碳-13核磁共振波谱法对甲醛和胶原交联反应的研究

本文以碳-13富集的甲醛为交联剂,用核磁共振波谱法对甲醛和明胶的交联反应进行了直接跟踪和详尽研究。使此反应的过程,交联反应发生的方位及其结果得到了更为客观的认识。结果表明,和蛋白质反应的主要成分是甲醛单体(水合物)而非聚合物。其次,交联反应所形成的亚甲基桥是在赖氨酸(或羟基赖氨酸＊)的侧链氨基和精氨酸的侧链胍基之间,反应属典型的曼尼克反应(Mannich Reaction)。而不是在赖氨酸的侧链氨基之间。此反应也有少量精氨酸胍基的羟亚甲基衍生物生成。(＊以下只用赖氨酸来代替二者)

~13C NMR Studies of Crosslinking Reaction between Gelatin and Formaldehyde

Current research has focused on direct studies of crosslinking rea- ction of gelatin with ~(13)C-enriched formaldehyde by means of Nuclear Magnetic Resonance (NMR) spectroscopy, revealing the crosslinking reaction sites in protein, process and the reaction results. The results of this study have shown that it is the monomer(hydrate) of formalde- hyde which reacts with gelatin but not the polymers. Additionally, the reaction forms crosslinks in the from of -CH_2- between amino groups of lysine (or hydroxy-lysine) residues and the guanidine groups of argini- ne.This reaction is typical Mannich Reaction.There is also a little hpdro- xymethylene derivatives of arginine formed.No participation of peptide bond or amide group has been found.