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1.
苏娟  贺亚男  杨鑫  谢慧娟  纪奇森  杨明  张定堃  韩丽 《中草药》2023,54(22):7374-7386
目的 研究阴干、晒干、真空冷冻干燥、热风干燥4种干燥方式对马蓝Baphicacanthus cusia叶化学成分的影响,寻找差异成分,并建立HPLC-DAD同时定量分析5种吲哚类生物碱成分的方法,以期为建立规范的马蓝叶干燥方式提供理论依据。方法 利用UHPLC-Q-Orbitrap HRMS对4种干燥处理的马蓝叶进行定性分析,并结合热图聚类分析(heat map clustering analysis,HCA)、主成分分析(principal component analysis,PCA)和正交偏最小二乘-判别分析(orthogonal partial least squares-discriminant analysis,OPLS-DA)筛选差异成分。结果 共鉴定出67个共有化合物。HCA和PCA将阴干和热风干燥归为一类。OPLS-DA筛选出14个差异成分,多为生物碱类,且呈现出不同的变化规律。HPLC-DAD结果表明,不同干燥方式马蓝叶中的5种吲哚类生物碱含量存在明显差异。其中,热风干燥样品的靛蓝含量最高,靛玉红含量最低;阴干样品的靛红、色胺酮、靛玉红含量最高。结论 不同的干燥方式对马蓝叶的品质有明显影响。热风干燥和晒干有利于吲哚苷水解合成靛蓝,但靛红和靛玉红的含量较低。而阴干和真空冷冻干燥样品的靛蓝含量较低,而靛玉红含量较高。阴干和热风干燥能显著提高马蓝叶药效成分的总含量。建议在初加工马蓝叶时使用阴干或热风干燥,为进一步探究马蓝叶的产地加工方式提供了数据支持,同时也为评估马蓝叶的质量提供了技术支持。  相似文献   
2.
The doping of greyhound dogs with testosterone is done in an attempt to improve their athletic performance, but such doping cannot easily be confirmed, especially in male dogs owing to the natural presence of endogenous testosterone. As testosterone is usually administered as its esters, their direct detection in hair would provide confirmatory evidence of the administration of a pharmaceutical product. This article demonstrates that the use of a liquid chromatography–high resolution mass spectrometry method with heated electrospray ionisation (HESI) combined with the use of amino solid‐phase extraction (SPE) cartridges for sample clean‐up, is suitable for the sensitive determination of propionate, phenyl propionate, isocaproate, decanoate, and enanthate esters of testosterone in greyhound hair. The method is linear over the range, 0.1 μg/kg–10 μg/kg, for all the testosterone esters analysed. The limits of detection (LOD) are 0.05 μg/kg for testosterone phenyl propionate, isocaproate, and decanoate, 0.025 μg/kg for testosterone propionate, and 0.25 μg/kg for testosterone enanthate. This method was applied to hair samples collected from male greyhounds before and after a single administration of a product containing several testosterone esters, each of which could be detected up to 100 days post‐administration. The study also demonstrates that tail hair is the specimen of choice for the analysis of testosterone in dog hair and that washing of dogs does not impact the analysis of testosterone esters in hair. This method may be useful in racing regulation for the detection of illegitimate use of testosterone in all species.  相似文献   
3.
The use of bioactive peptides as a doping agent in both human and animal sports has become increasingly popular in recent years. As such, methods to control the misuse of bioactive peptides in equine sports have received attention. This paper describes a sensitive accurate mass method for the detection of 40 bioactive peptides and two non‐peptide growth hormone secretagogues (< 2 kDa) at low pg/mL levels in horse urine using ultra‐high performance liquid chromatography‐high resolution mass spectrometry (UHPLC/HRMS). A simple mixed‐mode cation exchange solid‐phase extraction (SPE) cartridge was employed for the extraction of 42 targets and/or their in vitro metabolites from horse urine. The final extract was analyzed using UHPLC/HRMS in positive electrospray ionization (ESI) mode under both full scan and data independent acquisition (DIA, for MS2). The estimated limits of detection (LoD) for most of the targets could reach down to 10 pg/mL in horse urine. This method was validated for qualitative detection purposes. The validation data, including method specificity, method sensitivity, extraction recovery, method precision, and matrix effect were reported. A thorough in vitro study was also performed on four gonadotrophin‐releasing factors (GnRHs), namely leuprorelin, buserelin, goserelin, and nafarelin, using the S9 fraction isolated from horse liver. The identified in vitro metabolites have been incorporated into the method for controlling the misuse of GnRHs. The applicability of this method was demonstrated by the identification of leuprorelin and one of its metabolites, Leu M4, in urine obtained after intramuscular administration of leuprorelin to a thoroughbred gelding (castrated horse).  相似文献   
4.
