The synchronous fluorescence spectroscopy and two dimensional correlation analysis method were applied to study the aggregation behavior of acid-soluble collagen solutions (0. 2,0. 4 and 1. 6 mg·mL-1 )during the heating process of 10~70 ℃. It was found that the fluorescence excited at 292 and 282 nm (Δλ= 9 nm)belongs to the tyrosine (Tyr)residues which partici-pate in forming hydrogen bonds or not,respectively.The two dimensional correlation analysis with the temperature varying showed that with the temperature increased (10~30 ℃)hydrogen bonds among collagen molecular with Tyr residues formed in the 0. 2 mg·mL-1 collagen solution,while the higher aggregations of collagen molecular and hydrophobic micro-domains ap-peared in the 0. 4 and 1. 6 mg·mL-1 collagen solutions.With approaching the denatured temperature of collagen (36~38 ℃), the hydrophobic micro-domain and aggregates seemed to be broken in the 0. 4 and 1. 6 mg·mL-1 collagen solutions,however the hydrogen bonds in the 0. 2 mg·mL-1 were stable.Above the denaturation temperature of collagen,the triple-helix structure of collagen molecular in solution of each concentration tended to be loose.In the heating process of 45~70 ℃,this trend was more obvious.%采用恒波长同步荧光法和二维相关分析技术研究了不同浓度Ⅰ型胶原溶液中胶原分子聚集行为随温度升高（10～70℃）的变化规律。选取0．2，0．4，1．6 mg·mL－1的胶原溶液，在初始温度下各浓度溶液中胶原分子分别处于单分子状态、较低程度和较高程度的聚集态。研究表明：波长差为9 nm的同步荧光光谱中，激发波长282和292 nm处荧光峰分别归属于未参与形成氢键的 Tyr（酪氨酸）残基和参与形成氢键的Tyr残基。对升温过程同步荧光数据进行二维相关分析，得两荧光值对温度的响应顺序，进而推测得到：当温度低于30℃时，0．2 mg·mL－1溶液中出现了胶原分子间形成 Tyr 残基参与的氢键的趋势。0．4和1．6 mg·mL－1的溶液中原有聚集体可能发生进一步聚集，形成疏水微区。当逐步接近胶原变性温度（36～38℃）时，推测0．4和1．6 mg·mL－1胶原溶液中的疏水微区和聚集体有被破坏的趋势，而0．2 mg·mL－1胶原溶液保持分子间形成氢键的趋势。超过胶原变性温度时，各浓度溶液中胶原分子三股螺旋结构发生松散。当超过45℃时，胶原分子三股螺旋结构松散的趋势更为明显。
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