Offline two-dimensional liquid chromatography coupled with ion mobility-quadrupole time-of-flight mass spectrometry enabling fourdimensional separation and characterization of the multicomponents from white ginseng and red ginseng

Inherent complexity of plant metabolites necessitates the use of multi-dimensional information to accomplish comprehensive profiling and confirmative identification.A dimension-enhanced strategy,by offline two-dimensional liquid chromatography/ion mobility-quadrupole time-of-flight mass spectrometry(2 D-LC/IM-QTOF-MS)enabling four-dimensional separations(2 D-LC,IM,and MS),is proposed.In combination with in-house database-driven automated peak annotation,this strategy was utilized to characterize ginsenosides simultaneously from white ginseng(WG)and red ginseng(RG).An offline 2 DLC system configuring an Xbridge Amide column and an HSS T3 column showed orthogonality 0.76 in the resolution of ginsenosides.Ginsenoside analysis was performed by data-independent high-definition MSE(HDMSE)in the negative ESI mode on a Vion?IMS-QTOF hybrid high-resolution mass spectrometer,which could better resolve ginsenosides than MSEand directly give the CCS information.An in-house ginsenoside database recording 504 known ginsenosides and 58 reference compounds,was established to assist the identification of ginsenosides.Streamlined workflows,by applying UNIFI?to automatedly annotate the HDMSEdata,were proposed.We could separate and characterize 323 ginsenosides(including 286 from WG and 306 from RG),and 125 thereof may have not been isolated from the Panax genus.The established 2 D-LC/IM-QTOF-HDMSEapproach could also act as a magnifier to probe differentiated components between WG and RG.Compared with conventional approaches,this dimensionenhanced strategy could better resolve coeluting herbal components and more efficiently,more reliably identify the multicomponents,which,we believe,offers more possibilities for the systematic exposure and confirmative identification of plant metabolites.

Establishing a protein expression profile database for the normal human pituitary gland using two-dimensional high-performance liquid chromatography combined with LTQ-Orbitrap mass spectrometry

In this study, we selected adult normal pituitary gland tissues from six patients during operations for pituitary microadenomas via the transsphenoidal approach for extended normal pituitary tissue resection around the tumor, and analyzed the protein expression of human normal pituitary using two-dimensional high-performance liquid chromatography combined with LTQ-Orbitrap mass spectrometry proteomics technology. The ten most highly expressed proteins in normal human pituitary were： alpha 3 type VI collagen isoform 5 precursor （abundance among tall pituitary proteins 1.30%）, fibrinogen beta chain preproprotein （0.99%）, vimentin （0.73%）, prolactin （0.69%）, ATP synthase, H~ transporting and mitochondrial F1 complex beta subunit precursor （0.52%）, keratin I （0.49%）, growth hormone （0.45%）, carbonic anhydrase I （0.40%）, heat shock protein 90 kDa I （0.31%）, and annexin V （0.30%）. Based on the biological function classifications of these proteins, the top three categories by content were neuroendocrine proteins （abundance among all pituitary proteins, 40.1%）, catalytic and metabolic proteins （28.3%）, and cell signal transduction proteins （9.8%）. Based on cell positioning classification, the top three categories were cell organelle （24.5%） membrane （20.8%）, and cytoplasm （13.0%）. Based on biological process classification, the top three categories of proteins are involved in physiological processes （42.9%）, cellular processes （40.4%）, and regulation of biological processes （9.1%）. Our experimental findings indicate that a protein expression profile database of normal human pituitary can be precisely and efficiently established by proteomics technology.

Using cell membrane chromatography and HPLC-TOF/MS method for in vivo study of active components from roots of Aconitum carmichaeli

An offline two-dimensional system combining a rat cardiac mascle cell membrane chromatography time-of-flight mass spectrometry （CMC-TOF/MS） with a high performance liquid chromatography time-of-flight mass spectrometry （HPLC-TOF/MS） was established for investigating the parent components and metabolites in rat urine samples after administration of the roots of Aconitum carmichaeli. On the basis of the analysis of the first dimension, retention components of the urine sample were collected into 30 fractions （one fraction per minute）. Then offline analysis of the second dimension was carried out. 34 compounds including 24 parent alkaloids and 10 potential metabolites were identified from the dosed rat urine, and then binding affinities of different compounds on cell membranes were compared and influences of some functional groups on activity were estimated with the semi-quantification and curve fitting method. As a result, binding affinities decreased along with the process of deacylation, debenzoylation and demethylation, which may be related to the alleviation of toxicity in the procedure of herb processing or metabolism. Moreover, some minor components in rat urine （Songorine, 14-benzoylneoline, Deoxyaconitine, etc. ） exerted relatively strong affinity on cell membranes are worth exploring. The results delivered by the system suggest that the CMC can be applied to in vivo study.

