Measurement of homonuclear proton couplings based on cross-peak nulling in CT-COSY.
Measurement of homonuclear proton couplings based on cross-peak nulling in CT-COSY.
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DOI：
10.1006/jmre.2001.2358
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发表时间：
2001-08
影响因子：
2.2
通讯作者：
Zhengrong Wu;A. Bax
中科院分区：
文献类型：
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作者：
Zhengrong Wu;A. Bax
本文描述了一种方法，在该方法中，1H-1H标量和偶极耦合从一系列恒定时间（CT）COSY谱中的交叉峰零化条件获得，作为CT周期持续时间的函数。该方法最适合测量5-20 Hz范围内的1H-1H耦合。然而，它示出，结果可以是敏感的交叉相关的弛豫效应。此外，由强耦合引起的伪共振在CT-COSY光谱中可以是相当明显的，即使当/J（AB）/（deltaA-deltaB）/<0.1时。实验证明的DNA dodecamer d（CGCGAATTCGCG）2，无论是在各向同性溶液中，并在液晶相。
A method in which 1H-1H scalar and dipolar couplings are obtained from the cross-peak nulling condition in a series of constant-time (CT) COSY spectra, as a function of the duration of the CT period, is described. The method is best suited for measurement of 1H-1H couplings in the range 5-20 Hz. It is shown, however, that results can be sensitive to cross-correlated relaxation effects. Also, artifactual resonances, resulting from strong coupling, can be quite pronounced in CT-COSY spectra, even when /J(AB)/(deltaA-deltaB)/<0.1. The experiments are demonstrated for the DNA dodecamer d(CGCGAATTCGCG)2, both in isotropic solution and in a liquid crystalline phase.