生物固体核磁共振中样品发热的研究进展

Heating of Biological Samples in Studies of MAS Solid-State NMR

近年来,固体核磁共振被广泛应用于膜蛋白、纤维化蛋白等体系的结构和功能研究.在固体核磁共振实验中,快速魔角旋转或高功率射频场照射等实验条件将导致样品发热.生物样品发热能导致严重的后果,例如样品温度的快速升高,信号分辨率、信噪比的降低,发热严重时甚至导致样品的不可逆损坏.近年来,人们对样品发热问题进行了一些研究,发现通过优化样品制备条件或固体核磁共振实验条件,以及改进探头设计等手段,可以在一定程度上减轻样品发热.该文主要综述了生物固体核磁共振研究中导致样品发热的原因和减轻样品发热的方法.

Magic-angle-spinning （MAS） solid-state NMR studies of biomolecules involve application of rapid sample rotation and radiofrequency pulsing, both of which can increase the sample temperature significantly, causing distorted spectra, sample dehydration and even sample degradation. In this review, the mechanisms leading to bio-sample heating in MAS solid-state NMR experiments are first introduced. The importance of sample temperature monitoring is then emphasized. Finally, we present the methods that can be used to to alleviate the problem, including optimization of sample preparation, selecting optimal NMR parameters, and improving NMR spectrometer hardware such as the probes.