On-line parallel reversed phase two-dimensional liquid chromatography for high-throughput analysis of complex proteomic samples

A comprehensive two-dimensional liquid chromatographic system (2D SCX/RP) is con- structed with a 10-port-2-way valve using strong cation exchange chromatography (Hypersil SCX, 100 mm×4.6 mm I.D.) followed by reversed phase chromatography (Hypersil BDS C18, 15 mm×4.6 mm I.D.) to separate the complex peptides from globin peptic hydrolysate. After the sample was loaded on the SCX column, the phosphate buffer (pH 4.0) was used to elute the peptides. Then, elutes flowed through the interface and the peptides focused on the head of the trapping columns (Hypersil BDS C18, 15 mm×4.6 mm I.D.) but salt passed into the waste. After the valve was switched, the samples were flushed with a backward flow into the RP analytical column. The peptides on the SCX were eluted with 12 discontinuous steps linearly increasing salt concentrations. The peptides enriched on the trapping column were desalted and separated by the RP columns. The resolution and the resolved peaks of the 2D SCX/RP system were greatly increased and the total peak capacity reached as high as 2280.

Double Off-line Two-dimensional Liquid Chromatography for Separation and Identification of Compounds in Salvia Miltiorrhiza(Danshen)

Background: Danshen is an important traditional Chinese medicine(TCM) used for the treatment of cardiovascular and cerebrovascular diseases. Separation and analysis of its components have been widely investigated. However, the systematical two dimensional liquid chromatography(2D-LC) methods have not been developed to comprehensively separate and characterize its components.Objective: In this work, double off-line 2D-LC methods were aimed to develop for the systematical separation of compounds from Danshen.Methods: Using solid phase extraction(SPE), the Danshen extract was divided into a medium-polar fraction(Sample I) and a weak-polar fraction(Sample Ⅱ) according to their polarities. Based on reversed-phase liquid chromatography(RPLC) and hydrophilic interaction liquid chromatography(HILIC) modes, a 2D-HILIC × RPLC system and a 2D-RPLC × RPLC system were designed for the separation of Sample Ⅰ and Sample Ⅱ, respectively. According to reversed-phase and HILIC columns selectivities characterized in our previous reports, ZIC-HILIC and XTerra C18 were employed to build the 2D-HILIC × RPLC system and Click TE-CD and XTerra C18 for the 2D-RPLC × RPLC system,respectively.Results: The 2D-HILIC × RPLC and 2D-RPLC × RPLC systems exhibited excellent orthogonality for the separation of Sample Ⅰ and Sample Ⅱ,respectively. Their orthogonalities were 88.42% and 63.24%. Based on these double 2D-LC systems combined with mass spectrometry, at least 200 compounds were found and 33 compounds of them were identified, including 16 phenolic acids and 17 diterpenoid quinines.Conclusion: These results suggest that these two off-line 2D-LC methods are effective for the separation and characterization of components in Danshen.

COMPREHENSIVE TWO-DIMENSIONAL LIQUID CHROMATOGRAPHY COUPLED WITH QUADRUPLE TIME-OF-FLIGHT MASS SPECTROMETRY FOR CHEMICAL CONSTITUENTS ANALYSIS OF TRIPTERYGIUM GLYCOSIDES TABLETS

Comprehensive two-dimensional liquid chromatography platform(LC×LC)coupled with quadrupole time-of-flight(QTOF)mass spectrometry(MS)is developed to separate,identify and relatively determine the chemical constituents of two types of tripterygium glycosides tablets(TGT).The types and relative contents of the constituents discovered in two kinds of TGT tablets were subsequently compared.C8andC18 column were used for the separation of the first

An Automatic Solid Phase Extraction and Ultra-Performance Liquid Chromatography Tandem Mass Spectrometry for Determination of Seven Microcystins at Ultra-Trace Levels in Surface Water

