Pathologies related to abnormal deposits in dermatology: a physico-chemical approach

Although numerous pathologies are associated with abnormal skin deposits, these remain poorly described, as accurate characterization continues to present a challenge for dermatologists. Their submicrometer size as well as their diverse chemistry require various characterization tools. We aim to exemplify characterization of endogenous and exogenous skin deposits in some selected skin diseases using different physico-chemical techniques. We begin with a presentation of selected diseases associated with skin deposits. We then present those of our results which show their variety of structure, location and chemical composition, obtained with various tools: Field Emission Scanning Electron Microscopy coupled with Energy Dispersive X-ray Spectroscopy, X-ray fluorescence, vibrational spectroscopies, as well as techniques specific to synchrotron radiation. Our results constitute a real opportunity to improve diagnosis, and to understand the pathogenesis of many skin diseases, and opportunities for therapeutic intervention.