JOURNAL OF CHROMATOGRAPHY A
·
2016
·
IF 3.926
Xiao-Fei Gu,Yue Zhao,Kan Li,Meng-Xiang Su,Fang Yan,Bo Li,Ying-Xiang Du,Bin Di
Structure elucidation of volatile aromatic isomers at trace level has long been considered as an elusive task, due to their structural similarities and similar polarities, even with the aid of many spectroscopic techniques such as mass spectrometry and nuclear magnetic resonance (NMR) spectroscopy. Single-crystal X-ray diffraction (SCD) is recognized as one of the most powerful structural elucidation techniques. The recently developed crystalline sponge method overcomes the intrinsic limitation of SCD that the target molecules must be single crystals, being able to analyze non-crystalline and trace-amount compounds without any special treatment. In order to investigate whether the crystalline sponge method could be used for the structure elucidation of closely related isomers or other volatile and even oily compounds in complex mixtures at trace level, we combined HPLC separation with the crystalline sponge method for X-ray crystallographic analysis. In this paper, two pairs of volatile aromatic isomers including cis / trans isomers of asarone and positional isomers of carvacrol and thymol, as well as the main volatile component in essential oil extracted from Acorus Tatarinowii , were first isolated by HPLC and encapsulated into the crystalline sponge then elucidated by X-ray crystallographic analysis. Direct observation of these volatile compounds by X-ray crystallography was achieved using only microgram quantities without crystallization or derivatization. Unambiguous identification of these compounds was realized without reference standards. This strategy offers a promising platform capable of providing high-confidence detailed structural information of closely related isomers as well as other volatile and even oily compounds in complex mixtures in microgram quantities.
研究领域:
分析化学
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晶体学
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药学
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DOI
PubMed
高影响因子
Chinese Journal of Natural Medicines
·
2019
·
IF 1.773
Da LI,Jian-Qi XIAO,Wen-Yuan LIU,Chao-Feng ZHANG,Toshihiro AKIHISA,Masahiko ABE,Eliot-T. MASTERS,Wei-Wei ZHAI,Feng FENG,Jie ZHANG
The aim of the study was to determine the feasibility of the Vitellaria paradoxa nutshell as a new medicinal resource for treating diabetes. A total of forty-one compounds were identified by HPLC-DAD-Q-TOF-MS and phytochemical methods in V. paradoxa nutshell methanol extract. Based on HPLC fingerprints, four characteristic constituents were quantified and the origin of twenty-eight V. paradoxa nutshells from seven sub-Saharan countries was compared, which were classified into three groups with chemometric method. Twenty-eight samples contained high total phenolic content, and exhibited moderate-higher antioxidant activity and strong α -glucosidase inhibitory activity. Furthermore, all fractions and isolated compounds were evaluated for their antioxidant and α -glucosidase inhibitory activities, and α -glucosidase inhibitory action mechanism of four characteristic constituents including protocatechuic acid, 3, 5, 7-trihydroxycoumarin, (2 R , 3 R )-(+)-taxifolin and quercetin was investigated via molecular docking method, which were all stabilized by hydrogen bonds with α -glucosidase. The study provided an effective approach to waste utilization of V. paradoxa nutshell, which would help to resolve waste environmental pollution and provide a basis for developing potential herbal resource for treating diabetes.
研究领域:
药理学
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药物化学
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植物科学
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环境科学
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DOI
PubMed
高影响因子
TALANTA
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2019
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IF 4.916
Qiaohong Peng,Yue Wu,Hailin Cong,Youqing Shen,Khalid Mahmood,Bing Yu
In recent decades, ionic liquid-modified packing materials as stationary phases of high performance liquid chromatography (HPLC) have attracted widespread attention due to their comprehensive properties. In this work, monodisperse porous polymeric ionic liquid microspheres were directly prepared using a seeded emulsion polymerization method and applied as stationary phase of HPLC. The effects of porogen , monomer and crosslinker on the properties of porous P(IL-DVB) microspheres were investigated in detail. Porous P(IL-DVB) microspheres with good stability, monodispersity and relatively high specific surface area were selected as stationary phase to successfully separate benzene and its homologues, and nucleosides and alkaloids under reversed phase chromatography (RPLC) mode and hydrophilic interaction chromatography (HILIC) mode, respectively.