A method was developed for the detection of seven microcystins(microcystin-LR, RR, YR, LA, LY, LW and LF) in surface water using automatic solid-phase extraction(A-SPE) coupled with ultra-performance liquid chromatography tandem mass spectrometry(UPLC-MS/MS). The automated solid-phase extraction system was used to extract microcystins(MCs) from water samples. UPLC-MS/MS was used to determine MCs concentrations in just 5 min. Method detection limits were from 0.3 to 0.9 ng/L, microcystin recoveries ranged from 83.8% to 114%, and the relative standard deviation(RSD) varied from 5.6% to 12.5%. This analytical approach was found to be simple, highly sensitive, accurate, which required little manual operation. Additionally, to validate this analytical method, A-SPE+UPLC-MS/MS was applied to characterize the concentration of MCs in Taihu Lake, Wuxi, China.

Ion-pair Reversed-phase×Low-pH Reversed-phase Two-dimensional Liquid Chromatography for In-depth Proteomic Profiling

High-resolution liquid chromatography separation is essential to in-depth proteomic profiling of complex biological samples.Herein,we established an ion-pair reversed-phase×reversed-phase two-dimensional liquid chromatography(IPRP×RP 2DLC)strategy for comprehensive proteomic analysis.Both RPLC separation dimensions were performed at low pH,with trifluoroacetic acid(TFA)and formic acid(FA)as mobile phase addictive,respectively.As the good separation resolution offered by ion-pairing effect of TFA,the fractionation efficiency was greatly improved with 74.0%peptides identified in just one fraction.Comparing with conventional high pH RP fractionation,the overall separation rate of IPRP was about 1.6 times that of high-pH RP,which increased the number of identified peptides by 21%.Further,2169 proteins and 8540 peptides were confidently identified from crude serum sample by our IPRP×RP 2DLC strategy,exhibiting great potential in clinical proteomics in the future.

TWO-DIMENSIONAL LIQUID CHROMATOGRAPHY(2D-LC) IN THE ANALYSIS OF PHARMACEUTICALS AND AUTHENTICATION OF CHINESE HERBAL MEDICINE

One-dimensional liquid chromatography(1D-LC)is routinely applied to the analysis of all kinds of samples in different fields.With the introduction of UHPLC instruments and sub-2micron particle columns,the separation efficiency was greatly improved.To resolve all components of complex samples,however,1D-LC does not provide enough resolving power,or peak capacity.In addition,to separate compounds co-eluting in 1D-LC,increasing the separation efficiency by increasing

全自动固相萃取—高效液相色谱法测定现制饮料中7种合成着色剂

目的:建立一种全自动固相萃取—高效液相色谱双波长法测定现制饮料中7种合成着色剂的方法。方法:样品经纯水提取2次,离心后,合并上清液,调节pH至3~4。利用全自动固相萃取装置活化Poly-sery色素专用固相萃取小柱,并上样、淋洗、洗脱。洗脱液氮吹浓缩至200μL,用50%流动相A+50%流动相B混合液定容至1.0 mL。色谱柱采用C 18柱,流动相为20 mmol/L乙酸铵—甲醇,梯度洗脱,流速1.0 mL/min,进样量10μL,检测波长254,628 nm。结果:各物质在0.5~50.0μg/mL范围内相关系数均大于0.9999,方法检出限为0.023~0.179 mg/kg,定量限为0.078~0.598 mg/kg,加标回收率为92.4%~96.8%,相对标准偏差(RSD)为1.2%~4.2%。结论:该方法试剂使用量小,操作步骤简便,自动化程度高,回收率高,重复性好,适合于批量样品测定。

