Linear and nonlinear magneto-optics of ferritin.
Linear and nonlinear magneto-optics of ferritin.
复制标题
铁蛋白的线性和非线性磁光。
DOI：
10.1063/1.3159844
复制
发表时间：
2009
期刊：
影响因子：
--
通讯作者：
Andrzej Dobek
中科院分区：
文献类型：
--
作者：
M. Pankowska;Andrzej Dobek
在室温下，对负载有 0、90、100、500、700 和 1500 个 Fe 原子/分子的脱铁铁蛋白/铁蛋白的 100 mM NaCl 溶液进行瑞利光散射和 Cotton-Mouton (CM) 效应的测量。由于铁蛋白大分子呈球形，因此不应表现出磁各向异性；然而，在溶液中，它显示出感应磁双折射（CM 效应）和散射光成分强度的变化。新获得的数据支持了先前报道的结论，表明磁场在铁蛋白中引起的线性光学极化率的变形和该场引起的磁偶极矩的方向是观察到的磁光现象的主要来源。然而，还发现永磁偶极矩的方向对这两种效应都有贡献。磁场引起的光散射变化和共模效应理论上取决于线性磁光极化率 chi、非线性磁光极化率 eta 以及大分子永磁偶极矩值的平方 mu(2)。基于描述这两种效应的理论和实验数据，估计了线性磁光极化率分量的各向异性值、线性光学极化率及其各向异性、非线性磁光极化率及其各向异性的值。还发现了铁蛋白大分子的磁偶极矩。有趣的是，并非铁蛋白中的所有铁原子都处于超顺磁性状态，其中一些铁原子以抗磁性形式出现。
Measurements of Rayleigh light scattering and Cotton-Mouton (CM) effect are carried out at room temperature for 100 mM NaCl solutions of apoferritin/ferritin loaded with 0, 90, 100, 500, 700, and 1500 Fe atoms/molecule. Because of the spherical shape, ferritin macromolecule should not manifest magnetic anisotropy; however, in solution it shows the induced magnetic birefringence (CM effect) and changes in intensity of the scattered light components. The newly obtained data support the previously reported conclusions indicating that the deformation of linear optical polarizability induced in the ferritin by a magnetic field and the orientation of the induced magnetic dipole moment by this field are the main sources of the magneto-optical phenomena observed. Nevertheless, it is also found that the orientation of the permanent magnetic dipole moment contributes to both effects. The magnetic field induced changes in the light scattering and the CM effect theoretically depend on the linear magneto-optical polarizability, chi, on the nonlinear magneto-optical polarizability, eta, and square of the permanent magnetic dipole moment value of the macromolecule, mu(2). On the basis of the theory describing both effects as well as the experimental data, the values of the anisotropy of linear magneto-optical polarizabilities components, the values of the linear optical polarizability and its anisotropy, nonlinear magneto-optical polarizability and its anisotropy, are estimated. Also the magnetic dipole moment of the ferritin macromolecule is found. Interestingly, not all iron atoms in the ferritin are indicated to be in the superparamagnetic state, some of them occur in the diamagnetic form.
DOI：
--
发表时间：
1982
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Chasteen,ND;Theil,EC
通讯作者：
Theil,EC
影响因子：
3.4
作者：
Petsev, DN;Thomas, BR;Vekilov, PG
通讯作者：
Vekilov, PG