Name: 作者聚焦：一种改进的顶空气相色谱-串联四极杆质谱法检测动物源性药物中三甲胺的技术
Uploaded: 2023-03-10T13:30:00
Description: Watch this Scientific Journal Video about An Improved Technique for Trimethylamine Detection in Animal-Derived Medicine by Headspace Gas Chromatography-Tandem Quadrupole Mass Spectrometry at JoVE.com

这项工作得到了国家自然科学基金（82173991）和四川省科学技术计划（2022YFS0442）的资助。

有关Pheretima，Periplaneta americana和Hirudo的药材的信息，请参见表1。成都中医药大学徐润春教授将他们鉴定为Pheretima aspergillum（E.Perrier），Periplaneta americana L.和Whitmania pigra Whitman的干燥尸体。
1. 标本提取
<ol><li>用草药研磨机（见材料表）粉碎Pheretima，Periplaneta americana和Hirudo，通过...

顶空 GC-MS 检测动物源性药物中的三甲胺

<ol>
	<li>Fan, H., 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=Material+basis+of+stench+of+animal+medicine:+a+review.">Material basis of stench of animal medicine: a review.</a> China Journal of Chinese Materia Medica. 47 (20), 5452-5459 (2022).</li><li>Deng, Y. J., 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+on+formation+and+taste-masking+technology+of+stench+of+animal+medicines.">Progress on formation and taste-masking technology of stench of animal medicines.</a> China Journal of Chinese Materia Medica. 45 (10), 2353-2359 (2020).</li><li>Casaburi, A., Piombino, P., Nychas, G. J., Villani, F., Ercolini, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bacterial+populations+and+the+volatilome+associated+to+meat+spoilage.">Bacterial populations and the volatilome associated to meat spoilage.</a> Food Microbiology. 45 (Pt A), 83-102 (2015).</li><li>Rouger, A., Tresse, O., Zagorec, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bacterial+contaminants+of+poultry+meat:+sources,+species,+and+dynamics.">Bacterial contaminants of poultry meat: sources, species, and dynamics.</a> Microorganisms. 5 (3), 50 (2017).</li><li>Bali&#241;o-Zuazo, L., Barranco, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+novel+liquid+chromatography-mass+spectrometric+method+for+the+simultaneous+determination+of+trimethylamine,+dimethylamine+and+methylamine+in+fishery+products.">A novel liquid chromatography-mass spectrometric method for the simultaneous determination of trimethylamine, dimethylamine and methylamine in fishery products.</a> Food Chemistry. 196, 1207-1214 (2016).</li><li>Zhao, C., 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=Ultra-efficient+trimethylamine+gas+sensor+based+on+Au+nanoparticles+sensitized+WO3+nanosheets+for+rapid+assessment+of+seafood+freshness.">Ultra-efficient trimethylamine gas sensor based on Au nanoparticles sensitized WO3 nanosheets for rapid assessment of seafood freshness.</a> Food Chemistry. 392, 133318 (2022).</li><li>Bota, G. M., Harrington, P. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Direct+detection+of+trimethylamine+in+meat+food+products+using+ion+mobility+spectrometry.">Direct detection of trimethylamine in meat food products using ion mobility spectrometry.</a> Talanta. 68 (3), 629-635 (2006).</li><li>Neyer, P., Bernasconi, L., Fuchs, J. A., Allenspach, M. D., Steuer, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Derivatization-free+determination+of+short-chain+volatile+amines+in+human+plasma+and+urine+by+headspace+gas+chromatography-mass+spectrometry.">Derivatization-free determination of short-chain volatile amines in human plasma and urine by headspace gas chromatography-mass spectrometry.</a> Journal of Clinical Laboratory Analysis. 34 (2), e23062 (2020).</li><li>Mitsubayashi, K., 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=Trimethylamine+biosensor+with+flavin-containing+monooxygenase+type+3+(FMO3)+for+fish-freshness+analysis.">Trimethylamine biosensor with flavin-containing monooxygenase type 3 (FMO3) for fish-freshness analysis.</a> Sensors &amp; Actuators B: Chemical. 103 (1-2), 463-467 (2004).</li><li>National Health and Family Planning Commission of the People's Republic of China. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> GB 5009. 179-2016. , 12 (2016).</li><li>Liu, X. 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W., Mao, B. P., Miao, S., Mao, X. H., Ji, S. <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+sulfur+dioxide+residues+in+sulfur+fumigated+Chinese+herbs+with+headspace+gas+chromatography.">Determination of sulfur dioxide residues in sulfur fumigated Chinese herbs with headspace gas chromatography.</a> Acta Pharmaceutica Sinica. 49 (2), 277-281 (2014).</li></ol>

