Calcified Tissue International

, Volume 72, Issue 6, pp 745–749 | Cite as

Volumes From Which Calcium and Phosphorus X-Rays Arise in Electron Probe Emission Microanalysis of Bone: Monte Carlo Simulation

Laboratory Investigations


Monte Carlo simulations of trajectories for electrons with initial energy of 10 keV through 30 keV were used to map the 3D location of characteristic x-ray photon production for the elements C, P, and Ca until the electrons either escaped as backscattered electrons (BSE) or had insignificant energy. The x-ray production volumes for phosphorus slightly exceed those for calcium, but both greatly exceed the volume through which BSE travel prior to leaving the sample. The x-ray volumes are roughly hemispherical in shape, and the oblate spheroid from which BSE derive occupies only the upper third to half the volume of x-ray generation. Energy-dispersive x-ray emission microanalysis (EDX) may not be secure as a method for the quantitation of BSE images of bone in the scanning electron microscope (SEM). Ca:P elemental ratios from EDX analyses may also be imperfect.


Ca:P ratio EDX BSE SEM Bone Excitation volume Emission volume Microanalysis 



This work was supported by INTAS grant 31864.


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Copyright information

© Springer-Verlag 2003

Authors and Affiliations

  1. 1.Department of Prosthetic DentistryThe Eastman Dental Institute, University College London, Gray’s Inn Road, London WC1X 8LDUK
  2. 2.Department of AnatomyUniversity College London, Gower Street, London WC1E 6BTUK

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