Name: chemical analysis of water-accommodated fractions of crude oil spills using tims-ft-icr ms
Uploaded: 2017-03-03T14:00:00
Description: Watch this Scientific Journal Video about Chemical Analysis of Water-accommodated Fractions of Crude Oil Spills Using TIMS-FT-ICR MS at JoVE.com

这项工作是由美国国立卫生研究院（批准号：R00GM106414到FFL）的支持。我们要感谢佛罗里达国际大学的高级质谱设备的支持。

1.低能量水容纳馏分的准备（LEWAF） <ol><li>通过漂洗用二氯甲烷瓶子以除去任何潜在的污染物干净的2升抽吸瓶。 </li><li>灌装瓶用50ml二氯甲烷，将其关闭，并搅拌30秒。沥干他们到合适的废物容器。重复总共洗涤三次。 </li><li>使用一个抽吸瓶照射曝光而另一个瓶作为对照样品（使用重复组，每组如果可能的）。 </li><li>每用于33份每千最后盐度1升的水混合35克海盐混合物准备人工海水。过滤下小的...

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M., 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=Expansion+of+the+analytical+window+for+oil+spill+characterization+by+ultrahigh+resolution+mass+spectrometry:+beyond+gas+chromatography.">Expansion of the analytical window for oil spill characterization by ultrahigh resolution mass spectrometry: beyond gas chromatography.</a> Environ Sci Technol. 47 (13), 7530-7539 (2013).</li><li>Fernandez-Lima, F. A., 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=Petroleum+crude+oil+characterization+by+IMS-MS+and+FTICR+MS.">Petroleum crude oil characterization by IMS-MS and FTICR MS.</a> Anal Chem. 81 (24), 9941-9947 (2009).</li><li>Benigni, P., Marin, R., Fernandez-Lima, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Towards+unsupervised+polyaromatic+hydrocarbons+structural+assignment+from+SA-TIMS-FTMS+data.">Towards unsupervised polyaromatic hydrocarbons structural assignment from SA-TIMS-FTMS data.</a> Int J Ion Mobil Spectrom. 18 (3), 151-157 (2015).</li><li>Benigni, P., Thompson, C. J., Ridgeway, M. E., Park, M. A., Fernandez-Lima, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Targeted+high-resolution+ion+mobility+separation+coupled+to+ultrahigh-resolution+mass+spectrometry+of+endocrine+disruptors+in+complex+mixtures.">Targeted high-resolution ion mobility separation coupled to ultrahigh-resolution mass spectrometry of endocrine disruptors in complex mixtures.</a> Anal Chem. 87 (8), 4321-4325 (2015).</li><li>Benigni, P., Fernandez-Lima, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Oversampling+Selective+Accumulation+Trapped+Ion+Mobility+Spectrometry+coupled+to+FT-ICR+MS:+Fundamentals+and+Applications.">Oversampling Selective Accumulation Trapped Ion Mobility Spectrometry coupled to FT-ICR MS: Fundamentals and Applications.</a> Analytical Chemistry. , (2016).</li><li>Castellanos, A., 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=Fast+Screening+of+Polycyclic+Aromatic+Hydrocarbons+using+Trapped+Ion+Mobility+Spectrometry+Mass+Spectrometry.">Fast Screening of Polycyclic Aromatic Hydrocarbons using Trapped Ion Mobility Spectrometry Mass Spectrometry.</a> Anal Methods. 6 (23), 9328-9332 (2014).</li><li>Benigni, P., DeBord, J. D., Thompson, C. J., Gardinali, P., Fernandez-Lima, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Increasing+Polyaromatic+Hydrocarbon+(PAH)+Molecular+Coverage+during+Fossil+Oil+Analysis+by+Combining+Gas+Chromatography+and+Atmospheric-Pressure+Laser+Ionization+Fourier+Transform+Ion+Cyclotron+Resonance+Mass+Spectrometry+(FT-ICR+MS).">Increasing Polyaromatic Hydrocarbon (PAH) Molecular Coverage during Fossil Oil Analysis by Combining Gas Chromatography and Atmospheric-Pressure Laser Ionization Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR MS).</a> Energy &amp; Fuels. 30 (1), 196-203 (2016).</li><li>Qi, Y., 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=Absorption-Mode+Fourier+Transform+Mass+Spectrometry:+the+Effects+of+Apodization+and+Phasing+on+Modified+Protein+Spectra.">Absorption-Mode Fourier Transform Mass Spectrometry: the Effects of Apodization and Phasing on Modified Protein Spectra.</a> Journal of the American Society for Mass Spectrometry. 24 (6), 828-834 (2013).</li><li>Lababidi, S., Schrader, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Online+normal-phase+high-performance+liquid+chromatography/Fourier+transform+ion+cyclotron+resonance+mass+spectrometry:+Effects+of+different+ionization+methods+on+the+characterization+of+highly+complex+crude+oil+mixtures.">Online normal-phase high-performance liquid chromatography/Fourier transform ion cyclotron resonance mass spectrometry: Effects of different ionization methods on the characterization of highly complex crude oil mixtures.</a> Rapid Communications in Mass Spectrometry. 28 (12), 1345-1352 (2014).</li></ol>