自动QuEChERS结合UPLC-MS/MS测定莲雾中苯并咪唑类农药残留

为了建立自动QuEChERS结合高效液相色谱-串联质谱法测定莲雾中多菌灵、噻菌灵、苯菌灵及甲基硫菌灵4种苯并咪唑类农药残留量的检测方法。将莲雾样品采用混合试剂(5.5 g硫酸镁+1.5 g氯化钠+1.0 g柠檬酸钠+0.5 g柠檬酸二钠)进行净化,经QuEChERS自动样品制备系统进行制备后,应用超高效液相色谱-三重四级杆串联质谱法进行分析。结果表明,4种农药在1.00~10.00 ng/mL质量浓度范围内线性关系良好,决定系数(R2)均大于0.99;0.1、1.0、5.0 mg/kg 3个添加水平下,在莲雾基质中添加回收率为84%~105%,相对标准偏差为0.8%~9.5%(n=3),方法检出限和定量限分别为0.1~0.5μg/kg和0.5~10.0μg/kg。综上,该方法简便省时,净化效果好,灵敏度及准确度高,可用于同时测定莲雾中多菌灵、噻菌灵、苯菌灵及甲基硫菌灵4种苯并咪唑类农药的残留量。

全自动二维液相色谱测定人血清中阿普唑仑浓度及其临床应用

目的建立一种简便、快速、准确测定人血清中阿普唑仑浓度的分析方法,供临床治疗药物监测使用。方法将样本去除蛋白后采用二级单工方法检测,第一维萃取柱为Aston SC2(3.5 mm×25 mm,5μm),流动相为NCD-1D(甲醇-乙腈-磷酸铵缓冲液=13.5∶16.5∶70,V/V/V),流速为0.8 mL·min^(-1);捕获柱为Aston SH(3.5 mm×10 mm,5μm);第二维分析柱为Aston SN(4.6 mm×125 mm,5μm),流动相为乙腈-磷酸铵(氨水调pH 7.4)-甲醇(18∶32∶50,V/V/V),流速为1.2 mL·min^(-1)。紫外检测波长286 nm和261 nm,柱温为40℃,进样量为500μL。建立了全自动二维液相色谱仪测定人血清中阿普唑仑的方法,并对该方法学进行了验证。结果人血清中阿普唑仑在5.00~100.04 ng·mL^(-1)与峰面积线性关系良好,标准曲线为y=6.423×10^(3)x-2.617×10^(3)(r=0.9998),定量下限为5.00 ng·mL^(-1),日内精密度RSD≤6.2%,日间精密度RSD≤9.7%。低、中和高质量浓度的回收率在96.2%~100.7%,样品在所有考察的条件下均稳定。结论本研究建立的分析方法准确性高、稳定性强,简便快捷,自动化程度高,可为临床阿普唑仑血药浓度监测、中毒患者的药物筛查以及阿普唑仑个性化给药提供实验依据。

全自动QuEChERS-超高效液相色谱-串联质谱法测定花类代用茶中链格孢霉毒素

本文建立了全自动Qu ECh ERS-超高效液相色谱-串联质谱法快速测定花类代用茶中5种链格孢霉毒素的分析方法。样品经全自动Qu ECh ERS前处理,以ACQUITY UPLCHSST3色谱柱分离,在电喷雾离子源负源模式下,进行多反应监测分析。在优化后的条件下,5种链格孢霉毒素在各自的线性响应范围内线性关系良好,相关系数(r)均大于0.999,在6种花类代用茶基质的3个不同加标水平下平均回收率为82.3%~105.7%,相对标准偏差(RSD)小于10%,方法检出限为0.5~1.5μg/kg。方法具有分析速度快、稳定性好、灵敏度高的特点,能够满足花类代用茶中链格孢霉毒素的快速检测需求。

高通量高效快速净化方法结合UPLC-MS/MS测定粮食中黄曲霉毒素

建立粮食中黄曲霉毒素B1、B2、G1、G2快捷高效的确证检测方法。通过对色谱及质谱分析条件、震荡提取方式、稀释倍数分别优化确定满足黄曲霉毒素B1、B2、G1、G2检测方法的最优条件,同时,开发一款自动过柱仪与快速净化柱配合使用对粮食中杂质进行高通量的高效净化,并采用超高效液相色谱-串联质谱(UPLC-MS/MS)进行检测分析。粮食样品经84%乙腈水溶液提取、Speedy Prep®-Myco1流穿式净化柱净化,使用ACQUITY UPLC BEH C18色谱柱分离,以0.1%甲酸水和乙腈作为流动相进行梯度洗脱,质谱采用电喷雾正离子模式和多反应监测模式(multiple reaction monitoring,MRM)采集信号,外标法定量。对于大米、小黄米、小麦、黄豆、面粉、大麦、黑米、花生、玉米基质,本方法黄曲霉毒素B1、B2、G1、G2的检出限和定量限分别为0.06~0.12μg/kg和0.20~0.40μg/kg,在其线性范围内相关系数R≥0.9993,在0.2、0.4、1、10、20、40μg/kg添加回收率为72.37%~118.4%,相对标准偏差(RSD,n=6)为0.64%~14%,回收率和精密度良好。该方法前处理操作简单、稳定性好,适用于粮食中黄曲霉毒素B1、B2、G1、G2的检测。

