应用拉曼光谱技术研究了长波紫外(Ultraviolet-A, UV-A)辐射对Ⅰ型胶原的损伤, 检测了Ⅰ型胶原及其经过90 min的UV-A辐射后的拉曼光谱, 得到了一个较完整的Ⅰ型胶原紫外损伤机制。 实验结果表明: 90 min的UV-A辐射导致Ⅰ型胶原分子内氢键断裂、 氢键体系发生变化, 肽链的螺旋度减少, 逐渐解螺旋, 无规卷曲等无序构象增加。 此外, UV-A辐射使Ⅰ型胶原分子内脯氨酸的羟基化程度降低。 这些变化必然会引起Ⅰ型胶原三螺旋结构的损伤, 并导致皮肤光老化过程中组织内胶原纤维的破坏。

Raman spectroscopy was used to study the influence of ultraviolet-A(UV-A) radiation on collagenⅠ. The Raman spectra of collagenⅠ and that after 90 min UV-A radiation were reported. The results proved that irradiation with 90 min UV-A caused the change in the structures of collagenⅠ. Intramolecular hydrogen bonds were broken, and the hydrogen bonding system was changed. The intensity of helix was decreased, while the intensity of the disordered conformation in proteins such as random coil was increased. Otherwise, the UV-A radiation influenced the hydroxylation of proline and the content of hydroxyproline was reduced. The changes caused by UV-A radiation could damage the triple helical structure of collagenⅠ. It would lead to a series of changes, such as the destruction of collagen fibers during the photoaging of skin.