该议定书中的关键步骤 LEWAFs的化学复杂性需要，以便使实验室实验来准确反映自然发生准确制剂。数据的有效评估取决于三个标准：尽量减少引进的文物在整个样品处理（ 例如，准备LEWAF，取样，提取，并准备样品进行分析的），验证实验方案（ 即使用暗控制对于光照射试验），并验证该仪器的性能（ 即，验证MS和IMS性能通过使用标准）。 <p class="jove_co...

有环境暴露原油的来源众多，无论是从自然原因和人为风险。在释放到环境中，特别是在海洋中，原油可经历分区，与浮油的表面上的形成，挥发性组分到大气中的损失，和沉积。然而，难溶油和确实发生的水，并将该混合物，这是不经典溶解，低能量混合形成什么作为低能量的水容纳部分（LEWAF）简称。在水中的油组分的增溶的油 - 水界面的暴露于太阳辐射中，通常提高。在海洋中的原油的照片增溶可以因此暴露于太阳辐射和/或由于酶促降解1,2经历显著化学变化。理解这些化学变化和<html>他们是如何发生在散装矩阵（ 即，原油）的存在是为了减轻这种曝光，对环境的影响的基础。 以前的研究已经表明，原油经受氧化，特别是多环芳香烃（PAHs），这代表污染一个危害生物，经过生物积累的剧毒源，并且是生物活性3，5，6。因为它们只发生在本体基体的存在理解不同的氧合过程的产物是具有挑战性的。因此，一个单一的标准分析可能不具有代表性的天然存在的变化。该LEWAF的编制必须复制了发生在一个环境背景自然过程。特别感兴趣的是多环芳烃的充氧，发生由于太阳辐射。 T“&gt;在水容纳部分的研究的第二个挑战是在样品中的不同的化学成分的分子鉴定。由于样品的复杂性，所造成的高的质量和氧气的程度，氧化产物是通常不适合于传统的分析用气相色谱法与质谱分析7,8结合进行。另一种方法是通过利用超高质量分辨率质谱技术（ 例如，FT-ICR质谱来表征样品的化学式中的变化），通过耦合TIMS到FT-ICR质谱，除了在MS域中的同量异序的分离，离子迁移光谱（IMS）的尺寸为存在于样品9，10，11中的不同的异构体的分离和特征信息。与大气压力激光组合电离（APLI）源，分析可以是选择性的样品中发现的共轭分子，允许改变该多环芳烃经受是准确特征12,13。 在这项工作中，我们描述了为了研究油成分的变换处理暴露于光照射LEWAFs的制备的协议。我们还说明了在光照射时发生的变化，以及对样品提取的过程。我们也将呈现使用APLI与耦合用FT-ICR质谱表征在LEWAF多环芳烃作为曝光于光的功能TIMS。

