Multicomponent Characterization of the Flower Bud of Panax notoginseng and Its Metabolites in Rat Plasma by Ultra-High Performance Liquid Chromatography/Ion Mobility Quadrupole Time-of-Flight Mass Spectrometry

The flower bud of Panax notoginseng (PNF) consumed as a tonic shows potential in the prevention and treatment of cardiovascular diseases. To identify the contained multi-components and, in particular, to clarify which components can be absorbed and what metabolites are transformed, unveiling the effective substances of PNF is of vital significance. A unique ultrahigh-performance liquid chromatography/ion mobility quadrupole time-of-flight mass spectrometry (UHPLC/IM-QTOF-MS) profiling approach and efficient data processing by the UNIFI^TM bioinformatics platform were employed to comprehensively identify the multi-components of PNF and the related metabolites in the plasma of rats after oral administration (at a dose of 3.6 g/kg). Two MS² data acquisition modes operating in the negative electrospray ionization mode, involving high-definition MS^E (HDMS^E) and data-dependent acquisition (DDA), were utilized aimed to extend the coverage and simultaneously ensure the quality of the MS² spectra. As a result, 219 components from PNF were identified or tentatively characterized, and 40 thereof could be absorbed. Moreover, 11 metabolites were characterized from the rat plasma. The metabolic pathways mainly included the phase I (deglycosylation and oxidation). To the best of our knowledge, this is the first report that systematically studies the in vivo metabolites of PNF, which can assist in better understanding its tonifying effects and benefit its further development.     

邓老凉茶颗粒的超高效液相色谱质谱联用指纹图谱研究

建立了适用于邓老凉茶颗粒质量控制的超高效液相色谱质谱联用指纹图谱分析方法。样品采用甲醇索氏萃取60 min,萃取液采用超高效液相色谱质谱法进行指纹图谱分析。色谱柱采用Waters ACQUITY HSST3 C18(150 mm×3.0 mm,1.8μm),以0.5%甲酸-乙腈为流动相进行梯度洗脱,流速为0.8 mL/min,柱温35℃。质谱采用负离子ESI模式,选择基峰离子流质量色谱图进行指纹图谱研究。32个共有峰在15 min内得到良好分离,其中15个共有峰通过对照品进行了确证。通过《中药色谱指纹图谱相似度评价系统2004A版》对邓老凉茶颗粒样品进行相似度分析,15个批次样品的相似度均达到0.960以上,表明邓老凉茶颗粒的产品质量稳定性很好。以32个共有峰的相对峰面积进行主成分分析,邓老凉茶颗粒样品之间的细微质量差异得到明显区分。该方法快速、高效、可靠,可有效地用于邓老凉茶颗粒的质量控制。     

高效液相色谱-四极杆/离子阱质谱确证测定面粉及面制品中氨基脲

采用高效液相色谱-四极杆/离子阱质谱(HPLC-QTRAP-MS)建立了面粉及面制品中氨基脲的确证及测定方法。样品采用盐酸(HCl)提取,在超声辅助下与衍生剂邻硝基苯甲醛反应。衍生产物在中性条件下经PLS固相萃取柱净化、乙酸乙酯洗脱,经Shim-Pack XR-ODSⅢC18柱(2.0 mm×50 mm,1.6μm)分离,0.1%(体积比)甲酸-水溶液和甲醇溶液为流动相梯度洗脱;采用多反应监测(MRM)-信息依赖性采集(IDA)-增强子离子扫描(EPI)模式检测,EPI谱库确认,内标法定量。结果表明:氨基脲在0.5~40μg/L范围内线性关系良好(r=0.996);检出限(LOD,S/N=3)为0.10μg/kg,定量下限(LOQ,S/N=10)为0.25μg/kg;4个加标水平(0.25,0.5,2.0,10.0μg/kg)下的回收率为89.1%~112.8%;相对标准偏差(RSD)为1.4%~8.6%。该方法分析速度快,灵敏度高,回收率好,可用于面粉及面制品中氨基脲的快速检测。     

液相色谱-四极杆/离子阱质谱快速测定蜂蜜中痕量硝基咪唑类药物及其代谢物残留

采用液相色谱-四极杆/离子阱串联质谱(LC-QTRAP)建立了蜂蜜中痕量硝基咪唑类药物(甲硝哒唑、咯硝哒唑、二甲硝咪唑、异丙硝唑)及其羟基代谢物(2-羟甲基-1-甲基-5-硝基咪唑、羟基甲硝唑和羟基异丙硝唑)残留的快速测定方法。样品经磷酸盐缓冲液(0.5 mol/L,pH 8.8)/乙酸乙酯提取,高速冷冻离心净化;C18柱色谱分离,流动相为0.1%甲酸水溶液-甲醇,梯度洗脱;质谱采集使用预设定多反应监测(sMRM)-信息依赖性采集(IDA)-增强子离子扫描(EPI)模式;目标分析物使用同位素内标定量,在线EPI谱库辅助定性。7种目标分析物在0.125～50.0μg/L范围内线性关系良好(r>0.999);定量下限(LLD)均达到0.1μg/kg;1LLD、2LLD和4LLD 3个加标水平的回收率为94%～108%;相对标准偏差(RSD)均不大于11.4%。     