研究领域:
分析化学
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材料科学
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色谱学
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DOI
高影响因子
JOURNAL OF CHROMATOGRAPHY B-ANALYTICAL TECHNOLOGIES IN THE BIOMEDICAL AND LIFE SCIENCES
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2014
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IF 2.694
Yunfang Li,Yu Chen,Chuying Xiao,Dan Chen,Yuxiu Xiao,Zhinan Mei
α-Amylase inhibitors play an important role in management of diabetes and obesity. In order to rapidly discover potent α-amylase inhibitors from medicinal plants, a ligands-screening method based on enzyme-immobilized magnetic nanoparticles integrated with HPLC was developed. Amine-terminated magnetic nanoparticles were prepared for the immobilization of α-amylase. Based on the affinity theory, the α-amylase-coated magnetic nanoparticles were employed to fish out the ligands from the extracts of Garcinia xanthochymus , and the elutes were examined by HPLC. As a result, three ligands were screened out. Isolation and identification were carried out subsequently. By analyzing the UV, MS and NMR spectra, they were identified as three biflavonoids including GB2a glucoside (2), GB2a (3) and fukugetin (4). The IC 50 values of the three compounds were also determined. The results suggest the proposed approach is efficient and accurate, and has great potential in rapid discovery of drug candidates from medical plants.
研究领域:
药理学
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生物化学
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药物发现
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DOI
PubMed
高影响因子
JOURNAL OF CHROMATOGRAPHY B-ANALYTICAL TECHNOLOGIES IN THE BIOMEDICAL AND LIFE SCIENCES
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2019
·
IF 2.813
Zheng-ming Qian,Ling Chen,Meng-qi Wu,De-qiang Li
Rapid discovery of active ingredients from complex matrices is one of great challenges for modern drug development. Traditional methods often require many sample treatment steps, including an extraction step with exclusively dedicated solvents followed by repeated separation and activities assessment. This present work described an integrated analytical setup for natural antioxidants discovery in which the online extraction (OLE) of a solid sample is directly coupled to its analysis by high performance liquid chromatography-diode array detector-quadrupole time-of-flight tandem mass spectrometry and 2,2′-Azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS) antioxidant assay (OLE-HPLC-DAD-QTOF-MS/MS-ABTS). This developed approach makes sample extraction, chromatographic separation and chemical detection, and antioxidant assay integrated into a single HPLC injection and was successfully applied for the rapid discovery of natural antioxidant bioactives from Polygonum viviparum . A total of 21 secondary metabolites were characterized according to their retention times, ultraviolet (UV) spectra, exact mass and fragmentation ions in MS/MS spectra, and 18 of them displayed antioxidant activity (response as negative peaks in antioxidant assay). This work describes a simple, green and efficient approach to minimize the sample consumption (only 0.4 mg was required) and eliminate complex sample treatment procedures. The developed OLE-HPLC-DAD-QTOF-MS/MS-ABTS system offers new perspectives for rapid chemical profiling of natural products and their antioxidants discovery.
研究领域:
分析化学
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植物化学
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药物发现
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DOI
PubMed
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2025
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IF 4
Qianyu Wu,Yu Zhang,Ce Sun,Jun Dang
In this study, we developed an online HPLC-lipoprotein lipase system capable of directly recognizing chromatographic peaks corresponding to lipoprotein lipase affinity agents from Nitraria tangutorum . Notably, using the HPLC-lipoprotein lipase system, six lipoprotein lipase affinity agents were successfully recognized and isolated with purities > 95 %, including one phenylpropanoid, one apigenin, and four quercetin derivatives. In vitro enzymatic assays and molecular docking studies demonstrated that these glycosylated compounds bind effectively to the active site of lipoprotein lipase, with binding energies ranging from -7.2 to -8.8 kcal/mol. The compounds also showed notable affinity, with median inhibitory concentration values between 56.2 μM and 202.3 μM and half-maximal effective concentration values ranging from 106.8 μM to 311.0 μM. These results suggest that quercetin glycosides in Nitraria tangutorum contribute significantly to the regulation of lipoprotein lipase activity. Importantly, the established online HPLC-lipoprotein lipase recognition system demonstrated broad application prospects, particularly by providing a rapid and high-precision method for discovering lipoprotein lipase affinity agents in chemically complex natural products.