<table border="0" cellpadding="0" cellspacing="0" width="915">
	<tbody>
		<tr height="20">
			<td height="20" style="height:20px;width:228px;">Reagents</td>
			<td style="width:156px;"></td>
			<td style="width:156px;"></td>
			<td style="width:375px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">methylene chloride</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">methanol</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">toluene</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Na2SO4</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Crude oil</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Instant Ocean&#174;</td>
			<td>Aquarium Systems</td>
			<td></td>
			<td>33 ppt salinity with 0.45 &#956;m pore filtration&#160;</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Name&#160;</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Equipment</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Suntext XLS+</td>
			<td>Atlas Chicalo Ill, USA</td>
			<td></td>
			<td>1500 w xeon arc lamp, light intensity of 765 W/m2&#160;</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Atmospheric Pressure Laser Ionization</td>
			<td>Bruker Daltonics Inc, MA</td>
			<td></td>
			<td>Note a 266 nm laser is used</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">TIMS-FT-ICR MS Instrument</td>
			<td>Bruker Daltonics Inc, MA</td>
			<td></td>
			<td>The set up we had consisted of a 7T magnet with an infinity cell</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Name&#160;</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Software</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">DataAnalysis 4.2</td>
			<td>Bruker Daltonics Inc, MA</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Python 2.7</td>
			<td></td>
			<td></td>
			<td>Requires Numpy, Scipy, Pandas, glob, oct2py, and os</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Octave 4.0</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
	</tbody>
</table>

chemical analysis of water-accommodated fractions of crude oil spills using tims-ft-icr ms

多种化学过程控制石油原油是如何被纳入到海水中，也发生加班的化学反应。研究这种系统需要的样本，以准确的复制出现在自然界的水容纳部分的自然形成的精心准备。低能量水容纳部分（LEWAF）都是严格在设定的比例混合原油和水配制。然后抽吸瓶照射，并在设定的时间点，水进行采样，并使用标准技术提取。第二个挑战是样本，必须考虑到，随时间发生的化学变化的代表特性。可以使用耦合到定制的俘获离子迁移谱傅立叶变换离子回旋共振质谱（TIMS-FT常压激光电离源来执行LEWAF的芳烃馏分的目标分析-ICR MS）。所述TIMS-FT-ICR质谱分析提供的高分辨率离子迁移和超高分辨率MS分析，其中，还允许同分异构组分的鉴定可以通过碰撞截面（CCS）和化学式。结果表明，随着油 - 水混合物被暴露于光，有表面油的显著光溶解到水中。随着时间的推移，溶解的分子的化学转变发生时，在含氮和含硫物种的标识的数量有利于那些具有更大的氧含量比在基础油中典型地观察到的降低。

通过TIMS-FT-ICR MS结果中基于M / Z和TIMS捕获电压的二维频谱LEWAF分析。各样品，在不同时间点拍摄，因此，可以根据特征的改变的化学成分，由化学式的分布和由IMS（ 见图1）所确定的异构体的贡献所观察到的。通常情况下，M / Z信息可以用来为元素式分配给分析峰。使用APLI的允许与芳香双键分子与更高的灵敏度15分析，电离广泛的...

Watch this Scientific Journal Video about Chemical Analysis of Water-accommodated Fractions of Crude Oil Spills Using TIMS-FT-ICR MS at JoVE.com

Chemical Analysis of Water-accommodated Fractions of Crude Oil Spills Using TIMS-FT-ICR MS

原油的低能量水容纳部分（LEWAF）是一个具有挑战性的系统来分析，因为随着时间的推移，这种复杂的混合物发生化学转变。这个协议说明了LEWAF样品的准备和用于通过俘获离子迁移谱-FT-ICR质谱进行光照射和化学分析方法。

原油水容纳组分的化学分析泄漏使用TIMS-FT-ICR MS

Multiple chemical processes control how crude oil is incorporated into seawater and also the chemical reactions that occur overtime. Studying this system ...

