Abstract:
:The thermal transitions of fibrillar collagen are investigated with second-harmonic generation polarization anisotropy microscopy. Second-harmonic generation images and polarization anisotropy profiles of corneal stroma heated in the 35-80°C range are analyzed by means of a theoretical model that is suitable to probe principal intramolecular and interfibrillar parameters of immediate physiological interest. Our results depict the tissue modification with temperature as the interplay of three destructuration stages at different hierarchical levels of collagen assembly including its tertiary structure and interfibrillar alignment, thus supporting and extending previous findings. This method holds the promise of a quantitative inspection of fundamental biophysical and biochemical processes and may find future applications in real-time and postsurgical functional imaging of collagen-rich tissues subjected to thermal treatments.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Matteini P,Cicchi R,Ratto F,Kapsokalyvas D,Rossi F,de Angelis M,Pavone FS,Pini Rdoi
10.1016/j.bpj.2012.07.055subject
Has Abstractpub_date
2012-09-19 00:00:00pages
1179-87issue
6eissn
0006-3495issn
1542-0086pii
S0006-3495(12)00922-8journal_volume
103pub_type
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