Complex homogeneous and heterogeneous fluorescence anisotropy decays: enhancing analysis accuracy.
Complex homogeneous and heterogeneous fluorescence anisotropy decays: enhancing analysis accuracy.
复制标题
复杂的均质和异质荧光各向异性衰减：提高分析精度。
DOI：
10.1016/s0006-3495(01)75827-4
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发表时间：
2001
影响因子：
3.4
通讯作者：
Prendergast,FG
中科院分区：
文献类型：
--
作者：
Bajzer,Z;Moncrieffe,MC;Penzar,I;Prendergast,FG
在生物大分子中，荧光团通常表现出多个去极化运动，需要多个寿命和旋转弛豫时间来定义荧光强度和各向异性衰减。时间相关的单光子计数数据的相关分析变得不确定，由于众多的衰减参数和数值灵敏度的仪器响应函数（IRF）通过离散化的积分去卷积。通过使用模拟，我们表明，改进的离散化的基础上的二次和三次局部近似的IRF产生更准确的估计短的旋转弛豫时间和寿命比常用的Grinvald-Steinberg离散化，这反过来又出现更可靠的比两个离散化的基础上的线性局部近似的IRF。此外，我们的模拟表明，立方近似是最有利的区分复杂的非均匀和均匀的各向异性衰减。我们发现，在三种不同的信息标准，赤池信息标准是最适合检测旋转弛豫时间的异质性。它是能够检测异质性，即使各向异性衰减出现均匀的统计误差估计。
In biological macromolecules, fluorophores often exhibit multiple depolarizing motions that require multiple lifetimes and rotational relaxation times to define fluorescence intensity and anisotropy decays. The related analysis of time-correlated single-photon counting data becomes uncertain due to the multitude of decay parameters and numerical sensitivity to deconvolution of the instrument response function (IRF) via discretization of integrals. By using simulations we show that improved discretizations based on quadratic and cubic local approximations of the IRF yield more accurate estimation of short rotational relaxation times and lifetimes than the commonly used Grinvald-Steinberg discretization, which in turn appears more reliable than two discretizations based on linear local approximations of the IRF. In addition, our simulation suggests that cubic approximation is the most advantageous in discriminating complex heterogeneous and homogeneous anisotropy decay. We show that among three different information criteria, the Akaike information criterion is best suited for detection of heterogeneity in rotational relaxation times. It is capable of detecting heterogeneity even when anisotropy decay appears homogeneous within statistical errors of estimation.