Marzec E, Pietrucha K
Department of Biophysics, Poznań University of Medical Sciences, Poznań, Poland.
Biophys Chem. 2008 Feb;132(2-3):89-96. doi: 10.1016/j.bpc.2007.10.012. Epub 2007 Nov 9.
This paper reports on the effect of different methods of collagen cross-linking on its dielectric properties. In order to obtain collagen-hyaluronic acid (HA) scaffolds, collagen was first dehydrated by a combination of thermal and vacuum drying (DHT) and then treated with the chemical reagent carbodiimide (EDC/NHS) for final cross-linking. The measurements of the relative permittivity epsilon' and the dielectric loss epsilon'' for all materials were carried over the frequency range of 10 Hz-100 kHz and at temperatures from 22 to 260 degrees C. The results for these samples reveal distinct relaxation processes at low temperatures, below 140 degrees C and at higher temperatures as broad peak around 230 degrees C. The first and second relaxation are associated with changes in the secondary structure of collagen accompanied by the release of water and with the denaturation of dry collagen, respectively. The influence of cross-linking on the permittivity of collagen is significant over the entire temperature range.
本文报道了不同胶原蛋白交联方法对其介电性能的影响。为了获得胶原蛋白-透明质酸（HA）支架，首先通过热干燥和真空干燥相结合的方法（DHT）对胶原蛋白进行脱水处理，然后用化学试剂碳二亚胺（EDC/NHS）进行最终交联。对所有材料的相对介电常数ε'和介电损耗ε''的测量在10 Hz - 100 kHz的频率范围内以及22至260摄氏度的温度下进行。这些样品的结果显示，在低于140摄氏度的低温下以及在230摄氏度左右的较宽峰值处的较高温度下存在明显的弛豫过程。第一次和第二次弛豫分别与胶原蛋白二级结构的变化（伴随着水的释放）以及干燥胶原蛋白的变性有关。在整个温度范围内，交联对胶原蛋白介电常数的影响都很显著。