The overall goal of these experiments is to illustrate the analytical advantages of enabling emerging technologies based on TIMS-FT-ICR MS for the molecular characterization of complex mixtures, such as water-accommodated fractions for crude oils. The TIMS-FT-ICR MS coupling combines two of the most comprehensive orthogonal and alluvial techniques for the analysis of complex mixtures. TIMS-FT-ICR MS coupling permits in a single analysis the characterization of thousands of molecular components with mobility resolving powers of over 150, mass resolution of 500, 000, and sub-ppm mass accuracy.TIMS-FT-ICR MS enables the separation, identification, and quantitation at the molecular level of complex mixtures, based on differences in size, charge and mass with minimal sample appropriation. To begin the LEGAF preparation, add 50 milliliters of dicholomethane to a two liter glass aspirator bottle. Close the bottle and agitate the bottle for 30 seconds.Discard the dichloromethane wash, and repeat this process two more times. Wash one more two liter aspirator bottle in this way, then add about 1.6 liters of filtered artificial seawater with a salinity of 33 parts per thousand to each bottle. Add a stir bar, and then use a gas-tight syringe to add sufficient crude oil sample to each bottle to achieve a final concentration of one gram per liter of oil and seawater.Wrap the bottles in aluminum foil to exclude light, and stir the mixtures at approximately 100 RPM for 24 hours to finish preparing the LEWAF. It's important that care is used when first mixing the oil and water to avoid over-mixing the solution. Next, unwrap one of the LEWAF bottles in aluminum foil, leaving one as the dark control.Place the bottles in the solar irradiator with the temperature set to maintain the samples at 25 degrees Celsius. Irradiate the mixtures continuously for the desired experiment length. At set intervals during the experiment, obtain 150 milliliter fractions from each bottle by uncorking the bottle and opening the drain valve.Extract each sample aliquot using 50 milliliters of dichloromethane three times using a separatory funnel. Shake the funnel for two minutes each time, remembering to regularly vent the funnel to avoid pressure buildup. Drain the sample into a flat-bottom flask through a funnel containing sulfate and rinse the sodium sulfate with additional DCM.Concentrate the extract to 15 milliliters using a hot water bath set at 58 degrees Celsius. Transfer the concentrate into a concentration tube, rinsing the flask with DCM. Concentrate each sample to one milliliter under a gentle stream of nitrogen gas.For each concentrated sample, using a glass positive displacement micropipette, add 990 microliters of a one to one by volume mixture of methanol and toluene to a glass vial. Then mix in 10 microliters of the sample. To begin the FTR-ICR MS analysis, set the instrument to Operate mode.Draw a sample into a sample syringe. Set the infusion rate to 200 microliters per hour, the nebulizer pressure to two bar, and the vaporizer temperature to 300 degrees Celsius. Set the dry gas rate to 1.2 liters per minute and the temperature to 220 degrees Celsius.Then set the instrument to Tune mode. Based on the resulting spectrum adjust the instrument parameters and recalibrate the mass spectrometer to improve the ion transmission and detection for the desired range of mass to charge ratios. Once the instrument parameters have been optimized, exit Tune mode.Set the desired number of scans to be average per mass spectrum, and then acquire the spectrum. To begin the trapped ion mobility spectrometry analysis turn on the external breaker to the TIMS instrument to engage TIMS mode. Set the FT-ICR instrument to chromatography mode.Turn on the supplementary roughing pump and set the inlet and outlet pressures to the desired values using the TIMS control valve. Allow the pump to warm up for at least three hours, then perform a fast sweep over a wide voltage range at a low IMS and MS resolution to identify the needed voltage range for the analysis. Once the range has been identified, set the voltage per frame to 0.1 volts.Set the number of frames to cover the entirety of the DeltaV ramp and run the analysis. After performing the analyses, process the data with the appropriate software and scripts to determine the chemical composition and mobility values of identified peaks. After sunlight irradiation of an LEWAF of a crude oil sample, changes in the chemical complexity are observed as a function of exposure time.This complexity was detected and visualized in a 2D spectrum based on mass to charge ratio and ion mobility. The use of APLI resulted in greater analytical sensitivity to molecules with double bonds. Four molecular classes were identified in the sample.Distribution plots of double bond equivalents as a function of the number of carbons were used to monitor changes in the molecular composition over time. Two-dimensional plots of inverse mobility versus carbon number were created, with the double bond equivalents represented as the color of each point. Linear trends were observed for each of the four common molecular classes.After watching this video you should have a good understanding of the basic steps and unique advantages of APLI-TIMS-FT-ICR MS for the analysis of LEWAF samples as well as other complex mixtures. While attempting this procedure it's important to remember that sample integrity, such as reducing sources of contamination, is fundamental for accurate results. The characterization at the molecular level of the water-accommodated fractions of crude oils, the transformation products, and their fate during exposure to sunlight in the ocean is of the utmost environmental importance.Compared to other separation techniques such as liquid chromatography and gas chromatography, TIMS separation occurs in a shorter time scale, and is timing dependent, which permits better coupling with ultra high resolution MS analyzers while providing collision cross sections and chemical formulas in a single analysis. The generation of new comprehensive analytical tools for the analysis of complex mixtures at molecular level, such as TIMS-FT-ICR MS has great implications for our understanding of the chemical transformations and fate of crude oil in the ocean.