动物源性药物来自动物的全身、器官或组织、生理或病理产物、排泄物或分泌物以及加工产品。TMA是动物源性药物中鱼腥味的重要来源;它是一种典型的恶臭物质，嗅觉阈值非常低（0.000032 × 10-6 V/V）和强烈的鱼腥味13。目前，常用的HS-GC-MS方法无法稳定、准确地检测动物源性药物中的TMA。
该方案在几个方面进行了改进：（1）TMA更具极性和碱性。该方?...

An erratum was issued for:&#160;<a href="https://www.jove.com/t/65291">An Improved Technique for Trimethylamine Detection in Animal-Derived Medicine by Headspace Gas Chromatography-Tandem Quadrupole Mass Spectrometry</a>. The Authors section was updated from:
Hui Ye1 
Xuemei Liu1 
Haozhou Huang2 
Lin Huang1 
Yang Bao1 
Hongyan Ma1 
Junzhi Lin3 
Xiaoming Bao4 
Dingkun Zhang1 
Runchun Xu1 
1State Key Laboratory of Southwestern Chinese Medicine Resources, Pharmacy School, Chengdu University of Traditional Chinese Medicine 
2Innovative Institute of Chinese Medicine and Pharmacy, Chengdu University of Traditional Chinese Medicine 
3TCM Regulating Metabolic Diseases Key Laboratory of Sichuan Province, Hospital of Chengdu University of Traditional Chinese Medicine 
4Shimadzu (China) Co., Ltd
to:
Hui Ye1 
Xuemei Liu1 
JiaBao Liao2 
Haozhou Huang3 
Lin Huang1 
Yang Bao1 
Hongyan Ma1 
Junzhi Lin4 
Xiaoming Bao5 
Dingkun Zhang1 
Runchun Xu1 
1State Key Laboratory of Southwestern Chinese Medicine Resources, Pharmacy School, Chengdu University of Traditional Chinese Medicine 
2China Resources Sanjiu Modern Chinese Medicine Pharmaceutical Co., Ltd 
3Innovative Institute of Chinese Medicine and Pharmacy, Chengdu University of Traditional Chinese Medicine 
4TCM Regulating Metabolic Diseases Key Laboratory of Sichuan Province, Hospital of Chengdu University of Traditional Chinese Medicine 
5Shimadzu (China) Co., Ltd

An erratum was issued for:&#160;<a href="https://www.jove.com/t/65291">An Improved Technique for Trimethylamine Detection in Animal-Derived Medicine by Headspace Gas Chromatography-Tandem Quadrupole Mass Spectrometry</a>. The Authors section was updated.

