Name: nmr spectroscopy as a robust tool for the rapid evaluation of the lipid profile of fish oil supplements
Uploaded: 2017-05-01T11:45:00
Description: Watch this Scientific Journal Video about NMR Spectroscopy as a Robust Tool for the Rapid Evaluation of the Lipid Profile of Fish Oil Supplements at JoVE.com

这项工作是由俄亥俄州立大学食品卫生发现主题和食品科学与技术在美国俄亥俄州立大学的部门支持。作者要感谢俄亥俄州立大学的NMR设施和宾夕法尼亚州立大学的核磁共振设备。

1. NMR样品制备注意：注意，使用前请咨询所有相关的材料安全数据表（MSDS）。在样品制备中使用的氘代氯仿（CDCL 3）是有毒的。进行样品制备，包括使用通风橱和个人保护设备的时，请使用所有的适当的安全实践（安全眼镜，手套，实验室外套，全长裤，封闭趾鞋）。 <ol><li> 1个 H和13个 C样品的制备 <ol><li>用注射器从膳食胶囊提取鱼油?...

<ol>
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Diet Assoc. 104 (6), 942-950 (2004).</li><li>Dwyer, J. T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Progress+in+developing+analytical+and+label-based+dietary+supplement+databases+at+the+NIH+office+of+dietary+supplements.">Progress in developing analytical and label-based dietary supplement databases at the NIH office of dietary supplements.</a> J. Food Compos. Anal. 21, S83-S93 (2008).</li><li>Monakhova, Y. B., Ruge, I., Kuballa, T., Lerch, C., Lachenmeier, D. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rapid+determination+of+coenzyme+Q10+in+food+supplements+using+1H+NMR+spectroscopy.">Rapid determination of coenzyme Q10 in food supplements using 1H NMR spectroscopy.</a> Int. J. Vitam. Nutr. Res. 83 (1), 67-72 (2013).</li><li>Monakhova, Y. B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Standardless+1H+NMR+determination+of+pharmacologically+active+substances+in+dietary+supplements+and+medicines+that+have+been+illegally+traded+over+the+internet.">Standardless 1H NMR determination of pharmacologically active substances in dietary supplements and medicines that have been illegally traded over the internet.</a> Drug Test. Anal. 5 (6), 400-411 (2013).</li><li>Berger, S., Braun, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> 200 and more NMR experiments: a practical course. , (2004).</li><li>Knothe, G., Kenar, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Determination+of+the+fatty+acid+profile+by+1H-NMRspectroscopy.">Determination of the fatty acid profile by 1H-NMRspectroscopy.</a> Eur. J. Lipid Sci. Technol. 106, 88-96 (2004).</li><li>Sacchi, R., Medina, J. I., Aubourg, S. P., Paolillo, I. G. L., Addeo, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quantitative+High-Resolution+13C+NMR+Analysis+of+Lipids+Extracted+from+the+White+Muscle+of+Atlantic+Tuna+(Thunnus+alalunga).">Quantitative High-Resolution 13C NMR Analysis of Lipids Extracted from the White Muscle of Atlantic Tuna (Thunnus alalunga).</a> J. Agric. Food Chem. 41 (8), 1247-1253 (1993).</li><li>Dais, P., Misiak, M., Hatzakis, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Analysis+of+marine+dietary+supplements+using+NMR+spectroscopy.">Analysis of marine dietary supplements using NMR spectroscopy.</a> Anal. Methods. 7 (12), 5226-5238 (2015).</li><li>Pickova, J., Dutta, P. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cholesterol+Oxidation+in+Some+Processed+Fish+Products.">Cholesterol Oxidation in Some Processed Fish Products.</a> J. Anal. Oil Chem. Soc. 80 (10), 993-996 (2003).</li><li>Siddiqui, N., Sim, J., Silwood, C. J. L., Toms, H., Iles, R. 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P., Gao, X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Z-restored+spin-echo+13C+1D+spectrum+of+straight+baseline+free+of+hump,+dip+and+roll.">Z-restored spin-echo 13C 1D spectrum of straight baseline free of hump, dip and roll.</a> Magn. Reson. Chem. 46, 432-435 (2008).</li><li>Tengku-Rozaina, T. M., Birch, E. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Positional+distribution+of+fatty+acids+on+hoki+and+tuna+oil+triglycerides+by+pancreatic+lipase+and+13C+NMR+analysis.">Positional distribution of fatty acids on hoki and tuna oil triglycerides by pancreatic lipase and 13C NMR analysis.</a> Eur. J. Lipid Sci. Technol. 116 (3), 272-281 (2014).</li><li>Berry, S. E. 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修改和策略疑难解答 光谱质量 。 NMR信号，从而NMR谱的分辨率的线宽是高度依赖于匀场，这是用于磁场的均匀性的优化的方法。对于常规分析，1D匀场是足够的，并不需要3D匀场，因为它是通过NMR人员定期进行。 D 2 O中（90:10）：如果不是这种情况下，3D匀场必须被分析之前，使用含有0.6毫升氧化氢的样品进行的。为了实现更好更快匀场，样品需要在?...

