Nanomechanics of UV irradiated collagen fibrills

• Applicant: Professor Dr. Robert Stark
• Subject Area: Biophysics ; Biomaterials ; Mechanical Properties of Metallic Materials and their Microstructural Origins
• Term: from 2015 to 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 276304632

Collagen in the form of elongated fibrils possesses exceptional properties and is the main structural protein of the human body. Owing to its complex and hierarchical structure collagen has a very high (ultimate) tensile strength. Thus, collagen adds tensile strength and resilience to skin, tendon, vascular ligature, organs, or bone. In technology collagen is an important substrate in cell culture and serves as a scaffold in tissue engineering. In these examples, the mechanical properties of collagen play a prominent role. The mechanical properties of collagen are determined by internal cross-linking. In an organism, cross-linking occurs during synthesis and assembly of the fibrils. External influence, however, such as ultraviolet (UV) radiation or temperature treatment also affect the mechanical properties because additional cross-links are created. Extended treatment may lead to a weakening due to proteolysis. However, on the scale of individual fibrils it is not clear which influence UV radiation and temperature have. Thus, the nanomechanics of treated collagen shall be investigated with the aid of an atomic force microscope. Confocal Raman spectroscopy shall contribute to a spatially resolved chemical analysis. The project aims to show that the nanomechanical properties of collagen type I can be modified in a controlled manner with UV irradiation and temperature treatment. On a longer perspective the results shall contribute to collagen matrices or scaffolds with controlled mechanical properties.

• DFG Programme: Research Grants