超高效液相色谱-高分辨四级杆飞行时间质谱法快速筛查乳制品中磺胺类与氟喹诺酮类药物

利用超高效液相色谱-高分辨四级杆飞行时间质谱联用技术,建立了一种快速筛查乳制品中8种氟喹诺酮5种磺胺类药物及其4种乙酰化代谢物的新方法。采用乙腈-20%三氯乙酸溶液(100∶1,V/V,pH 2.0)作溶剂和Oasis HLB固相萃取载体作吸附剂,实现了牛奶样品中17种目标物的同时提取和有效净化。利用MassLynx Chromlynx软件建立了这17种分析物的数据库。以Full Scan/MSE进行定性筛查和定量检测。4种代谢物在10~2000μg/L范围内和其它分析物在0.5~100μg/L范围内,其基质匹配内标校准曲线呈现良好的线性(R2>0.983)。氟喹诺酮的定量限为0.5~0.8μg/kg,磺胺类药物及代谢物的定量限为0.5~13.0μg/kg。在3个添加水平分析物的平均回收率(69%~92%)在职业分析化学家协会(AOAC)提出的允许范围之内,相对标准偏差均小于15%。本方法快速而灵敏,成功用于乳制品中抗生素及其代谢物的筛查、确认和定量分析。所研究的每种药物及代谢物残留均低于有关的最高残留限量(MRLs),但某些乳制品中其总残留量已超过最高残留限量。     

超高效液相色谱三重四极杆质谱联用法快速检测尿液和血浆中鹅膏毒肽和鬼笔毒肽

建立了同时快速检测尿液和血浆中3种鹅膏毒肽和2种鬼笔毒肽的超高效液相色谱三重四极杆质谱联用分析方法。尿液样品直接进样,血浆样品经乙腈沉淀除蛋白后,在UPLCHSST3色谱柱上分离,正离子电喷雾多反应监测(MRM)模式检测,基体匹配标准外标法定量。尿液和血浆样品的线性范围分别为2～100和1～100μg/L;加标回收率分别在92.0%～108.0%和85.0%～100.0%的范围内;相对标准偏差为1.0%～22.0%和2.0%～22.0%(n=6);样品的检出限为0.2～1.0μg/L和0.1～0.5μg/L(S/N=3)。本方法灵敏,简单,快速,特异性强。     

在线固相萃取-超高效液相色谱-线性离子阱串联质谱法直接测定水中10种藻类毒素

建立了全自动在线固相萃取-超高效液相色谱-线性离子阱串联质谱法直接测定水中10种藻类毒素的方法.利用程序实现多次进样,通过在线固相萃取对藻类毒素进行富集,然后切换六通阀,将富集的目标物冲洗至分析柱进行分离后,进入线性离子阱质谱检测.10种藻类毒素在相应的浓度范围内线性关系良好,相关系数均大于0.99,检出限在0.0015~0.0050μg/L之间,3个浓度水平(0.02、0.10和1.00μg/L)的加标回收率为83.7%~98.5%.结果表明,在线固相萃取极大简化了前处理过程,线性离子阱串联质谱法提高了痕量藻类毒素测定的灵敏度,增强子离子扫描(EPI)谱库的建立为藻类毒素的确证提供保障.本方法适用于水体中多种藻类毒素的快速确证和定量测定.     

Integrating Enhanced Profiling and Chemometrics to Unveil the Potential Markers for Differentiating among the Leaves of Panax ginseng,P. quinquefolius,and P. notoginseng by Ultra-High Performance Liquid Chromatography/Ion Mobility-Quadrupole Time-of-Flight Mass Spectrometry

The leaves of Panax species (e.g., Panax ginseng-PGL, P. quinquefolius-PQL, and P. notoginseng-PNL) can serve as a source for healthcare products. Comprehensive characterization and unveiling of the metabolomic difference among PGL, PQL, and PNL are critical to ensure their correct use. For this purpose, enhanced profiling and chemometrics were integrated to probe into the ginsenoside markers for PGL/PQL/PNL by ultra-high performance liquid chromatography/ion mobility-quadrupole time-of-flight mass spectrometry (UHPLC/IM-QTOF-MS). A hybrid scan approach (HDMS^E-HDDDA) was established achieving the dimension-enhanced metabolic profiling, with 342 saponins identified or tentatively characterized from PGL/PQL/PNL. Multivariate statistical analysis (33 batches of leaf samples) could unveil 42 marker saponins, and the characteristic ginsenosides diagnostic for differentiating among PGL/PQL/PNL were primarily established. Compared with the single DDA or DIA, the HDMS^E-HDDDA hybrid scan approach could balance between the metabolome coverage and spectral reliability, leading to high-definition MS spectra and the additional collision-cross section (CCS) useful to differentiate isomers.