在饮食Ñ-3脂肪酸的消费已被证明是对几个条件有利如心脏疾病1，2，3，炎性疾病4和糖尿病5。西方饮食被认为是穷人的N-3脂肪酸，因此建议鱼油补充剂的消费，提高n个 -6 / N -3平衡消费者的营养1。尽管鱼油补充剂的消费，最近越来越多，问题仍然是关于安全性，真实性，以及一些产品的质量。鱼油补充剂的快速和准确的成分分析是必不可少的，以正确评估这些商业产品的质量，保证消费者的安全。 鱼油补充评估的最常见方法s为气相色谱法（GC）和红外光谱（IR）。虽然这些都是高度敏感的方法，他们从几个缺点遭受6。 GC分析是因为单独的化合物的分离和衍生化，需要7和分析8,9期间可能发生的脂质氧化耗时（4-8小时）。虽然IR光谱可以是定量，需要一个预测模型，使用偏最小二乘回归（PLSR）构造，但也有例外，其中IR带可以归因于一个单一的化合物10。 PLSR需要大量的样品，从而增加了分析11的时间的分析。出于这个原因，存在的新的分析方法，使大量的鱼油样品的准确，快速分析发展的越来越大的兴趣。组织，如OFFI在健康（NIH）和美国食品和药物管理局（FDA）全国学院膳食补充剂（ODS）的CE与官方分析化学师协会（AOAC）合作开发这些新方法12，13。 一个用于筛选和多组分基质，如膳食补充品的评价最有前途的分析方法，是核磁共振（NMR）光谱14,15。 NMR光谱法有几个优点：它是一种非破坏性的和定量技术，它需要极少的无样品制备，并且其特征在于优良的精确度和再现性。此外，NMR光谱是一种环境友好的方法，因为它仅使用少量的溶剂。 NMR光谱法的主要缺点是其相对低的灵敏度相比其他analytiCAL方法，但是，例如更强的磁场，各种直径的低温探针，先进的数据处理，和通用的脉冲序列和技术在仪表最近的技术进步增加了灵敏度高达nM范围内。虽然核磁共振仪器是成本高，核磁共振波谱仪的长寿命和NMR的许多应用降低了分析的，从长远来看成本。这个详细的视频协议的目的是帮助本领域从业者新避免与1个 H和13个 C NMR光谱分析鱼油补充剂的相关联的缺陷。

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Avance III 850 NMR instrument</td>
			<td>Bruker</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Avance III 500 NMR instrument</td>
			<td>Bruker</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>TCI 5mm probe</td>
			<td>Bruker</td>
			<td></td>
			<td>Helium cooled inverse (proton deetected) NMR probe featuring three independent channels (1H, 13C, 15N)</td>
		</tr>
		<tr>
			<td>BBO prodigy 5mm probe</td>
			<td>Bruker</td>
			<td></td>
			<td>Nitrogen cooled observe (X-nuclei detected) probe, featuring two channels; one for 1H and 19F detectionand one for X-nuclei (covering from 15N to 31P)</td>
		</tr>
		<tr>
			<td>Spinner turbin</td>
			<td>Bruker</td>
			<td></td>
			<td>NMR spinners are made by polymer materials and they have a rubber o-ring to hold the NMR tube securely in place</td>
		</tr>
		<tr>
			<td>Topspin 3.5</td>
			<td>Bruker</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>deuterated chloroform</td>
			<td>Sigma-Aldrich</td>
			<td>&#160;865-49-6</td>
			<td>99.8 atom % D, contains 0.03 TMS</td>
		</tr>
		<tr>
			<td>2,6-Di-tert-butyl-4-methylphenol,</td>
			<td>Sigma-Aldrich</td>
			<td>&#160;128-37-0</td>
			<td>purity &#62;99%</td>
		</tr>
		<tr>
			<td>Fish oil samples</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>NMR tubes</td>
			<td>New Era</td>
			<td>NE-RG5-7</td>
			<td>5mm OD Routine &#8220;R&#8221; Series NMR Sample Tube</td>
		</tr>
		<tr>
			<td>BSMS</td>
			<td>Bruker</td>
			<td></td>
			<td>Bruker Systems Management System; control system device</td>
		</tr>
	</tbody>
</table>

