TY - JOUR
T1 - TmDOTA as versatile thermometer compound for solid-state NMR of hydrated lipid bilayer membranes
AU - Umegawa, Yuichi
AU - Tanaka, Yuya
AU - Nobuaki, Matsumori
AU - Murata, Michio
N1 - Funding Information:
We thank Drs F. Satou, S. Hanashima, and H. Tsuchikawa in our laboratory for discussion on synthesis of labeled compounds and Drs S. Matsuoka, Y. Todokoro, N. Inazumi, and M. Kinoshita in our department for information on solid-state NMR and DSC measurements. This work was supported by Japanese Society of Technology ERATO, Lipid Active Structure Project. This work was supported in part by JSPS KAKENHI (Japan) grants 25750383 (Y.U.) and 25242073 (M.M.).
Publisher Copyright:
Copyright © 2015 John Wiley & Sons, Ltd.
PY - 2016/3/1
Y1 - 2016/3/1
N2 - Recent advances in solid-state nuclear magnetic resonance (NMR) techniques, such as magic angle spinning and high-power decoupling, have dramatically increased the sensitivity and resolution of NMR. However, these NMR techniques generate extra heat, causing a temperature difference between the sample in the rotor and the variable temperature gas. This extra heating is a particularly crucial problem for hydrated lipid membrane samples. Thus, to develop an NMR thermometer that is suitable for hydrated lipid samples, thulium-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetate (TmDOTA) was synthesized and labeled with 13C (i.e., 13C-TmDOTA) to increase the NMR sensitivity. The complex was mixed with a hydrated lipid membrane, and the system was subjected to solid-state NMR and differential scanning calorimetric analyses. The physical properties of the lipid bilayer and the quality of the NMR spectra of the membrane were negligibly affected by the presence of 13C-TmDOTA, and the 13C chemical shift of the complex exhibited a large-temperature dependence. The results demonstrated that 13C-TmDOTA could be successfully used as a thermometer to accurately monitor temperature changes induced by 1H decoupling pulses and/or by magic angle spinning and the temperature distribution of the sample inside the rotor. Thus, 13C-TmDOTA was shown to be a versatile thermometer for hydrated lipid assemblies.
AB - Recent advances in solid-state nuclear magnetic resonance (NMR) techniques, such as magic angle spinning and high-power decoupling, have dramatically increased the sensitivity and resolution of NMR. However, these NMR techniques generate extra heat, causing a temperature difference between the sample in the rotor and the variable temperature gas. This extra heating is a particularly crucial problem for hydrated lipid membrane samples. Thus, to develop an NMR thermometer that is suitable for hydrated lipid samples, thulium-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetate (TmDOTA) was synthesized and labeled with 13C (i.e., 13C-TmDOTA) to increase the NMR sensitivity. The complex was mixed with a hydrated lipid membrane, and the system was subjected to solid-state NMR and differential scanning calorimetric analyses. The physical properties of the lipid bilayer and the quality of the NMR spectra of the membrane were negligibly affected by the presence of 13C-TmDOTA, and the 13C chemical shift of the complex exhibited a large-temperature dependence. The results demonstrated that 13C-TmDOTA could be successfully used as a thermometer to accurately monitor temperature changes induced by 1H decoupling pulses and/or by magic angle spinning and the temperature distribution of the sample inside the rotor. Thus, 13C-TmDOTA was shown to be a versatile thermometer for hydrated lipid assemblies.
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U2 - 10.1002/mrc.4371
DO - 10.1002/mrc.4371
M3 - Article
AN - SCOPUS:84958750306
SN - 0749-1581
VL - 54
SP - 227
EP - 233
JO - Magnetic Resonance in Chemistry
JF - Magnetic Resonance in Chemistry
IS - 3
ER -