研究领域:
天然产物化学
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药物分析学
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分子药理学
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生物色谱技术
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酶抑制剂研究
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DOI
PubMed
高影响因子
FOOD CHEMISTRY
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2019
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IF 5.399
Yun-Jiao Ma,An-Qi Bi,Xiao-Yuan Wang,Lei Qin,Ming Du,Liang Dong,Xian-Bing Xu
The dispersion solid-phase microextraction (DSPE) combined with dispersion liquid–liquid microextraction (DLLME) was developed as a rapid, simple and effective pretreatment method for the determination of flavor enhancers (maltol, ethyl maltol, vanillin, methyl vanillin, ethyl vanillin) of ready-to-eat seafood products (dried squid, baked squid, fried fish, steamed abalone). Under the optimized DSPE–DLLME method, the developed method exhibited low limits of quantitation (0.20–0.50 μg g −1 ) and excellent linearity (R 2 ≥ 0.995). The recoveries of flavor enhancers in the actual samples were 83.7%–114.9%. Compared with traditional pretreatment methods, the developed DSPE–DLLME method was rapid (17 min) and easy to determine the flavor enhancers by high performance liquid chromatography with photodiode array detector (HPLC-PDA). In the actual samples, creamy compounds such as vanillin, methyl vanillin and ethyl vanillin were hardly found. However, the flavor compounds produced by thermal reactions such as maltol (except for dried squid 3) and ethyl maltol were present in all samples.
研究领域:
食品科学
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分析化学
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色谱学
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DOI
PubMed
高影响因子
Analytical Methods
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2018
·Vol. 10
·期 11
·1325-1330
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IF 2.073
Yong Zhang,Zhizhong Zou,Guixing Chou
To quickly determine the amounts of kirenol, darutoside and darutigenol in Herba Siegesbeckiae using HPLC, the efficiency of sample cleanup with different solid phase extraction methods was systematically investigated. The results showed that a polymer based strong anion exchange (P-SAX, 200 mg/6 mL) sorbent could separate and enrich diterpenoids providing rapid determination without impurity interference. In this paper a new HPLC-UV method using a core–shell column (Boltimate C18 3.0 × 100 mm, 2.7 μm) for the quantitative determination of three diterpenoids was developed. Under optimum experimental conditions, P-SAX pretreatment with a core–shell analytical column exhibited satisfactory results in the determination of diterpenoids in Herba Siegesbeckiae with recovery rates of 95–102%, relative standard deviations below 1.1%, a limit of quantitation as low as 0.1 6 μg mL−1, and a short analytical runtime of 8 min. Finally, the proposed method was successfully applied in the profiling of diterpenoids in Herba Siegesbeckiae from different regions.
研究领域:
分析化学
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生药学
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植物科学
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DOI
高影响因子
JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS
·
2020
·
IF 3.209
Youxi Jin,Yu Pan,Biao Jin,Dongri Jin,Chunbo Zhang
(S)-1-(5-(4-Methylpiperazin-1-yl)-2,4-dinitrophenyl)pyrrolidine-2-carboxylic acid (Pro-PPZ) was employed as a chiral derivatization reagent (CDR) for the efficient enantioseparation and ultrasensitive mass spectrometric detection of chiral amines. Pro-PPZ was prepared from the one-step reaction of 1-(5-fluoro-2,4-dinitrophenyl)-4-methylpiperazine (PPZ) and l -proline. Two amines and two amino acid methyl esters were selected as model chiral amines, which were easily labeled with Pro-PPZ under mild reaction conditions (35 °C for 10 min) generating Pro-PPZ-amine derivatives. The resulting diastereomers were completely separated by reversed-phase liquid chromatography (RP-LC) using an ODS column ( R s = 3.4–17.0 for amines). Ultrasensitive detection limits on femtomolar level were obtained for the tested amines using multiple reaction monitoring (MRM) chromatograms at a single monitoring ion, m/z 289 (0.1–5.0 fmol for amines). The practical metabolite analysis of (R)-1-aminoindan (R-AI) in saliva samples was performed by LC–MS/MS using the Pro-PPZ derivatization method. The method was validated in terms of precision, accuracy, and linearity. Using this method, R-AI concentrations in saliva were determined after a single oral administration of the drug rasagiline to healthy male and female subjects, but no (S)-1-aminoindan (S-AI) was detected, which suggesting that R-AI was not converted into S-enantiomer in the metabolic process. R-AI concentrations in four healthy volunteers ranged from 32.85 nM to 49.45 nM, with an average value of 43.76 nM. To date, there is no LC–MS (or MS/MS) method reported for the enantioselective determination of R-AI in human saliva samples.