nmr spectroscopy as a robust tool for the rapid evaluation of the lipid profile of fish oil supplements

西方饮食同n-3脂肪酸差，因此建议鱼油补充剂的消费，以增加这些必需营养素的摄入量。这个工作的目的是利用高分辨率1个 H和13利用两个不同的NMR仪器C NMR光谱法证实包封的鱼油补充剂的定性和定量分析;一个500兆赫和850兆赫的仪器。两个质子（1个 H）和碳（13 C）NMR谱可用于定量测定鱼油补充剂的主要成分。在鱼油补充剂脂质的定量是通过适当的NMR信号的积分在相关1D光谱来实现。通过1 H和13 C NMR得到的结果彼此一致，尽管在两个核和两个仪器之间的分辨率和灵敏度的差异。 1 H-NMR报价SA的快速分析相比13 C NMR，作为频谱可被记录在小于1分钟，而相比之下，13点 C NMR分析，它从10分钟持续到一小时。 13 C NMR谱，然而，更加丰富。它可以用于单个脂肪酸更大数量提供定量数据，并可以被用于确定在甘油骨架的脂肪酸的位置分布。两者的核可以提供仅在一个实验中的定量信息，而无需纯化或分离步骤。的磁场的强度主要影响：1个 H NMR谱由于相对于13 C NMR其较低的分辨率，但是，即使是更低的成本NMR仪器可以有效地应用为食品工业和质量控制实验室的标准方法。

1 H和13个 C NMR光谱收集使用两个NMR仪器市售鱼油补充剂; 850 MHz和500 MHz光谱。这些光谱可用于定量测定鱼油的组分，如二十二碳六烯酸（DHA）和二十碳五烯酸（EPA），以及其它化合物，如正 -1酰基链的和营养的重要指标，如正 -6 / N -3比。所述定量可即使不使用内标来进行，然而，定量结果必须表示为相对摩尔百分比。当数据需要以绝对?...

Watch this Scientific Journal Video about NMR Spectroscopy as a Robust Tool for the Rapid Evaluation of the Lipid Profile of Fish Oil Supplements at JoVE.com

NMR Spectroscopy as a Robust Tool for the Rapid Evaluation of the Lipid Profile of Fish Oil Supplements

这里，高分辨率1 H和13 C核磁共振（NMR）光谱被用作包封的鱼油补充剂的定量和定性分析的快速和可靠的工具。

核磁共振作为鱼油补充剂的血脂的快速评价一个强大的工具

The western diet is poor in n-3 fatty acids, therefore the consumption of fish oil supplements is recommended to increase the intake of these essential ...

