CAJ | 학술논문

具有定量特征的极化转移13C NMR 因检测灵敏度和分辨率高而常用于有机物的NMR定量分析，比如Q-DEPT、Q-DEPT+等。但是，DEPT检测本身存在相位和多重峰畸变问题，可能造成复杂样品的定量测定困难。由于DEPT++技术能够有效地消除上述畸变，该文尝试将 Q-DEPT+方法的定量技术扩展到 DEPT++中，以消除谱峰畸变对于定量的影响。首先，利用积算符对DEPT++的极化转移机制进行了系统理论分析，结果发现目前标准仪器和文献中关于DEPT++可观测算符的表达式中存在符号错误，实验结果进一步证实了我们的猜测；进而采用Q-DEPT+技术中所采用的多极化转移时间和读出脉冲技术，将DEPT++用于定量测定。结果表明所建立的Q-DEPT++方法能够有效地消除谱畸变问题。
구유정량특정적겁화전이13C NMR 인검측령민도화분변솔고이상용우유궤물적NMR정량분석，비여Q-DEPT、Q-DEPT+등。단시，DEPT검측본신존재상위화다중봉기변문제，가능조성복잡양품적정량측정곤난。유우DEPT++기술능구유효지소제상술기변，해문상시장 Q-DEPT+방법적정량기술확전도 DEPT++중，이소제보봉기변대우정량적영향。수선，이용적산부대DEPT++적겁화전이궤제진행료계통이론분석，결과발현목전표준의기화문헌중관우DEPT++가관측산부적표체식중존재부호착오，실험결과진일보증실료아문적시측；진이채용Q-DEPT+기술중소채용적다겁화전이시간화독출맥충기술，장DEPT++용우정량측정。결과표명소건립적Q-DEPT++방법능구유효지소제보기변문제。
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.