Rotational Diffusion of Membrane Proteins Optical Methods

摘要: Optical methods for measurement of Brownian rotational diffusion depend upon the use linearly polarized light. Furthermore, molecule under study must be capable being photoexcited to some state which can detected separately from non-excited state. The measurements rotation photoselection, briefly works as follows. An isotropic (random) array molecules is partially converted excited by a flash light appropriate wavelength. Because relationship between molecular orientation and probability absorbing light, population anisotropic. This anisotropy optically in various ways: polarization emitted state, e.g., prompt delayed fluorescence phosphorescence, absorption bands, i.e., linear dichroism, or remaining also anisotropic ground-state bands. Rotational will abolish flash-established time-dependent fashion. Conversely, decay flash-induced enable coefficients calculated. These concepts were established more than half century ago (Perrin, 1926, 1929) have been extensively reviewed (Albrecht, 1961, 1970).