calibration and data acquisition on high-resolution tandem mass spectrometer for chemical composition analysis

<meta charset="utf8"></head><body>通过 UPLC-TOF 质谱法鉴定 双色 Gynura bicolor 的化学成分

Traditional Chinese medicine (TCM) has been clinically practiced in China for thousands of years, and it plays a vital role in maintaining the health of Chinese people1. The composition of TCM is diverse and complex, and TCM has been widely reported in many qualitative studies focusing on the chemical composition2. The chemical components in TCM can be roughly divided into the following categories such as alkaloids, organic acids, phenylpropanoids, coumarins, lignans, quinones, flavonoids, terpenoids, triterpenoid saponins, steroid saponins, cardiac glycosides, and tannins3. Given the large numbers of unknown components and indistinguishable isomers in TCM, the separation and analysis of the desired chemical components are important subjects for the fundamental research of TCM4.
Ultra-high-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) has been applied to analyze substances in traditional Chinese medicine (TCM), which can be separated by ultra-high-performance liquid chromatography5,6. The high resolution of MS can provide extensive ion information, which is used for database analysis with error less than 5 ppm7. After turning on the collision energy, the secondary MS mode can obtain secondary fragment ions, whose intensity and number are affected by the magnitude of energy8. 
Gynura bicolor DC. (BFH), a perennial stemless herb widely used for medicine and food (Figure 1A), is a rare and endangered plant unique to China9. BFH has abundant anthocyanins, polyphenols, flavonoids, and strong antioxidant capacity10. BFH has medicinal effects including clearing heat, cooling blood, moistening the lung, relieving cough, dispersing stasis, relieving swelling, relieving summer heat, and eliminating heat. Few studies have focused on the chemical composition of BFH11. Polyphenols and flavonoids contain numerous isomers, which make the identification of the complex compounds in BFH difficult. A universal method for the identification of chemical components must be developed, which can be applied to all kinds of TCM. This study aimed to report a systematic protocol for studying chemical constituents of BFH based on solvent extraction and integrated data via UPLC-Q-TOF-MS.

<meta charset="utf8"></head><body>用于高分辨率串联质谱分析的 Gynura bicolor DC 样品的制备

用于研究双色 DC 化学成分的高分辨率串联质谱法

Begin by sample pretreatment. Wash the whole herb of BFH in pure water until there are no visible deposits and impurities. Place the clean BFH in a dish and then place it in the oven at 50 degrees Celsius for 24 hours.Crush the dried BFH in a high-speed multifunctional crusher. Transfer the coarse powder into a 50-mesh sieve. Collect the fine powder in an airtight bag and store it in a drying tower.Then accurately weigh six BFH samples of 0.25 grams each and place them in six conical flasks. Add 30 milliliters of organic solvent to each conical flask. Transfer the mixture to an ultrasound bath sonicator for 30 minutes at 25 degrees Celsius.Next, centrifuge the sample at 14, 000g for five minutes. Using an injection syringe and the 0.22-micrometer organic microporous membrane filter, filter all the supernatants into two-milliliter sample bottles.

在高分辨率串联质谱仪上进行化学成分分析的校准和数据采集

calibration-data-acquisition-on-high-resolution-tandem-mass

Research

JoVE Journal

Chemistry

Calibration and Data Acquisition on High-Resolution Tandem Mass Spectrometer for Chemical Composition Analysis

33 次观看. 首先，制备 0.5 毫摩尔甲酸钠溶液。启动 UPLCQOFMS 控制软件后，打开样品流速控制面板中的 MS 调谐窗口，在进样流速选项中设置 25 μL/min，在储液槽选项中选择 C，然后等待大约一分钟以结束自动吹扫。下一步，点击流开始输送甲酸钠溶液。单击正按钮切换到正离子模式，单击灵敏度按钮切换到灵敏度模式。然后打开 MS 控制台窗口，依次选择 syna...

视频: 在高分辨率串联质谱仪上进行化学成分分析的校准和数据采集

High-resolution Tandem Mass Spectrometry for Studying Chemical Constituents of Gynura bicolor DC

