Electric birefringence of poly‐L‐lysine hydrobromide in methanol–water mixtures and helix–coil transition induced by high electric fields
Electric birefringence of poly‐L‐lysine hydrobromide in methanol–water mixtures and helix–coil transition induced by high electric fields
复制标题
聚-L-赖氨酸氢溴酸盐在甲醇-水混合物中的电双折射和高电场诱导的螺旋-线圈转变
DOI：
10.1002/bip.1973.360121204
复制
发表时间：
1973
期刊：
影响因子：
2.9
通讯作者：
K. Yoshioka
中科院分区：
文献类型：
--
作者：
K. Kikuchi;K. Yoshioka
利用矩形脉冲技术测量了聚L -氢溴化赖氨酸在甲醇-水混合物中在25°C、宽场强范围内的电双折射。在87和90 vol %甲醇之间，观察到比Kerr常数的突变，对应于溶剂诱导的螺旋线圈转变。在随机螺旋形中，比克尔常数随稀释量的增加而迅速增加，而在螺旋形中则缓慢增加。在不同浓度下，对于螺旋形和线圈形构象，电场强度的依赖关系可以用一个共同的取向函数来描述，该函数类似于永久偶极矩取向情况下的理论函数。这是根据离子-大气极化的饱和来解释的。螺旋形的光学各向异性比螺旋形的大得多。
The electric birefringence of poly‐L‐lysine hydrobromide in methanol–water mixtures has been measured at 25 °C over a wide range of field strengths by use of the rectangular pulse technique. An abrupt change in the specific Kerr constant was observed between 87 and 90 vol % methanol, corresponding to the solvent‐induced helix–coil transition. The specific Kerr constant increased rapidly with dilution in the random coil form, and more slowly in the helical conformation. The field strength dependence of the bire fringence at various concentrations, for both the helical and coil conformations, can be described by a common orientation function, which resembles the theoretical one for the case of permanent dipole moment orientation. This is interpreted in terms of the saturation of ion–atmosphere polarization. The optical anisotropy for the helical conformation was much larger than that for the coil form.