Erratum: An Improved Technique for Trimethylamine Detection in Animal-Derived Medicine by Headspace Gas Chromatography-Tandem Quadrupole Mass Spectrometry

利用动物器官和/或其副产品衍生的产品（此处称为动物源性药物）来治疗人类疾病正受到越来越多的关注。在治疗癌症、心血管疾病、肝硬化、乳腺炎等疾病中发挥重要作用，具有疗效强、用量小、临床疗效显著、特异性强等优点。但动物源性药物一般有明显的鱼腥味，影响患者依从性很大，对儿童尤其不利1,2。腥味主要来源于药物中所含的蛋白质、氨基酸、脂肪等物质，经脂肪酸氧化、氨基酸降解等方式分解，产生多种具有鱼腥味的物质2、3、4。其中，三甲胺（TMA）是一种具有鱼腥味的挥发性气体，广泛存在于腐烂或腐烂的动物源性食品中5。
到目前为止，气相色谱（GC）、液相色谱（LC）、离子色谱、分光光度法、液相色谱-质谱联用法（LC-MS）和传感器法已被普遍用于检测环境、食物和尿液中的TMA6,7,8,9。鉴于气相色谱柱和进样系统的低污染，以及高灵敏度、重现性和低检测限（0.1-1 mg/kg），顶空气相色谱-质谱（HS-GC-MS）法是食品和生物分析的首选方法8。目前，只有中国建立了食品中TMA的国家标准，HS-GC-MS是GB5009.179-2016标准10中的第一种方法。因此，选择上述HS-GC-MS方法检测动物源性药物中的TMA。在早期阶段，我们的研究小组发现食品中TMA的HS-GC-MS检测标准可以检测几种动物源性药物中的鱼腥味。结合研究结果11,12，可以证明TMA是动物源性药物中鱼腥味的常见关键物质。但发现实验结果重现性差，存在TMA逃逸、稳定性差等问题，无法通过该方法验证。这可能是由于碱液被注入顶空小瓶中，快速的酸碱反应导致小瓶中的压力增加，因此TMA从注射孔中逸出，从而阻止了TMA的稳定和准确检测。因此，本研究提出了一种改进的顶空气相色谱-串联四极杆质谱（HS-GC-MS/MS）检测方法来解决这一问题。
该方案通过在固体石蜡（一种良好的固液相变材料）的帮助下分离预处理中的酸碱反应物来改进样品预处理。随着石蜡随着恒温炉温度的升高而缓慢液化，TMA也在密封的顶空小瓶中缓慢释放，避免了剧烈而快速的酸碱反应引起的压力增加，保证了TMA检测的稳定准确。此外，GC-MS/MS中的顶空进样结合多种反应监测（MRM）模式有效地抑制了基质化学干扰，保证了结果的可靠性。方法验证结果表明，改进检测方法的线性、精密度和回收率均能满足要求，重现性好，灵敏度高。