The overall goal of this method is to determine the lipid profile of fish oil supplements using Nuclear Magnetic Resonance spectroscopy. This method can help answer key questions for lipid analysis such as the lipid contents of fish oil supplements and the positional distribution of various fatty acids on the glycerol skeleton. The main advantage of this technique is that it makes the rapid and robust analysis of several different molecules feasible in one snapshot without using separation and purification steps.To prepare the samples for proton and carbon NMR analysis, first extract 120 microliters, which is around 110 milligrams of fish oil, from a dietary capsule using a syringe and place it in a 4-mL glass vial. Record the weight of the fish oil. Use 500 microliters of a BHT stock solution to dissolve 100 milligrams plus or minus 10 milligrams of fish oil.After dissolving the oil, transfer all of the solution directly into a high quality, five millimeter NMR tube and attach a cap. Analyze the samples within 24 hours of preparing the samples. Insert the NMR tube into a spinner turbine.Place the spinner and the tube on the top of a graded depth gauge and gently push the top of the tube until its bottom part touches the bottom of the gauge. Then place the NMR tube in an open spot of the sample case. Note the slot number the sample is placed in.To load the sample in the NMR instrument, return to the control computer and type SX-number, where number is the slot in the sample case holding the sample. Wait for the deuterium signal of deuterated chloroform to appear on the screen. As soon as the deuterium signal is visible, type lock"on the command line and select deuterated chloroform from the solvents list to lock the sample using its deuterium resonance.Type bsmsdisp"in the command line to ensure spinning is not active. If the spin button is green, click it to deactivate spinning. After typing the command new"to create a new data set, enter a name for the data set in the name tab and the experiment number in the experiment number tab titled EXPNO.Use number one in the process number tab titled PROCNO. Write the title of the experiment in the TITLE tab. In the Experiment tab, hit Select and choose the C13IG parameter file.Then hit Set selected item in editor"and click OK.Type getprosol"in the command line to obtain the standard parameters for the current NMR probe and solvent. Then type the command atma"to perform automatic tuning and to matching of the probe for both carbon and proton nuclei. Next, perform one-dimensional gradient shimming to achieve a highly homogeneous magnetic field and thus optimum line shape for the NMR signals.To do so, use the standard automatic procedure for 1D shimming simply by sequently executing the commands qu topshim 1dfast ss;qu topshim tuneb ss;and qu topshim report"in the command line. After parameter optimization as described in the text protocol, acquire one dimensional carbon NMR spectra. To do so, go to the carbon data set and use an inverse gated decoupled pulse sequence by typing pulprog zgig"in the command line.Type commands on the command line to set up the spectral with nppm, the center of the RF transmitter, the number of scans, the number of dummy scans, the number of data points, and the pulse duration for a ninety degree pulse angle. Type digmod baseopt"in the command line to acquire a spectrum with an improved base line. Then set a relaxation delay of 60 seconds for the 850 megahertz instrument by typing di 60s"in the command line.Set the receiver gain to an appropriate value using the command rga"for automatic calculation of receiver gain. Finally, start the acquisition by typing the pulse acquire command zg"in the command line. To process the data, first type si 64K"in the command line to apply zero filling and set the size of the rail spectrum to 64K.Then set the line broadening parameter to 1.0 hertz by typing lb 1.0"in the command line to apply a waiting function with a line broadening factor of 1.0 hertz prior to 4ea transform. Execute 4ea transformation by typing efp"in the command line. Next perform automatic phase correction by typing the command apk"in the command line.If additional phase adjustments are required to further improve the spectrum, click on the Process tab. Then click on the Adjust Phase icon and the Phase Correction icons for zero order and first order phase correction. While clicking on the zero order and first order phase correction icons, drag the mouse until all of the signals are in positive absorption mode.Apply and save the phase correction values by clicking the Return and Save button to exit the Phase Correction mode. Apply a polynomial forth order function for baseline correction upon integration by typing the command abs n"in the command line. To report chemical shifts in ppm from TMS, zoom in on the TMS signal, then click on the Calibration icon and place the cursor with the red line on top of the NMR signal to be referenced, TMS in this case.To adjust the threshold intensity, use the middle mouse button if needed. Left click and type in 0. When using BHT as an internal standard, integrate the peak at delta 151.45 extending five hertz from each side of the peak.Then set the integral equal to the micromoles of BHT per 0.5 milliliters of the stock solution. Integrate the peaks of interest extending fiver hertz from each side of the peak. If there is a need to focus on a region, click on the highlight icon to deactivate it.Then left click and drag to zoom in on the region. Click on the highlight icon again to make the integration function active and move to the next peak. Left click and drag the cursor through the integral.Click the Return Save Regions button. Shown here is a representative spectrum of the Carbon NMR analysis in the carbonyl carbon region. The NMR signals of EPA and DHA on the sn-1, 3 and sn-2 positions are shown.These signals can be used for the quantitative determination of EPA and DHA. Shown here is a representative spectrum of the proton NMR analysis. The NMR signals of EPA and DHA that can be used for their determination are shown.The proton NMR spectrum is characterized by a narrower spectral width as compared to the carbon NMR spectrum and thus a lower spectral resolution. Once mastered, this technique can be done in less than 30 minutes if it is performed properly. After its development, this technique paved the way for researchers in the field of lipid analysis to rapidly analyze various lipid components that appear in multi-component matrices, such as dietary supplements, vegetable oil, and biofuels.After watching this video, you should have a good understanding of how to apply proton and carbon, NMR spectroscopy for the analysis of the lipid profile of fish oil supplements. Don't forget that working with strong magnetic fields produced by NMR spectrometers can be extremely hazardous to pacemakers and surgical protheses as well as electronic items such as credit cards and watches.

