利用二维红外相关光谱研究胶原/透明质酸共混物的相互作用

Specific Interaction Study in Collagen/Hyaluronic Acid Blends by Two-Dimensional Infrared Correlation Spectroscopy

以胶原/透明质酸共混物中透明质酸的含量为外扰,利用二维红外相关光谱法研究了胶原/透明质酸共混物的构象变化及它们之间的相互作用。研究发现,1 694,1 524与1 241 cm-1归属于胶原酰胺带的C=O对称伸缩振动、N—H摇摆与N—H面内变形振动峰之间存在同步正交叉峰,表明随着透明质酸组分的增加,胶原的链段构象发生了变化。当胶原/透明质酸共混体系中透明质酸含量由0增至50%时,1 045cm-1归属于透明质酸的C—OH伸缩振动峰与1 694 cm-1归属于胶原C=O对称伸缩振动峰存在同步负交叉峰,表明透明质酸的O—H与胶原分子的C=O之间形成了氢键;当透明质酸含量从50%增至90%时,1 045 cm-1的同步峰几乎消失,而在Φ(1 694,1 524),Φ(1 694,1 241),Φ(1 524,1 241)出现的正交叉峰反而增强,说明透明质酸的O—H不再与胶原形成氢键,而是透明质酸的C=O与胶原分子的N—H之间形成氢键,致使胶原构象发生了变化。

Conformational changes and specific interactions in the collagen/hyaluronic acid blends were studied by two-dimensional infrared correlation spectroscopy with the interruption of the component of hyaluronic acid in collagen/hyaluronic acid blends.It was found that the synchronous crosspeaks,derived from stretching vibrations of C=O at 1 694 cm-1,wagging of N—H at 1 524 cm-1 and in-plane deformation of N—H at 1 241 cm-1 of collagen,were indicative of local conformational changes of collagen.The synchronous negative cross-peak between stretching vibrations of C—OH of hyaluronic acid at 1 045 cm-1 and streching vibrations of C=O of collagen at 1 694 cm1 suggested that the interaction of hydrogen bonding existing between O—H of HA and CO of collagen with the content of HA varied from 0% to 50%.With the content of HA more than 50%,the cross-peak at 1 045 cm-1 disappeared in synchronous correlation spectra while the intensity of cross-peak at（1 694,1 524）,（1 694,1 241）,（1 524,1 241） increased,which indicated that no interaction was found between O—H of HA and collagen,however,the interactions of hydrogen bonding existed between C=O of HA and N—H of collagen,resulting in the conformational changes of collagen.