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Centrifuge</td>
			<td>Beckman Coulter Trading (China) Co.</td>
			<td>SSC-2-0213</td>
			<td></td>
		</tr>
		<tr>
			<td>Chinese herbal medicine grinder</td>
			<td>Zhejiang Yongkang Xi&#39;an Hardware and Pharmaceutical Factory</td>
			<td>HX-200K</td>
			<td></td>
		</tr>
		<tr>
			<td>Convection oven</td>
			<td>Sanyo Electric Co., Ltd</td>
			<td>MOV-112F</td>
			<td></td>
		</tr>
		<tr>
			<td>Decapper for 20 mm Aluminum caps</td>
			<td>ANPEL Laboratory Technologies (Shanghai) Inc</td>
			<td>V1750004</td>
			<td></td>
		</tr>
		<tr>
			<td>Electronic balance</td>
			<td>Shimadzu Corporation Japan</td>
			<td>AUW220D</td>
			<td></td>
		</tr>
		<tr>
			<td>Gas chromatography mass spectrometry</td>
			<td>Shimadzu Corporation Japan</td>
			<td>TQ-8050 NX</td>
			<td></td>
		</tr>
		<tr>
			<td>Headspace Vial</td>
			<td>ANPEL Laboratory Technologies (Shanghai) Inc</td>
			<td>25760200</td>
			<td></td>
		</tr>
		<tr>
			<td>Homogenizer</td>
			<td>Shanghai biaomo Factory</td>
			<td>FJ200-SH</td>
			<td></td>
		</tr>
		<tr>
			<td>Preassembled Cap</td>
			<td>ANPEL Laboratory Technologies (Shanghai) Inc</td>
			<td>L4150050</td>
			<td></td>
		</tr>
		<tr>
			<td>Sample sieve</td>
			<td>Zhenxing Sieve Factory</td>
			<td>/</td>
			<td></td>
		</tr>
		<tr>
			<td>SH-Volatile Amine</td>
			<td>Chengdu Meimelte Technology Co., Ltd</td>
			<td>227-3626-01</td>
			<td></td>
		</tr>
		<tr>
			<td>Sodium hydroxide</td>
			<td>Chengdu Chron Chemicals Co., Ltd</td>
			<td>2022101401</td>
			<td></td>
		</tr>
		<tr>
			<td>Solid paraffin wax</td>
			<td>Shanghai Hualing Kangfu apparatus factory</td>
			<td>20221112</td>
			<td></td>
		</tr>
		<tr>
			<td>Trichloroacetic acid</td>
			<td>Chengdu Chron Chemicals Co., Ltd</td>
			<td>2022102001</td>
			<td></td>
		</tr>
		<tr>
			<td>Trimethylamine hydrochloride</td>
			<td>Chengdu Aifa Biotechnology Co., Ltd</td>
			<td>AF22022108</td>
			<td></td>
		</tr>
		<tr>
			<td>Ultra-pure water system</td>
			<td>Sichuan Youpu Ultrapure Technology Co., Ltd</td>
			<td>UPR-11-5T</td>
			<td></td>
		</tr>
	</tbody>
</table>

an improved technique for trimethylamine detection in animal-derived medicine by headspace gas chromatography-tandem quadrupole mass spectrometry

动物源性药物具有鲜明的特点和显著的疗效，但大多有明显的鱼腥味，导致临床患者的依从性较差。三甲胺（TMA）是动物源性药物中关键的鱼腥味成分之一。由于加入碱液后快速的酸碱反应导致顶空小瓶压力增加，导致TMA从顶空小瓶中逸出，阻碍了动物源性药物鱼腥味的研究进展，因此使用现有的检测方法很难准确识别TMA。在这项研究中，我们提出了一种受控检测方法，该方法引入了石蜡层作为酸和碱液之间的隔离层。通过恒温炉加热使石蜡层缓慢液化，可以有效控制TMA的产量。该方法表现出令人满意的线性、精密的实验和回收率，重现性好，灵敏度高。为动物源性药物除臭提供技术支持。