Recombinant human erythropoietin (rHuEPO) belongs to the therapeutic class of erythropoiesis stimulating agents (ESAs) due to its implication in the creation pathway of red blood cells and thus enhancement of oxygenation. Because of this bioactivity, rHuEPO has been considered as a major doping agent in sports competitions for decades. Over the years, doping control laboratories designed several analytical strategies applied to human and animal samples to highlight any misuse. Even though multiple analytical approaches have been reported, none has yet been dedicated to racing camels. Here, we describe an analytical strategy to test camel plasma samples at screening using an ELISA assay and a targeted nano‐liquid chromatography–high‐resolution tandem mass spectrometry for confirmatory analysis. The method was validated and has been successfully applied to post‐race samples, allowing the detection of a positive case of rHuEPO administration.  相似文献   
5.
New psychoactive substances (NPS) are an important issue in clinical/forensic toxicology. 7’N‐5F‐ADB, a synthetic cannabinoid derived from 5F‐ADB, appeared recently on the market. Up to now, no data about its mass spectral fragmentation pattern, metabolism, and thus suitable targets for toxicological urine screenings have been available. Therefore, the aim of this study was to elucidate the metabolic fate of 7’N‐5F‐ADB in rat, human, and pooled human S9 (pS9). The main human urinary excretion products, which can be used as targets for toxicological screening procedures, were identified by Orbitrap (OT)‐based liquid chromatography–high resolution‐tandem mass spectrometry (LC–HRMS/MS). In addition, possible differentiation of 7’N‐5F‐ADB and 5F‐ADB via LC–HRMS/MS was studied. Using the in vivo and in vitro models for metabolism studies, 36 metabolites were tentatively identified. 7’N‐5F‐ABD was extensively metabolized in rat and human with minor species differences observed. The unchanged parent compound could be found in human urine but metabolites were far more abundant. The most abundant ones were the hydrolyzed ester (M5), the hydrolyzed ester in combination with hydroxylation of the tertiary butyl part (M11), and the hydrolyzed ester in addition to glucuronidation (M30). Besides the parent compound, these metabolites should be used as targets for urine‐based toxicological screening procedures. Two urine‐paired human plasma samples contained mainly the parent compound (c = 205 μg/L, 157 μg/L) and, at a higher abundance, the compound after ester hydrolysis (M5). In pS9 incubations, the parent compound, M5, and M30 were detectable among others. Furthermore, a differentiation of both compounds was possible due to different retention times and fragmentation patterns.  相似文献   
6.
李源  高元平  罗昊  李爱暖  吕露阳  徐燕  严亨秀  曾锐 《中草药》2019,50(12):2856-2861
目的建立一种UPLC-Q-Orbitrap HRMS定量分析方法,同时测定秦艽炮制前后8种化学成分(龙胆苦苷、马钱苷酸、獐牙菜苦苷、獐牙菜苷、木犀草素、异牡荆素、芹菜素、山柰酚)含量的变化。方法采用Waters Acquity UPLC BEH C_(18)(100 mm×2.1 mm,1.7μm)色谱柱,以甲醇-0.1%甲酸水溶液为流动相进行梯度洗脱,体积流量0.3 mL/min,柱温35℃。质谱采用负离子检测模式进行检测。结果秦艽经清炒、酒炙后环烯醚萜类含量均明显升高,且清炒后龙胆苦苷和马钱苷酸含量具有统计学差异。黄酮类在清炒和酒炙后含量变化不大。2类成分总的含量变化为环烯醚萜类成分含量清炒酒炙生品;黄酮类成分含量生品酒炙清炒。结论建立的UPLC-Q-Orbitrap HRMS同时测定秦艽炮制前后8种成分的方法准确、稳定,为进一步研究秦艽炮制前后主要成分的变化奠定了基础。  相似文献   
7.