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环境科学

LC-MS Analysis of Human Platelets as a Platform for Studying Mitochondrial Metabolism

人类血小板的LC-MS分析作为研究线粒体代谢的平台

Perturbed mitochondrial metabolism has received renewed interest as playing a causative role in a range of diseases. Probing alterations to metabolic ...

Methods of Soil Resampling to Monitor Changes in the Chemical Concentrations of Forest Soils

土壤重采样的方法监控森林土壤的化学浓度的变化

Recent soils research has shown that important chemical soil characteristics can change in less than a decade, often the result of broad environmental ...

Measurement of the Rheology of Crude Oil in Equilibrium with CO2 at Reservoir Conditions

Measurement of the Rheology of Crude Oil in Equilibrium with CO2 at Reservoir Conditions

与CO平衡的原油流变学测量<sub&gt; 2</sub&gt;在水库条件

A rheometer system to measure the rheology of crude oil in equilibrium with carbon dioxide (CO2) at high temperatures and pressures is described. The ...

Dispersion of Nanomaterials in Aqueous Media: Towards Protocol Optimization

纳米材料在水介质中的分散: 对协议优化的研究

The sonication process is commonly used for de-agglomerating and dispersing nanomaterials in aqueous based media, necessary to improve homogeneity and ...

Microfluidic Devices for Characterizing Pore-scale Event Processes in Porous Media for Oil Recovery Applications

微流体器件用于表征多孔介质中的孔隙尺度事件过程, 用于采油应用

Microfluidic devices are versatile tools for studying transport processes at a microscopic scale. A demand exists for microfluidic devices that are ...

The Effect of the Application of Thyme Essential Oil on Microbial Load During Meat Drying

百里香精油应用于肉类干燥过程中微生物负荷的影响

Meat is a high protein meal that is used in the preparation of jerky, a popular food snack, where preservation and safety are important. To assure food ...

Identification of Pharmaceuticals in The Aquatic Environment Using HPLC-ESI-Q-TOF-MS and Elimination of Erythromycin Through Photo-Induced Degradation

高效液相色谱-ESI-Q-MS 与红霉素通过光致降解法鉴定水生环境中的药物

Monitoring pharmaceuticals throughout the water cycle is becoming increasingly important for the aquatic environment and eventually for human health. ...

A Novel Method for the Pentosan Analysis Present in Jute Biomass and Its Conversion into Sugar Monomers Using Acidic Ionic Liquid

利用酸性离子液体戊聚糖分析黄麻生物量及其转化为糖单体的新方法

Recently, ionic liquids (ILs) are used for biomass valorization into valuable chemicals because of their remarkable properties such as thermal stability, ...

Isolation of Mandibular Gland Reservoir Contents from Bornean 'Exploding Ants' (Formicidae) for Volatilome Analysis by GC-MS and MetaboliteDetector

Isolation of Mandibular Gland Reservoir Contents from Bornean 'Exploding Ants' Formicidae for Volatilome Analysis by GC-MS and MetaboliteDetector

婆罗洲 "爆炸蚂蚁" (蚁科昆虫) 对下颌腺储层含量的分离--gc-ms 和 MetaboliteDetector Volatilome 分析

The aim of this manuscript is to present a protocol describing the metabolomic analysis of Bornean &#39;exploding ants&#39; belonging to the Colobopsis ...