Treating human diseases by utilizing products derived from animal parts and/or their by-products (referred to here as animal-derived medicines) is receiving increased attention. They play an important role in treating cancer, cardiovascular disease, liver cirrhosis, mastitis, and other diseases, with the advantages of a strong effect, small dosage, and significant and specific clinical efficacy. However, animal-derived medicines generally have a prominent fishy odor, which greatly affects patients&#39; compliance, and are especially unfavorable for children1,2. The fishy odor mainly comes from the proteins, amino acids, fats, and other substances contained in the medicine, which are decomposed through fatty acid oxidation, amino acid degradation, and other ways to produce a variety of substances with a fishy odor2,3,4. Among them, trimethylamine (TMA) is a volatile gas with a fishy odor that widely exists in rotting or rotten animal-derived foods5.
Until now, gas chromatography (GC), liquid chromatography (LC), ion chromatography, spectrophotometry, liquid chromatography-mass spectrometry (LC-MS), and sensor methods have commonly been used to detect TMA in the environment, food, and urine6,7,8,9. In view of the low contamination of the GC column and injection system, as well as the high sensitivity, reproducibility, and low detection limit (0.1-1 mg/kg), the headspace gas chromatography-mass spectrometry (HS-GC-MS) method was preferred for food and biological analysis8. At present, only China has established a national standard for TMA in food, and HS-GC-MS is the first method in the GB5009.179-2016 standard10. Therefore, the above HS-GC-MS method was selected to detect TMA in animal-derived medicine. In the early stage, our research group found that the HS-GC-MS detection standard for TMA in food could detect the fishy odor in several animal-derived medicines. Combined with the results of the studies11,12, it could be proved that TMA is the common key substance of fishy odor in animal-derived medicines. However, it was found that the reproducibility of the experimental results was poor, and there were problems such as TMA escape and poor stability, which could not be verified by the methodology. This could be due to the fact that the lye was injected into the headspace vial and the rapid acid-base reaction led to increased pressure in the vial, thus TMA escaped from the injection pore, preventing the stable and accurate detection of TMA. Therefore, this study proposed an improved headspace gas chromatography-tandem quadrupole mass spectrometry (HS-GC-MS/MS) detection method to address these problems.
The protocol improves the sample pretreatment by separating the acid-base reactants in the pretreatment with the help of solid paraffin, a good solid-liquid phase change material. As the paraffin slowly liquefied with the temperature rise of the thermostatic furnace, TMA was also slowly released in the sealed headspace vial, avoiding the pressure increase caused by the violent and rapid acid-base reaction and ensuring stable and accurate TMA detection. Further, the headspace injection combined with multiple reaction monitoring (MRM) modes) in GC-MS/MS effectively suppressed matrix chemical interference and ensured the reliability of the results. The results of the methodological validation proved that the linearity, precision test, and recovery rate of the improved detection method could meet the requirements, with good reproducibility and high sensitivity.

作者聚焦：一种改进的顶空气相色谱-串联四极杆质谱法检测动物源性药物中三甲胺的技术  

一种改进的顶空气相色谱-串联四极杆质谱法检测动物源性药物中三甲胺的技术

The scope of our research is a material basis in the variation of fish odor in animal medicine. This protocol provides a simple pretreatment method and accurate detection of trimethylamine in animal medicines. The simple pretreatment methods and the programmed parameters of HS-GC mass/mass of this protocol, need to be further optimized, and we still have a lot of work to do.Our protocol adopts the multi-direction monitoring mode of GC mass/mass, combined with a unique, simple pretreatment, which is not only the first pretreatment for trimethylamine analysis, but also the first analytical mode to be used.

该协议的预处理原理和操作原理图分别如图 1 和 图2所示。TMA的峰时间为2.3 min，峰形尖锐，不受其他杂质干扰（图3）。测定0.1-10 μg/mL TMA标准溶液的线性范围，以TMA浓度为横坐标，峰面积为纵坐标，绘制标准曲线。线性回归方程为y = 2522482x + 24255，相关系数（R2）= 0.9998，表现出良好的线性关系。LOD和LOQ的计算分别?...

Watch this Scientific Journal Video about An Improved Technique for Trimethylamine Detection in Animal-Derived Medicine by Headspace Gas Chromatography-Tandem Quadrupole Mass Spectrometry at JoVE.com

本文描述了一种适用于测定动物源性药物中三甲胺（TMA）的顶空气相色谱-串联四极杆质谱（HS-GC-MS/MS）方法。该方案包括样品预处理、顶空处理、分析条件、方法验证以及动物源性药物中TMA的测定。

Animal-derived medicines have distinctive characteristics and significant curative effects, but most of them have an obvious fishy odor, resulting in the ...