研究领域:
分析化学
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药物代谢
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临床医学
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DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2024
·
IF 4.9
Xiao-Kang Fu,Si-Qi Han,Xiao-Bo Zhao,Jing-Yan Kang,Wei Ha,Yan-Ping Shi
Steroid hormone residues in food are a significant sources of endocrine disrupting chemicals (EDCs) that can adversely affect public health. However, the current analytical methods for determining steroid hormones using liquid chromatography-tandem mass spectrometry (LC-MS/MS) can be challenging due to the poor ionization efficiency of steroid hormones and the matrix effect of complex food samples. Herein, based on Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC) reaction and stable isotope labeling (SIL) technique, a novel pair of chemoselective probes ABI / d 5 -ABI was precisely designed and synthesized. This pair of probes comprises a H/D isotope tag, a linker, a reactive site azido group (N 3 ) and a MS tag (imidazolium salt). The probe ABI was employed to label ethynyl-containing steroid hormones in real samples and d 5 -ABI was applied to label standards, respectively, followed by mixing the two labeled samples for high performance (HP)LC-MS/MS analysis. It was found that the ionization efficiencies of target analytes were increased by 17–4532 folds after ABI labeling. More importantly, the heavy labeled samples serving as internal standards (ISs) can effectively compensate matrix effect during HPLC-MS/MS analysis. Finally, the proposed SIL-HPLC-MS/MS method was successfully used to highly sensitive determine four synthetic steroid hormones in food samples (milk, pork and egg). Furthermore, the good detection limits (0.015–0.020 ng/mL), satisfactory recoveries (75.7–122.9 %), and precisions (RSDs less than 9.2 %) were obtained. Hence, the established method not only provides new insights in designing SIL probes for determination of ethynyl-containing analytes within complex matrix, but also extends the application of CuAAC reaction in the field of food chemistry.
研究领域:
分析化学
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食品科学
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质谱技术
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DOI
高影响因子
RSC Advances
·
2018
·Vol. 8
·期 68
·38715-38720
·
IF 2.936
Yin Qian,Xi Chen,Jin Qi,Xuming Liu
Protein tyrosine nitration plays a key role in many inflammatory and cardiovascular diseases and diabetes. Many natural products are used to treat these diseases through their ability to potentially interfere this reaction. Here, we describe a novel method to provide active fingerprinting of inhibition of tyrosine nitration by natural products based on post-column tyrosine nitration reaction analysis using high-performance liquid chromatography coupled to a photometric diode array. Results indicated that lotus leaf extracts exhibited obvious inhibitory activity against tyrosine nitration by peroxynitrite, and that chemical and active fingerprints were simultaneously established, with the active fingerprints indicating the active compounds of the lotus leaves. Additionally, flavonoids were screened as the principal active compounds involved in inhibiting tyrosine nitration in the lotus leaf extracts, with quercetin-3-O-glucuronide and quercetin-3-O-glucoside exhibiting the greatest contributions. Moreover, our results suggested that lotus leaves from three regions (Nanjing, Suzhou, and Hangzhou) exhibited the best inhibitory activity. These findings indicated the usefulness of this method for screening active compounds involved in inhibiting protein tyrosine nitration, and that similar strategies can likely be applied to evaluate the inhibitory activity against tyrosine nitration of other natural products.
研究领域:
分析化学
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药理学
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天然产物
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生物化学
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DOI
PubMed
高影响因子
TALANTA
·
2019
·
IF 4.916
Xiaoyu Jia,Junyi Zhao,Hongyun Ren,Jiani Wang,Zixiao Hong,Xian Zhang
Zwitterion-functionalized polymer microspheres (ZPMs) have been designed and used as the core adsorbent for the selective and rapid enrichment of mercury species in environmental waters by an on-line solid-phase extraction (SPE). Zwitterionic S-ZPMs and N-ZPMs having an anionic sulfonic group, but differing in cationic S + and N + moieties were prepared from Merrifield resin by treating with 1,2-ethanedithiol and imidazole , followed by modification with 1,3-propanesultone. Without any additional reagents, inorganic mercury (In-Hg), methylmercury (MeHg) and ethylmercury (EtHg) were quantitatively adsorbed on the home-made mini-column packed with ZPMs. Following extraction with 60 mM ammonium acetate and 0.15% L -cysteine ( L -Cys) solution within seconds, separation and speciation of mercury were successfully achieved by the HPLC–ICP-MS technique. Under the optimized experimental conditions, the enrichment factors (EFs) are up to 105 and 98 for inorganic and organic mercury only with 40 mL sample solution, respectively. The low detection limits of 0.78 ng L −1 , 0.63 ng L −1 , and 0.49 ng L −1 were reached for In-Hg, MeHg and EtHg, respectively, with the relative standard deviations (RSDs) below 4.1%. The feasibility and accuracy of the on-line SPE–HPLC–ICP-MS method were successfully applied for mercury speciation in surface water, seawater as well as certified reference material (CRM). The results here demonstrate a facile, sensitive and selective method for speciation of mercury at trace levels.
研究领域:
分析化学
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环境科学
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化工工程
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DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）