液液萃取/气相色谱-质谱法结合自动解卷积-Kováts保留指数法定性分析电子烟液中的挥发性成分

基于液液萃取/气相色谱-质谱法结合自动解卷积-Kováts保留指数法,建立了电子烟液中挥发性成分的检测方法。对提取溶剂种类进行了优化,并依据烟液中香气成分的香气特征,分析果味和烟草味烟液的香韵构成和差异,确定不同果味烟液的特征香气成分。结果表明:①以乙醚为提取溶剂能减弱丙三醇对其他组分识别的干扰。②自动解卷积法能准确识别共流出组分和低含量组分;Kováts保留指数法提升了化合物识别的准确度。③在10种烟草味烟液中检出15种成分,以豆香、焦香香韵化合物为主;在21种果味烟液中检出80种成分,以果香、花香香韵化合物为主,确定了16类果味烟液的特征香气成分。通过随机验证实验,该方法可有效分辨不同果味类型的果味烟液和烟草味烟液。该方法样品用量少、前处理过程简单、样品分析用时短,能满足烟液中香气成分的检测需要,可为果味电子烟液的检验识别和监管提供参考。

全自动加速溶剂萃取-超高效液相色谱-串联质谱法测定土壤中7种杀线虫剂的残留量

通过优化提取、净化条件,提出了题示方法测定土壤样品中棉隆、噻唑膦、灭线磷、丰索磷、杀线威、丁硫环磷、除线磷等7种杀线虫剂的含量。随机采集土壤样品,风干,粉碎后过筛,分取10.0 g,加入硅藻土15.0 g,用体积比2:1的甲醇和三氯甲烷混合溶液进行加热加压全自动萃取;萃取液过活化好的HLB固相萃取柱,用10 mL体积比1∶1的甲醇和乙腈混合溶液洗脱。洗脱液于45℃氮吹至近干,残留物用1 mL乙酸乙酯溶解,过0.22μm滤膜,滤液采用超高效液相色谱-串联质谱法测定。结果显示:7种杀线虫剂的质量浓度在0.005~2.0 mg·L^(-1)内与峰面积呈线性关系,检出限(3S/N)为4~25μg·kg^(-1);按照标准加入法进行回收试验,回收率为87.2%~101%,测定值的相对标准偏差(n=6)为1.5%~3.8%;方法用于实际样品分析,检出了棉隆、噻唑膦、灭线磷、丰索磷、除线磷,检出量为14.81~124.03μg·kg^(-1)。

全自动QuEChERS净化-高效液相色谱-串联质谱法测定作物土壤中3种抗菌素类杀菌剂的残留量

提出了全自动QuEChERS净化-高效液相色谱-串联质谱法(HPLC-MS/MS)测定作物土壤中春雷霉素、多抗霉素、布拉叶斯等3种抗菌素类杀菌剂残留量的方法。将作物土壤样品用粉碎机粉碎,于-18℃储存。取25 g处理后的作物土壤样品,置于QuEChERS自动样品制备系统配备的样品管中,分别加入1粒陶瓷均质子、20 mL 85%(体积分数)甲醇溶液、QuEChERS提取包、内置管(含净化剂),以转速2 000 r·min^(-1)振荡5 min,以转速6 000 r·min^(-1)离心5 min。移取2 mL净化液置于试管中,于50℃氮吹至近干,加入1 mL甲醇复溶,过0.22μm滤膜,采用HPLC-MS/MS测定滤液中3种抗菌素类杀菌剂的含量。以Waters BEH ODS C_(18)色谱柱为固定相,以不同体积比的0.1%(体积分数)甲酸溶液-乙腈混合液为流动相进行梯度洗脱,质谱分析采用电喷雾离子(ESI)源,在正离子(ESI^(+))扫描模式下进行多反应监测(MRM)模式分析。结果表明,3种抗菌素类杀菌剂的质量浓度在0.005~0.5 mg·L^(-1)内与对应的定量离子响应值呈线性关系,检出限(3S/N)为0.10~0.13μg·kg^(-1)。按照标准加入法进行回收试验,回收率为83.2%~106%,测定值的相对标准偏差(n=6)均小于5.0%。方法用于测定实际作物土壤中3种抗菌素类杀菌剂的残留量,检出量为10.11~59.07μg·kg^(-1)。

