Nuclear magnetic resonance(NMR)spectroscopy is a powerful tool for analyzing molecular structure and composition.However,traditional NMR experiments suffer from long acquisition times,especially in multidimensional NM...Nuclear magnetic resonance(NMR)spectroscopy is a powerful tool for analyzing molecular structure and composition.However,traditional NMR experiments suffer from long acquisition times,especially in multidimensional NMR spectroscopy.This problem,to some extent,limits broader applications of NMR techniques.Various methods have been proposed to accelerate sampling,including non-uniform sampling(NUS),multi-FID acquisition(MFA),Hadamard encoding,Fourier encoding,spatial encoding Ultrafast 2D NMR(UF2DNMR),and so on.The review focuses on rapid sampling methods developed in contemporary China,introducing their fundamental principles and applications while discussing their respective advantages and disadvantages.展开更多
In the past few years,efforts have been made to extend the sensitivity of surface nuclear magnetic resonance(SNMR)to short relaxation times,typical for strongly bound water,which,for example,occurs in partially satura...In the past few years,efforts have been made to extend the sensitivity of surface nuclear magnetic resonance(SNMR)to short relaxation times,typical for strongly bound water,which,for example,occurs in partially saturated soils.The two limiting factors for the sensitivity are the dead time after the excitation pulse and the duration of the pulse itself.To enable short pulses,while also achieving proper depths of investigation,high pulse amplitudes are needed.This makes it necessary to consider the Bloch-Siegert effect,i.e.the counter-rotating component and the parallel component of the excitation field have significant influence on the excitation.If an untuned transmitter circuit is used,the pulse shape will also be non-sinusoidal.In this paper,we demonstrate that this influences SNMR measurements with short pulses in two ways:On one hand,the pulse shape influences the phase of the fundamental frequency oscillation.On the other,at very high pulse amplitudes,other frequency components of the excitation field start to influence the excitation.The behavior of the macroscopic magnetizations in the subsurface during the pulse is simulated by solving the Bloch equations,using the pulse shape as an input.Since these calculations are computational expensive,we propose a lookup scheme that allows a time efficient modeling of the obtained SNMR data.展开更多
Coenzyme Q10 and vitamin E are among the most widely consumed nutritional supplements in China owing to their antioxidant and other health-promoting properties.This study aimed to establish an accurate and efficient a...Coenzyme Q10 and vitamin E are among the most widely consumed nutritional supplements in China owing to their antioxidant and other health-promoting properties.This study aimed to establish an accurate and efficient analytical method for the simultaneous determination of these two compounds in commercial softgel capsules,which is essential for rigorous quality control.Herein,a proton nuclear magnetic resonance(1H NMR)method was developed and validated using coumarin as an internal standard.Characteristic signals at 3.997 ppm for coenzyme Q10 and 2.621 ppm for vitamin E were selected for quantification.The method demonstrated excellent performance in terms of precision(relative standard deviation<2%),specificity(resolution>1.5),and stability(24-h variation<3%).The validation results complied with the China Food and Drug Administration guidelines,demonstrating high accuracy.Application to products from four different manufacturers showed compound contents ranging from 98.2%to 102.4%of label amounts.These findings support^(1)H NMR spectroscopy as a rapid,precise,and reliable approach for the simultaneous quality assessment of coenzyme Q10 and vitamin E formulations.展开更多
Nuclear magnetic resonance(NMR)spectroscopy is an indispensable tool to probe weak protein-ligand interactions,which are key to the hit identification and hit-to-lead evolution in fragment-based drug discovery(FBDD).T...Nuclear magnetic resonance(NMR)spectroscopy is an indispensable tool to probe weak protein-ligand interactions,which are key to the hit identification and hit-to-lead evolution in fragment-based drug discovery(FBDD).The integration of NMR technology in FBDD has facilitated the development of a diverse array of candidate compounds and FDAapproved drugs.Here,we summarized the rapid advancement and application of NMR techniques in contemporary China,which serves as a catalyst for the ongoing prosperousness of fragment-derived inhibitors against various targets.展开更多
WITHDRAWAL:Zhang,J.J.,Guo,Y.Q.,Qin,Z.Y.,Wei,C.T.,Hu,Q.H.,Vandeginste,V.,Miao,H.Y.,Yao,P.,and Zhang,P.F.,“Predicting Irreducible Water Saturation of Unconventional Reservoirs by Using NMR T2 Spectra:Methods of Morphol...WITHDRAWAL:Zhang,J.J.,Guo,Y.Q.,Qin,Z.Y.,Wei,C.T.,Hu,Q.H.,Vandeginste,V.,Miao,H.Y.,Yao,P.,and Zhang,P.F.,“Predicting Irreducible Water Saturation of Unconventional Reservoirs by Using NMR T2 Spectra:Methods of Morphological Division and Fractal Models”,Acta Geologica Sinica-English Edition(Accepted Article):https://doi.org/10.1111/1755-6724.15094.展开更多
基金financially supported by the National Natural Science Foundation of China(grant numbers 22174118,12411530077,and 22374124).