Research

JoVE Journal

Chemistry

Isolation and Chemical Characterization of Lipid A from Gram-negative Bacteria

隔离和脂质A的化学表征革兰氏阴性菌

Lipopolysaccharide (LPS) is the major cell surface molecule of gram-negative bacteria, deposited on the outer leaflet of the outer membrane bilayer. LPS ...

科研

化学

Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR

Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR

Copper (I) binding by metallochaperone transport proteins prevents copper oxidation and release of the toxic ions that may participate in harmful redox ...

Methods to Identify the NMR Resonances of the 13C-Dimethyl N-terminal Amine on Reductively Methylated Proteins

Methods to Identify the NMR Resonances of the 13C-Dimethyl N-terminal Amine on Reductively Methylated Proteins

Nuclear magnetic resonance (NMR) spectroscopy is a proven technique for protein structure and dynamic studies. To study proteins with NMR, stable magnetic ...

HKUST-1 as a Heterogeneous Catalyst for the Synthesis of Vanillin

科大-1作为香兰素的合成的非均相催化剂

Vanillin (4-hydoxy-3-methoxybenzaldehyde) is the main component of the extract of vanilla bean. The natural vanilla scent is a mixture of approximately ...

Spin Saturation Transfer Difference NMR (SSTD NMR): A New Tool to Obtain Kinetic Parameters of Chemical Exchange Processes

Spin Saturation Transfer Difference NMR SSTD NMR: A New Tool to Obtain Kinetic Parameters of Chemical Exchange Processes

自旋饱和转移差异核磁共振（NMR SSTD）：一种新的工具来获得化学交换过程的动力学参数

This detailed protocol describes the new Spin Saturation Transfer Difference Nuclear Magnetic Resonance protocol (SSTD NMR), recently developed in our ...

Insights into the Interactions of Amino Acids and Peptides with Inorganic Materials Using Single-Molecule Force Spectroscopy

洞察氨基酸和多肽与无机材料的使用相互作用的单分子力谱

The interactions between proteins or peptides and inorganic materials lead to several interesting processes. For example, combining proteins with minerals ...

Coulomb Explosion Imaging as a Tool to Distinguish Between Stereoisomers

作为一种工具来区分立体异构体的库仑爆炸成像

This article shows how the COLTRIMS (Cold Target Recoil Ion Momentum Spectroscopy) or the "reaction microscope" technique can be used to distinguish ...

Electrochemical Impedance Spectroscopy as a Tool for Electrochemical Rate Constant Estimation

电化学阻抗谱作为电化学速率常数估计的一种工具

Electrochemical impedance spectroscopy (EIS) was used for advanced characterization of organic electroactive compounds along with cyclic voltammetry (CV). ...

Color Spot Test As a Presumptive Tool for the Rapid Detection of Synthetic Cathinones

色斑试验作为合成 Cathinones 快速检测的推定工具

Synthetic cathinones are a large class of new psychoactive substances (NPS) that are increasingly prevalent in drug seizures made by law enforcement and ...

A New Straightforward Method for Lipophilicity (logP) Measurement using 19F NMR Spectroscopy

A New Straightforward Method for Lipophilicity logP Measurement using 19F NMR Spectroscopy

一种利用19f 核磁共振光谱测定脂质性 (日志 p) 的新方法

Fluorination has become an effective tool to optimize physicochemical properties of bioactive compounds. One of the applications of fluorine introduction ...