Collagen type I amide I band infrared spectroscopy.
Collagen fiber structure and organization have been found to vary in different tendon types. Differences have been reported in the FT-IR spectra of the amide I band of collagen-containing structures. In the present study, the FT-IR spectral characteristics of the amide I band of the bovine flexor tendon and the extended rat tail tendon were compared by using the diamond attenuated total reflectance technique. The objective was to associate FT-IR spectral characteristics in tendons with their different collagen fiber supraorganization and biomechanical properties. Nylon 6 and poly-L-lysine were used as polyamide models. Each of these materials was found to exhibit molecular order and crystallinity, as revealed by their birefringence. The following FT-IR parameters were evaluated: amide I band profile, absorption peaks and areas, and the 1655 cm⁻¹/1690 cm⁻¹ absorbance ratio. The amide I area and the 1655 cm⁻¹/1690 cm⁻¹ absorbance ratio were significantly higher for the bovine flexor tendon, indicating that its collagen fibers are richer in pyridinoline-type cross-linking, proline and/or hydroxyproline and H-bonding, and that these fibers are more packed and supraorganizationally ordered than those in the rat tail tendon. This conclusion is additionally supported by differences in collagen solubility and biochemical/biomechanical properties of the tendons.
Department of Anatomy, Cell Biology, and Physiology and Biophysics, Institute of Biology, University of Campinas (UNICAMP), 13083-863 Campinas (SP), Brazil. camposvi@unicamp.br
Benedicto de Campos
Bde C
Vidal
Maria Luiza S
ML
Mello
D000577:Amides / Q000737:chemistry*; D000818:Animals; D016880:Anisotropy; D002417:Cattle; D024042:Collagen Type I / Q000737:chemistry*; D008859:Microscopy, Polarization; D051381:Rats; D017550:Spectroscopy, Fourier Transform Infrared
D000577:Amides; D024042:Collagen Type I