Lee J M, Pereira C A, Abdulla D, Naimark W A, Crawford I
Centre for Biomaterials, University of Toronto, Ontario, Canada.
Med Eng Phys. 1995 Mar;17(2):115-21. doi: 10.1016/1350-4533(95)91882-h.
The temperature at which collagen denatures from a triple helix to a random coil structure is a useful measure of the degree of crosslinking. A new multi-sample denaturation temperature tester (DTT) has been constructed for rapid determination of the collagen denaturation temperature of natural tissues and collagenous biomaterials. To validate the system, the denaturation temperatures measured for the DTT are compared with results from differential scanning calorimetry (DSC). Data are presented for bovine pericardium in three states with denaturation temperatures ranging from 68 to 85 degrees C: fresh, or crosslinked with glutaraldehyde or the epoxide reagent Denacol EX-512 poly (glycidyl ether). Denaturation temperatures measured by DTT were not significantly different from those measured by differential scanning calorimetry (DSC); however, DSC onset systematically occurred at a slightly lower temperature than that measured by DTT. This result, seen only for fresh tissue is in agreement with earlier experiments using hydrothermal isometric tension (HIT) testing. By contrast, DTT and DSC onset were identical for the exogenously crosslinked materials. Since the measured transition temperature was independent of initial load, this variable may be chosen to yield sharper force-temperature transitions with a given sample geometry. This instrument allows accurate assessment of collagen denaturation temperatures for multiple samples in a fraction of the time required by other methods.
胶原蛋白从三螺旋结构变性为无规卷曲结构的温度是交联程度的一个有用度量。已构建一种新型多样品变性温度测试仪（DTT），用于快速测定天然组织和胶原生物材料的胶原蛋白变性温度。为验证该系统，将DTT测得的变性温度与差示扫描量热法（DSC）的结果进行比较。给出了处于三种状态的牛心包的数据，其变性温度范围为68至85摄氏度：新鲜的、用戊二醛交联的或用环氧化试剂Denacol EX - 512聚（缩水甘油醚）交联的。DTT测得的变性温度与差示扫描量热法（DSC）测得的结果无显著差异；然而，DSC起始温度系统地略低于DTT测得的温度。仅在新鲜组织中观察到的这一结果与早期使用水热等长张力（HIT）测试的实验一致。相比之下，对于外源性交联材料，DTT和DSC起始温度相同。由于测得的转变温度与初始负荷无关，对于给定的样品几何形状，可以选择该变量以产生更尖锐的力 - 温度转变。该仪器能够在其他方法所需时间的一小部分内准确评估多个样品的胶原蛋白变性温度。