李宁 《中草药》2019,50(3):573-581
目的为更加全面、系统、快速地表征参桂胶囊有效化学成分谱,采用超高效液相色谱-四极杆/静电场轨道阱高分辨质谱(UHPLC-Q-OrbitrapHRMS)技术对参桂胶囊中主要化学成分进行快速识别和归属分类。方法采用ACQUITY UPLC?BEH C18色谱柱(100 mm×2.1 mm,1.7μm),以乙腈(A)-0.1%甲酸水(B)为流动相进行梯度洗脱,以实现化合物的前期分离;然后通过Q-Orbitrap MS正、负离子同时监测,一级全扫描及自动触发二级质谱扫描的模式捕捉未知成分的精确相对分子质量及碎片离子信息,同时与对照品的保留时间和质谱数据信息进行匹配,并结合相关文献以及Chemical Book、Mass Bank等数据库最终实现对中药中复杂成分的快速准确识别。结果本研究共鉴定出40种化学成分,其中包括16种皂苷类、6种有机酸类、13种内酯类及5种其他类。结论本法可快速、准确地识别参桂胶囊中主要化学成分,同时为其进一步的药效物质基础、质量控制及临床合理应用等研究奠定了科学的前期基础。  相似文献   
8.
目的:为系统阐明复方中药制剂妇可靖胶囊中的化学成分组成,采用超高效液相色谱-四级杆/静电场轨道阱高分辨质谱(UPLC-Q-Orbitrap HRMS),对妇可靖胶囊的化学成分进行鉴定分析。方法:通过UPLC-Q-Orbitrap MS扫描提供的化合物精确相对分子质量、多级碎片离子信息,同时与对照品的的相对保留时间和质谱数据比对,并结合相关参考文献或Mass Bank、Chemical Book等数据库信息从而实现对化合物的准确定性。结果:共鉴定出67种化学成分,其中主要包括酚酸类、醌类、苯酞内酯类、黄酮类、萜类及其苷类、脂肪酸类等化学成分。结论:所建立的方法可系统、准确、快速地鉴定妇可靖胶囊中的多种化学成分,并为其药效物质基础及质量控制等研究提供了科学的理论依据。  相似文献   
9.
Atypical myopathy (AM) is a fatal disease in horses presumably caused by hypoglycine A (HGA) from ingested maple seeds and its active metabolite methylene cyclopropyl acetic acid (MCPA). The aim of this study was the development and validation of a rapid and simple assay for HGA and MCPA‐carnitine in horse serum and its application to authentic samples. Identification and quantification were carried out by ultra high performance liquid chromatography–high resolution tandem mass spectrometry (UHPLC–HRMS/MS) with full‐scan/data‐dependent MS/MS. Chromatographic separation was performed by isocratic elution on a hydrophilic interaction liquid chromatography (HILIC) column (100 x 2.1 mm, 1.7 μm). Serum samples (250 μL) were worked up by protein precipitation. The method was validated according to international guidelines with respect to selectivity, linearity, accuracy, precision, matrix effects, and recovery. The calibration range was from 100 to 2000 ng/mL for HGA and from 10 to 1000 ng/mL for MCPA‐carnitine. HGA and MCPA‐carnitine showed acceptable accuracy and precision (bias ‐3.0% to 1.1%; RSD 9.2% to 12.4%). The limit of quantification (LOQ) was defined as the lowest calibrator and well below the lowest published serum concentrations in affected horses. Matrix effects ranged from ‐79% to +20% (RSD 4.2% to 14.4%), recoveries from 17.9% to 21.1% (RSD 2.3% to 10.8 %) for low and high quality control samples, respectively. Applicability was tested in 10 authentic AM cases. In all specimens, relevant amounts of HGA and MCPA‐carnitine were found (570–2000 ng/mL; ~8.5–150 ng/mL, respectively). The developed assay allows reliable identification and quantification of HGA and MCPA‐carnitine in horse serum and will be helpful to further study the association between HGA/MCPA and AM.  相似文献   
10.
目的 应用超高效液相色谱-四级杆/静电场轨道阱高分辨质谱(UHPLC-Q-Orbitrap HRMS)对丹灯通脑胶囊中的化学成分进行快速分析鉴别。方法 采用ACQUITY UPLC® BEH C18色谱柱(2.1 mm×50 mm,1.7 μm),乙腈-0.1%甲酸水为流动相进行梯度洗脱,分离各个化学成分,质谱采用全扫描模式,正负离子同时扫描检测色谱流出物。根据质谱提供的化合物精准分子量、多级碎片离子信息,结合相关参考文献和数据库信息,同时与对照品的相对保留时间和质谱数据进行比对,定性鉴定化合物。结果 共鉴定出59种化学成分,主要包括黄酮类、醌类、有机酸类等化学成分,并对其药材来源进行了归属。结论 利用UHPLC-Q-Orbitrap HRMS建立的鉴别方法,能够准确、系统、快速地鉴定丹灯通脑胶囊中的多种化学成分,为研究丹灯通脑胶囊药效物质基础及其质量标准提供依据和参考。  相似文献   
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