我们的研究范围是动物医学中鱼味变化的物质基础。该方案提供了一种简单的预处理方法和动物药物中三甲胺的准确检测。该协议的简单预处理方法和HS-GC质量/质量数的编程参数需要进一步优化，我们还有很多工作要做。我们的方案采用气相色谱质量/质量数的多方向监测模式，结合独特、简单的预处理，不仅是三甲胺分析的第一个预处理，也是第一个要使用的分析模式。

an-improved-technique-for-trimethylamine-detection-animal-derived

Research

JoVE Journal

Chemistry

An Improved Technique for Trimethylamine Detection in Animal-Derived Medicine by Headspace Gas Chromatography-Tandem Quadrupole Mass Spectrometry

Animal-derived medicines have distinctive characteristics and significant curative effects, but most of them have an obvious fishy odor, resulting in the poor compliance of clinical patients. Trimethylamine (TMA) is one of the key fishy odor components in animal-derived medicine. It is difficult to identify TMA accurately using the existing detection method due to the increased pressure in the headspace vial caused by the rapid acid-base reaction after the addition of lye, which causes TMA to escape from the headspace vial, stalling the research progress of the fishy odor of animal-derived medicine. In this study, we proposed a controlled detection method that introduced a paraffin layer as an isolation layer between acid and lye. The rate of TMA production could be effectively controlled by slowly liquefying the paraffin layer through thermostatic furnace heating. This method showed satisfactory linearity, precision experiments, and recoveries with good reproducibility and high sensitivity. It provided technical support for the deodorization of animal-derived medicine.

Here, a headspace gas chromatography-tandem quadrupole mass spectrometry (HS-GC-MS/MS) method suitable for the determination of trimethylamine (TMA) in animal-derived medicines is described. The protocol includes sample pretreatment, headspace treatment, analysis conditions, methodological validation, and the determination of TMA in animal-derived medicines.

科研

化学

Trimethylamine Detection in Animal-Derived Medicine by Headspace GC-MS

To begin, crush the medicinal materials Pheretima, Periplaneta americana, and Hirudo with an herbal grinder. Sift the medicinal powder through standard drug sieves of number two and number four. Collect the powder between the two sieves to obtain the required sample powder.Take one gram of the powder in a 50 milliliter plastic centrifuge tube. Add 20 milliliters of 5%trichloroacetic acid solution and homogenize at 1, 000 RPM for one minute with a high speed dispersion homogenizer. After homogenization, centrifuge the homogenate at 1, 717 G for five minutes at room temperature and filter the supernatant through an absorbent cotton-dipped glass funnel into a 50 milliliter volumetric flask.After repeating the extraction process twice with 15 and 10 milliliters of 5%trichloroacetic acid solution, combine the filtrates and make up the volume to 50 milliliters with 5%trichloroacetic acid solution. Next, accurately add two milliliters of sodium hydroxide solution and 0.5 grams of solid paraffin in 20 milliliter headspace vials. Then place them in an oven at 70 degrees Celsius for about 30 minutes.Take the vials out and let them cool down to room temperature so that the paraffin solidifies. To process the sample headspace, add two milliliters of each sample extraction solution to the solidified paraffin containing vials. Press the cap and seal the vial.Put the sealed headspace vials on the GCMS for measurement. To obtain the standard curve, aspirate a series of two milliliters of trimethylamine standard solution on top of the solidified paraffin layer. Put the sealed headspace vials on the machine for trimethylamine measurement.To perform the precision test, aspirate two milliliters of 0.1 micrograms per milliliter trimethylamine standard solution on top of the solidified paraffin layer. Carry out six parallel tests in the machine following the manufacturer's instructions. For the recovery rate experiment, bake several batches of the sample powder in an oven until no triethylamine is detected in GCMS as demonstrated previously.Next, take each one gram of oven baked and fineable powder into separate 50 milliliter plastic centrifuge tubes. Add 50 microliters of trimethylamine standard solution to all the tubes and extract with 5%trichloroacetic acid solution as demonstrated previously. The retention time of trimethylamine was found to be 2.3 minutes with a sharp peak and no interference from other impurities.Pheretima, Periplaneta americana, and Hirudo samples subjected to spiked recovery tests by drying to reduce triethylamine in the herbs showed average recovery rates of 84.49, 94.66, and 85.67%respectively. Triethylamine was detected in nine batches of herbs with concentrations ranging from 13.23 to 271.63 milligrams per kilogram.