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  • 1 Faculté de Médecine de la Timone Laboratoire de Biophysique 13385 Marseille France
  • 2 Faculté des Sciences de St. Jérôme Laboratoire de Physique des Matériaux 13397 Marseille France
  • 3 Silesian University Institute of Physics and Chemistry of Metals Bankowa 12 PL-40-007 Katowice Poland
  • 4 DRFMC/SP2M/NM. CEA/Grenoble 17 rue des Martyrs 38054 Grenoble France
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Abstract  

Lifetime measurement in Positron Annihilation Spectroscopy (PAS) is applied to the study of free-volume collagen characteristics as a function of concentration. The lifetimes of positrons were measured by a conventional fast-fast coincidence system. All lifetime data are fitted in three components by using the computer program POSITRON-FIT and resolved. For each concentration, lifetime distributions were analyzed in order to obtain the different components, thus we have observed three components of which one long component τ3. This long lived component can be associated with a pick-off annihilation of ortho-positronium (o-Ps) trapped in free volumes of amorphous region. This investigation shows the potential of positron annihilation spectroscopy in the study of biopolymer microstructures.