Chinese Journal of Magnetic Resonance >
Distortionless Quantitative 13C DEPT++ Experiment
Received date: 2014-04-25
Revised date: 2015-01-12
Online published: 2015-03-05
Supported by
国家重大科学仪器设备开发专项资助项目(2011YQ120035)．
Polarization transfer 13C NMR techniques, such as DEPT and its modified versions (i.e., DEPT++, Q-DEPT and Q-DEPT+), are frequently used in the analysis of complex mixture, given its high sensitivity and resolution. However, the practical use of quantitative DEPT experiments are often hampered by spectral distortions, which makes accurate quantification difficult. In this study, we incorporated elements of the Q-DEPT sequence into the DEPT++ pulse sequence, with the aim to eliminate spectral distortions in Q-DEPT+. The polarization transfer mechanisms underlying DEPT++ were analyzed. It was
found that it is possible to obtain distortionless spectrum in quantitative DEPT++ experiment simply by calibrating the flip angle of the read pulse.
Key words： 13C NMR; Q-DEPT++; DEPT; polarization transfer; quantification
LI Yun-yan1 , 2 , SUN Peng1 , 2 , LIU Mai-li1 , ZHANG Xu1* , LIU Chao-yang1 . Distortionless Quantitative 13C DEPT++ Experiment[J]. Chinese Journal of Magnetic Resonance, 2015 , 32(1) : 51 -58 . DOI: 10.11938/cjmr20150106
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