Pietrucha K, Marzec E
Institute of Polimer and Dye Technology, Technical University of Łódź, Stefanowskiego 12/16, 90-924 Łódź, Poland.
Biophys Chem. 2005 Oct 22;118(1):51-6. doi: 10.1016/j.bpc.2005.07.006.
Dielectric spectroscopy has been applied to study the decomposition process of unmodified collagen and chondroitin sulfate (CS)- and hyaluronic acid (HA)-modified collagen. Measurements were performed over the frequency range from 10 Hz to 100 kHz and at temperatures from 22 to 260 degrees C. According to the Kramers-Kronig relationship a dispersion is apparent in both epsilon' and epsilon'' for the three materials below 140 degrees C and at higher temperatures as a broad peak around 220-230 degrees C, respectively. The values of epsilon' and epsilon'' at the same temperature for constant frequency are higher in HA-modified collagen than in the unmodified collagen. However, small differences are shown in these parameters between CS-modified collagen and unmodified collagen. The observed dispersion around 220-230 degrees C corresponds to the decomposition of unmodified and CS- and HA-modified collagen. Power-low responses are observed for the frequency dependence of ac conductivity for unmodified and modified collagen. The behaviour observed for temperature dependencies of the exponent n for the three materials is considered to be related to the proton polarization and conduction processes.
介电谱已被用于研究未改性胶原蛋白以及硫酸软骨素（CS）和透明质酸（HA）改性胶原蛋白的分解过程。测量在10 Hz至100 kHz的频率范围内以及22至260摄氏度的温度下进行。根据克拉默斯 - 克勒尼希关系，对于这三种材料，在140摄氏度以下，ε'和ε''中均出现色散，而在较高温度下，分别在220 - 230摄氏度左右出现一个宽峰。在相同温度和恒定频率下，HA改性胶原蛋白的ε'和ε''值高于未改性胶原蛋白。然而，CS改性胶原蛋白和未改性胶原蛋白在这些参数上显示出微小差异。在220 - 230摄氏度左右观察到的色散对应于未改性以及CS和HA改性胶原蛋白的分解。观察到未改性和改性胶原蛋白的交流电导率对频率的幂律响应。这三种材料的指数n对温度的依赖性所观察到的行为被认为与质子极化和传导过程有关。
