Open AccessThe effects of UV irradiation on collagen D‐band revealed by atomic force microscopy
Author(s) -
Kontomaris Stylianos V.,
Yova Dido,
Stylianou Andreas,
Balogiannis Giorgos
Publication year - 2014
Publication title -
scanning
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.359
H-Index - 47
eISSN - 1932-8745
pISSN - 0161-0457
DOI - 10.1002/sca.21185
Subject(s) - nanoindentation , irradiation , collagen fibril , atomic force microscopy , fibril , materials science , resolution (logic) , chemistry , biophysics , nanotechnology , composite material , artificial intelligence , computer science , nuclear physics , biology , biochemistry , physics
Summary The objective of this paper was to investigate the influence of UV irradiation on collagen D‐band periodicity by using the AFM imaging and nanoindentation methods. It is well known than UV irradiation is one of the main factors inducing destabilization of collagen molecules. Due to the human's skin chronic exposure to sun light, the research concerning the influence of UV radiation on collagen is of great interest. The impact of UV irradiation on collagen can be studied in nanoscale using Atomic Force Microscopy (AFM). AFM is a powerful tool as far as surface characterization is concerned, due to its ability to relate high resolution imaging with mechanical properties. Hence, high resolution images of individual collagen fibrils and load‐displacement curves on the overlapping and gap regions, under various time intervals of UV exposure, were obtained. The results demonstrated that the UV rays affect the height level differences between the overlapping and gap regions. Under various time intervals of UV exposure, the height difference between overlaps and gaps reduced from ∼3.7 nm to ∼0.8 nm and the fibril diameters showed an average of 8–10% reduction. In addition, the irradiation influenced the mechanical properties of collagen fibrils. The Young's modulus values were reduced per 66% (overlaps) and 61% (gaps) compared to their initial values. The observed alterations on the structural and the mechanical properties of collagen fibrils are probably a consequence of the polypeptide chain scission due to the impact of the UV irradiation. SCANNING 37:101–111, 2015. © 2014 Wiley Periodicals, Inc.