Abstract：
:Polymers play an important role in many biological systems, so a fundamental understanding of their cross-links is crucial not only for the development of medicines but also for the development of biomimetic materials. The biomechanical movements of all mammals are aided by tendon fibrils. The self-organization and biomechanical functions of tendon fibrils are determined by the properties of the cross-links between their individual molecules and the interactions among the cross-links. The cross-links of collagen and proteoglycan molecules are particularly important in tendons and, perhaps, bone. To probe cross-links between tendon molecules, we used the cantilever tip of an atomic force microscope in a pulling setup. Applying higher forces to rat tail tendon molecules with the tip led to a local disruption of the highly organized shell of tendon fibrils and to the formation or an increase of a polymer brush of molecules sticking out of the surface. The cross-linking between these molecules was influenced by divalent Ca2+ ions. Furthermore, the molecules of the polymer brush seemed to bind back to the fibrils in several minutes. We propose that sacrificial bonds significantly influence the tendon fibrils' self-organization and self-healing and therefore contribute to toughness and strength.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Gutsmann T,Hassenkam T,Cutroni JA,Hansma PKdoi
10.1529/biophysj.104.056747subject
Has Abstractpub_date
2005-07-01 00:00:00pages
536-42issue
1eissn
0006-3495issn
1542-0086pii
S0006-3495(05)72701-6journal_volume
89pub_type
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