文摘Nuclear magnetic resonance(NMR)spectroscopy is a powerful tool for analyzing molecular structure and composition.However,traditional NMR experiments suffer from long acquisition times,especially in multidimensional NMR spectroscopy.This problem,to some extent,limits broader applications of NMR techniques.Various methods have been proposed to accelerate sampling,including non-uniform sampling(NUS),multi-FID acquisition(MFA),Hadamard encoding,Fourier encoding,spatial encoding Ultrafast 2D NMR(UF2DNMR),and so on.The review focuses on rapid sampling methods developed in contemporary China,introducing their fundamental principles and applications while discussing their respective advantages and disadvantages.
基金funded by the German Research Foundation(Deutsche Forschungsgemeinschaft-DFG)under grant MU 3318/8-1.
文摘In the past few years,efforts have been made to extend the sensitivity of surface nuclear magnetic resonance(SNMR)to short relaxation times,typical for strongly bound water,which,for example,occurs in partially saturated soils.The two limiting factors for the sensitivity are the dead time after the excitation pulse and the duration of the pulse itself.To enable short pulses,while also achieving proper depths of investigation,high pulse amplitudes are needed.This makes it necessary to consider the Bloch-Siegert effect,i.e.the counter-rotating component and the parallel component of the excitation field have significant influence on the excitation.If an untuned transmitter circuit is used,the pulse shape will also be non-sinusoidal.In this paper,we demonstrate that this influences SNMR measurements with short pulses in two ways:On one hand,the pulse shape influences the phase of the fundamental frequency oscillation.On the other,at very high pulse amplitudes,other frequency components of the excitation field start to influence the excitation.The behavior of the macroscopic magnetizations in the subsurface during the pulse is simulated by solving the Bloch equations,using the pulse shape as an input.Since these calculations are computational expensive,we propose a lookup scheme that allows a time efficient modeling of the obtained SNMR data.
基金supported by the Open Research Fund Program of the Shandong Provincial Key Laboratory of Glycoscience and Glycotechnology(Ocean University of China)。
文摘Coenzyme Q10 and vitamin E are among the most widely consumed nutritional supplements in China owing to their antioxidant and other health-promoting properties.This study aimed to establish an accurate and efficient analytical method for the simultaneous determination of these two compounds in commercial softgel capsules,which is essential for rigorous quality control.Herein,a proton nuclear magnetic resonance(1H NMR)method was developed and validated using coumarin as an internal standard.Characteristic signals at 3.997 ppm for coenzyme Q10 and 2.621 ppm for vitamin E were selected for quantification.The method demonstrated excellent performance in terms of precision(relative standard deviation<2%),specificity(resolution>1.5),and stability(24-h variation<3%).The validation results complied with the China Food and Drug Administration guidelines,demonstrating high accuracy.Application to products from four different manufacturers showed compound contents ranging from 98.2%to 102.4%of label amounts.These findings support^(1)H NMR spectroscopy as a rapid,precise,and reliable approach for the simultaneous quality assessment of coenzyme Q10 and vitamin E formulations.
基金the National Key R&D Program of China(2024YFA1306200)National Natural Science Foundation of China(22377119)+2 种基金Anhui Provincial Natural Science Foundation(2208085MC50)USTC Research Funds of the Double First-Class Initiative(YD9100002028,YD9100002036)Research Funds of Center for Advanced Interdisciplinary Science and Biomedicine of IHM(QYPY20220008)for their financial support.
文摘Nuclear magnetic resonance(NMR)spectroscopy is an indispensable tool to probe weak protein-ligand interactions,which are key to the hit identification and hit-to-lead evolution in fragment-based drug discovery(FBDD).The integration of NMR technology in FBDD has facilitated the development of a diverse array of candidate compounds and FDAapproved drugs.Here,we summarized the rapid advancement and application of NMR techniques in contemporary China,which serves as a catalyst for the ongoing prosperousness of fragment-derived inhibitors against various targets.
文摘WITHDRAWAL:Zhang,J.J.,Guo,Y.Q.,Qin,Z.Y.,Wei,C.T.,Hu,Q.H.,Vandeginste,V.,Miao,H.Y.,Yao,P.,and Zhang,P.F.,“Predicting Irreducible Water Saturation of Unconventional Reservoirs by Using NMR T2 Spectra:Methods of Morphological Division and Fractal Models”,Acta Geologica Sinica-English Edition(Accepted Article):https://doi.org/10.1111/1755-6724.15094.
