition Zones An Approach with Micro and Nano Resolution Elemental Imaging by Synchrotron XRF Recent studies indicated the importance of trace elements in normal biological processes as well as disease states. By combining the fields of physics, biology and medicine in a multidisciplinary research we will improve our understanding of the role of trace elements in mineralized tissue. Within the frame of the previous FWF project P21905-N20 Synchrotron Micro X-Ray Fluorescence Imaging of Trace Elements in Articular Cartilage and Bone in Health and Disease the use of synchrotron radiation combined with a confocal Microscopic X-ray fluorescence analysis (XRF) setup proved to be an ideal instrumentation to determine the distribution of the trace elements lead, zinc, strontium and calcium in human bone and cartilage. In this new project the method should be extended by cutting-edge instrumentation to nano-XRF and nano-imaging on the experimental side and applied to other bone diseases, such as bone cancer, as well as bone healing. This will be done using the well-established cooperation with the Ludwig Boltzmann-Institute for Osteology and clinical collaborators. Project aims: Analysis of Mn distribution and concentration using SR XRF from osteoporotic femoral heads from with unknown pathogenesis and compare them with bone samples from healthy individuals of the same age group to reveal a possible link between osteoporosis and Mn content. Investigation of suspected changes in Zn distribution of healing osteoporotic fractures, for that purpose biopsies of osteoporotic vertebral compression fractures will be used. The number of men and women with osteoporosis in the EU will grow from 28 million in 2010 to 34 million in 2025, leading to escalating prevalence of disease and causing severe disability and therefore presenting a grand economic problem. Determination of the Zn and Pb distribution with new nanometer resolution beams and speciation (using XANES) of Zn and Pb in the transition zone between different phases of cartilage (tidemark) in osteoarthritis, - a prevalent form of joint disease and the most common cause of disability among adults. Analysis of the distribution of trace elements and speciation (especially Zn and Fe) to determine the chemical bindings of these elements in osteosarcomic samples. Osteosarcoma, the most common bone tumor, occurs typically during the adolescent growth spurt. Development of a quantification method for bone samples in comparison with TOF-SIMS and LA-ICP-MS. PCA evaluation and clustering will be applied. Elemental maps will be correlated with backscattered electron images of the investigated regions. Our research will shed light on the potential role of trace element in the pathogenesis of osteoarthritis, osteoporosis and bone tumor. Moreover, we intend to gain further insight into the role of trace elements in bio-mineralization.

Synchrotron radiation-induced X-ray fluorescence (SR-XRF) analysis with micro- or nanometer resolution is a method to non-destructively investigate element distribution in samples. In the course of the project experimental setups were tested for their suitability for the bone analysis. Furthermore, different bone sample sets were analyzed for their elemental distribution. It was shown that a confocal SR-XRF is preferable to detect trace elements in the tens of micrometer range compared to a full-field setup (1 publication). As confocal XRF setups at synchrotron light sources are scarce, a temporary implementation of a confocal SR-XRF system of Atominstitut was tested for the analysis of bone samples at the X-Ray Fluorescence beam line at Elettra (1 publication). For resolutions in the range of several hundred nm, the XRF setup at the B16 bending magnet test beamline at the Diamond light source proved to be a good fit. The element diffusion from biodegradable implants into surrounding bone tissue was investigated by analyzing rat bone tissue with implanted pins with different implantation duration (1 publication). In bone tumor samples of patients with osteosarcoma a higher Zn content was found in the mineralized tumor compared to the adjacent healthy mineralized bone tissue (1 publication). Gadolinium accumulations in bones of MRI patients were detected and analyzed by means of SR-XRF and SR-nXRF (publication in preparation). The investigation of thin samples containing non-calcified and calcified articular cartilage showed higher Zn and Pb content in thin structure interjacent those two tissues, the tidemark region. The thickness of the found tidemarks ranged from about 3 to 14.5 m (1 publication planned). Manganese distribution in bones, and its correlation with calcium in healthy compared to the osteoporotic bone tissue was investigated. The obtained manganese to calcium count rate ratios demonstrate that the osteoporotic samples taken from males tend to contain less manganese as opposed to healthy controls. Analysis of bone samples taken from female patients has not displayed such correlation (1 publication planned).