全自动固相萃取-高效液相色谱-串联质谱法测定耕地周边地表水中6种嘧啶类杀菌剂的残留量

提出了全自动固相萃取-高效液相色谱-串联质谱法测定耕地周边地表水中乙嘧酚、嘧菌环胺、氟嘧菌胺、嘧菌腙、嘧霉胺、氯苯嘧啶醇等6种嘧啶类杀菌剂残留量的方法。分取预处理后的地表水样品500 mL,调节酸度至pH(7.00±0.05),以18 mL·min^(-1)流量过活化好的HLB固相萃取柱(500 mg/12 mL),用体积比1:1的甲醇-乙腈混合溶液洗脱,收集洗脱液,于45℃氮吹至近干,加入甲醇1 mL复溶,涡旋混匀后上机检测。结果表明:6种嘧啶类杀菌剂的质量浓度均在0.01~5.00μg·mL^(-1)内与对应的质谱响应值呈线性关系,检出限(3S/N)为0.007~0.033μg·L^(-1);按照标准加入法进行回收试验,回收率为84.8%~102%,测定值的相对标准偏差(RSD,n=5)为1.5%~3.6%,重复性RSD(n=6)为1.9%~2.9%。

全自动垂直振荡提取-超高效液相色谱-串联质谱法测定鱼肉中地西泮残留量

建立全自动垂直振荡提取-超高效液相色谱-串联质谱法测定鱼肉中地西泮残留量。采用乙腈作为样品提取溶剂,全自动垂直振荡提取,MCX固相萃取法净化。选取SB-C18色谱柱(2.1 mm×50 mm,1.8μm)分离,以0.1%(体积分数)甲酸水和乙腈作为流动相分离,在电喷雾正离子模式和多反应监测模式下检测,外标法定量。结果表明,地西泮的质量浓度在0.1~50.0 ng/mL范围内与色谱峰面积线性关系良好,相关系数为0.9998,方法检出限为0.1μg/kg,定量限为0.3μg/kg。在低、中、高3个浓度加标水平下,地西泮的平均回收率为75.6%~88.6%,测定结果的相对标准偏差为2.2%~4.8%(n=7)。该方法提取效率高,净化效果好,降低了样品基质干扰,提高了方法准确性,可用于鱼肉中地西泮残留量的大批量检测。

全自动加速溶剂萃取结合固相萃取-高效液相色谱-串联质谱法测定果树种植土壤中3种喹啉类杀菌剂的残留量

提出了全自动加速溶剂萃取结合固相萃取-高效液相色谱-串联质谱法(HPLC-MS/MS)测定果树种植土壤中灭螨猛、二氰蒽醌、乙氧喹啉等3种喹啉类杀菌剂残留量的方法。取预处理后的土壤样品粉末10.0 g,加入硅藻土约10 g,混匀后置于加速溶剂萃取池中,在萃取温度70℃,萃取时间8 min下进行萃取,得到的提取液氮吹至5 mL,然后用活化好的HLB固相萃取柱进行净化。经过淋洗、洗脱后,将洗脱液氮吹至近干,用乙腈定容至1 mL,过0.45μm滤膜。采用HPLC-MS/MS测定滤液中3种喹啉类杀菌剂的含量。以Shimadzu Venusil MP C_(18)色谱柱为固定相,以不同体积比的0.1%(体积分数)甲酸溶液和甲醇混合溶液为流动相进行梯度洗脱;分离后的目标物经电喷雾离子源正离子模式扫描,多反应监测模式检测。结果表明:3种目标物的质量浓度均在一定范围内与对应的响应值呈线性关系,检出限(3S/N)为0.05~0.13μg·kg^(-1);3个加标浓度水平下,目标物的回收率为87.3%~103%,测定值的相对标准偏差(n=6)均小于4.0%。