The separation and analysis of the desired chemical components are important subjects for the fundamental research of traditional Chinese medicine (TCM). Ultra-high-performance liquid chromatography quadrupole time-of-flight tandem mass spectrometry (UPLC-Q-TOF-MS/MS) has gradually become a leading technology for the identification of TCM ingredients. Gynura bicolor DC. (BFH), a perennial stemless herb used for medicine and food in China has medicinal effects such as clearing heat, moistening the lung, relieving cough, dispersing stasis, and relieving swelling. Polyphenols and flavonoids contain numerous isomers, which hinder the identification of the complex compounds in BFH. This paper presents a systematic protocol for studying chemical constituents of BFH based on solvent extraction and integrated data via UPLC-Q-TOF-MS.
The method described here includes systematic protocols for sample pretreatment, MS calibration, MS acquisition, data processing, and analysis of results. Sample pretreatment includes collection, cleaning, drying, crushing, and extraction. MS calibration consists of multipoint and single-point correction. Data processing includes data importing, method establishment, analysis processing, and result presentation. Representative results of the typical fragmentation pattern of phenolic acids, esters, and glycosides in Gynura bicolor DC. (BFH) are presented in this paper. In addition, organic solvent selection, extraction, data integration, collision energy selection, and method improvement are discussed in detail. This universal protocol can be widely used to identify complex compounds in TCM.

We describe a general protocol that integrates high-resolution mass spectrometry analysis and molecular docking in traditional Chinese medicine research.

The separation and analysis of the desired chemical components are important subjects for the fundamental research of traditional Chinese medicine (TCM). ...

科研

化学

To begin, prepare 0.5 millimolar sodium formate solution. Once the UPLCQOFMS control software is launched, open the MS tune window in the sample flow control panel set 25 microliters per minute in the infusion flow rate option, select C in the reservoir option, and wait about one minute for the automatic purge to end. Next click flow to start delivering sodium formate solution.Click on the positive button to switch to the positive ion mode and click on the sensitivity button to switch to the sensitivity mode. Then open the MS console window, select synapse access and IntelliStart options in sequence. Click on create calibration, and click on the start button.Click on the next button and select calibration profile in the dropdown menu. After clicking next, select the sensitivity mode in positive polarity. Then sequentially click on the next, tune page, next, and start buttons.Switch to the MS tune window and click the negative button to switch to the negative ion mode. In the MS console window, tick create calibration, then click start. Click on next.Select calibration profile and select the sensitivity mode in negative polarity. Again, click on next, tune page, next, and start buttons. Next in the lock spray flow control panel, set the flow rate to 50 microliters per minute and click on the flow button to allow the LE solution to enter the mass spectrometer.Switch to the MS tune window. Tick the lock spray source setup, and click on the start button to begin calibration. For MS acquisition, switch to the main interface and right click on the inlet file column to open the liquid chromatography method.Click on the inlet button and set parameters such as runtime and gradient. Then click the auto sampler button and set parameters including runtime, column, and sample, and click on save. Next, right click on the MS method column to open the mass spectrometry method.Under information set parameters including end time, polarity, analyzer mode, low mass, high mass, and ramp transfer collision energy. Click okay and then save. Then fill in the sequence table with the file name vial and volume.Save the sequence, select the sample to run from the sequence table and initiate the run.

Processing and Analysis of Mass Spectrometry Data for Chemical Composition Analysis of Gynura bicolor DC

After launching the data analysis software, go to the my work column and click on import mass links data to open a new window. Click on the plus sign and select all five raw files from the positive mode acquired by high resolution mass spectrum metric analysis. Enter a group name and click on create unify sample set to start data import.Double click on the analysis method file in the positive mode. Click on processing, followed by the target by mass button. Enter 5PPM for target match tolerance and fragment match tolerance.Click on home, and then adducts. Select the rows of protylated and acetylated. Click on the right arrow-shaped button, and then save.In the my work column, click on analysis. Choose the imported data and method, and then click on next. Enter the file name, select the folder for storing the analysis data, and click finish.Then, click on the process button. Copy the result table into a blank form for analysis. Next, select a compound in the result table.The corresponding secondary mass spectrum will appear in the lower right corner. Click on the table-shaped button, and select the high energy fragments option to display the table of secondary fragment ions. Select a secondary fragment ion in the table.Move the cursor over the ion peak corresponding to the secondary mass spectrum, and the corresponding structural fracture will be displayed. Manually draw the fragmentation pattern in a drawing software. The chemical composition identification of BFH revealed 168 compounds based on the compound results of six extractants.To understand the cleavage pathway in UPLC-TOF-MS for acids, 3-O-trans-coumaroylquinic acid was demonstrated. Cleavage via hydrolysis reaction led to the formation of intermediates. For esters, trans-O-glucosyl-methyl-trans-cinnamate showed conversion into intermediates via carbon-carbon cleavage.For glycosides cintrucin C transformed into an intermediate via carbon-carbon bond cleavage in the alphalytic chain, or via the breakage of the carbon oxygen carbon bond on the benzene ring. Gene ontology enrichment analysis showed the probable gene functions of the identified compounds. Also, the KEGG pathway annotation analysis showed the pathways for differentially expressed genes.