Ultra-fast Liquid Chromatography-tandem Mass Research Articles

Determinants of gefitinib pharmacokinetics in healthy Chinese male subjects: A pharmacogenomic study of cytochrome p450 enzymes and transporters.

Gefitinib, an inhibitor of the epidermal growth factor receptor tyrosine kinase, exhibited a wide interindividual variability in pharmacokinetics. In the present study, we aimed to evaluate the impact of single-nucleotide polymorphisms in the metabolizing enzymes and transporters on gefitinib disposition in healthy Chinese subjects. Fourteen single-nucleotide polymorphisms, including polymorphisms of ATP-binding cassette (ABC) transporters and cytochrome P450 enzymes, were genotyped by Sanger sequencing, and the concentration of gefitinib was measured by ultrafast liquid chromatography-tandem mass spectrometry. The association between the pharmacokinetic parameters (peak plasma concentration [Cmax ], time to reach Cmax , plasma half-life, area under the concentration-time curve from 0 to 168hours [AUC(0-168h) ], AUC(0-∞) and plasma clearance [CL/F]) and genotypes was evaluated using unpaired t test or Mann-Whitney U test. A stepwise multiple linear regression analysis was applied to assess the relationships between multiple factors and gefitinib pharmacokinetics. Thirty-nine healthy Chinese male subjects were enrolled in the pharmacokinetic study. Subjects carrying an ABCG2 A allele (c.421CA+c.421AA genotypes) exhibited 33 and 37% increases in the mean gefitinib AUC(0-168h) and AUC(0-∞) values (P<.05), respectively, compared to that of subjects carrying wild-type ABCG2 (c.421CC). Additionally, the mean CL/F of the c.421A allele carriers was 32% less than that of the c.421CC carriers (P<.05). No associations were found between polymorphisms in other metabolic enzymes or ABC transporters and gefitinib pharmacokinetics. Our results suggested that a single-nucleotide polymorphism in ABCG2 (c.421C>A) significantly affected the pharmacokinetics of gefitinib. Further studies are required to evaluate the effects of single-nucleotide polymorphism on the pharmacokinetics, pharmacodynamics and toxicity of gefitinib.

Chemical composition of isoflavones compounds and antioxidants from Feijoa sellowiana leaves

Isoflavonic compounds and antioxidants from the leaves of Feijoa sellowiana Berg grown in Casablanca (Morocco) was analyzed by a sensitive and reliable ultra-fast liquid chromatography tandem mass spectrometry (UFLC-MS/MS) method. The identified compounds were rich in phenolics compounds, thus fifteen constituents were found.

Dynamic Variations in Multiple Bioactive Constituents under Salt Stress Provide Insight into Quality Formation of Licorice.

The demand for licorice and its natural product derivatives in domestic and foreign market is considerably huge. The core production areas of licorice are covered with salinity and drought land in northwestern China. Studies have shown that suitable environmental stress can promote the accumulation of glycyrrhizin and liquiritin to improve its quality as medicinal materials. However, there are few reports on other bioactive constituents of licorice, not to mention their dynamic accumulation under stressed conditions. To explore the quality formation of licorice from the perspective of salt influence, a reliable method based on ultra-fast liquid chromatography tandem triple quadrupole mass spectrometry (UFLC–MS/MS) was established for simultaneous determination of sixteen bioactive constituents, including triterpenoids, flavonoids, chalcones and their glycosides. Physiological experiments were performed to investigate salt tolerance of licorice under different salinity treatments. The expressions of crucial genes (bAS and CHS), key enzymes of triterpenoid and flavonoid synthesis, were also tested by qRT-PCR. Our study found that 50 mM NaCl treatment (low stress) was the most favorable to promote the accumulation of bioactive constituents in the long term, without harming the plants. Flavonoid accumulation of non-stressed and low-stressed groups became different in the initial synthesis stage, and glycosyltransferases may have great influence on their downstream synthesis. Furthermore, bAS and CHS also showed higher levels in low-stressed licorice at harvest time. This work provides valuable information on dynamic variations in multiple bioactive constituents in licorice treated by salt and insight into its quality formation under stressed conditions.

Quality evaluation of Lonicerae Japonicae Flos and Lonicerae Flos based on simultaneous determination of multiple bioactive constituents combined with multivariate statistical analysis.

IntroductionLonicerae Japonicae Flos (LJF) and Lonicerae Flos (LF) belong to different genera of Caprifoliaceae. They have been historically utilised as herbal medicine to treat various diseases. However, the comprehensive assessment of them still remains a challenge.ObjectiveTo develop a comprehensive method of ultra‐fast liquid chromatography‐tandem triple quadrupole mass spectrometry (UFLC‐QTRAP‐MS/MS) coupled with multivariate statistical analysis for the quality evaluation and reveal differential components of LJF and LF.MethodologyA validated UFLC‐QTRAP‐MS/MS method was established for simultaneous determination of 50 constituents, including 12 organic acids, 12 flavonoids, 6 iridoids, 3 saponins, 13 amino acids and 4 nucleosides. The obtained data were employed to multivariate statistical analysis. Principal component anlysis (PCA) and partial least squares determinant analysis (PLS‐DA) were performed to classify and reveal differential components of samples; grey relational analysis (GRA) was introduced to assess the samples according to the contents of 50 constituents by calculating the relative correlation degree of each sample.ResultsFifty constituents were simultaneously determined of LJF and LF. Based on obtained data, PCA and PLS‐DA were easy to distinguish samples and the classification of the samples was related to 11 chemical constituents. GRA implied the quality of LJF was better, and that the flower buds were superior to the flowers. Moreover, organic acids are the main components of samples.ConclusionThis study not only established a method of simultaneous determination of multiple bioactive constituents in LJF and LF, but provided comprehensive information on the quality control of them. The developed method is conducive to distinguish orthologues or paralogues of them, and supply the support for “heterologous effects”.

Evaluating the treatment effectiveness of copper-based algaecides on toxic algae Microcystis aeruginosa using single cell-inductively coupled plasma-mass spectrometry

Single cell-inductively coupled plasma-mass spectrometry (SC-ICP-MS) is an emerging technology. In this work, we have developed a novel SC-ICP-MS method to quantify metal ions in individual cells of a toxic cyanobacterial species, Microcystis aeruginosa (M. aeruginosa), without complicated post-dosing sample preparation, and applied this method to study the treatment effectiveness of copper-based algaecides (cupric sulfate and EarthTec®) on the toxic algae M. aeruginosa. The developed SC-ICP-MS method uses new intrinsic metal element magnesium to determine real transport efficiency and cell concentration. The cell viability and microcystin-LR release by algaecide treatment were studied by flow cytometry and ultra-fast liquid chromatography-tandem mass spectrometry, respectively. The results showed that this novel method was very rapid, highly sensitive (detection limits of intracellular copper and magnesium were 65 ag/cell and 98 ag/cell, respectively), and reproducible (relative standard deviation within 12%). The algaecide effectiveness study further demonstrated that copper in the forms of cupric sulfate and copper-based algaecide EarthTec® successfully diminished M. aeruginosa populations. The higher the copper concentration used to treat the cells, the faster the speeds of copper uptake and cell lysis in the copper concentrations ranged from 0 to 200 μg/L of copper-based algaecide. The cells exhibit obvious heterogeneity in copper uptake. The result suggests that M. aeruginosa cells uptake and cumulate copper followed by cellular lysis and microcystin-LR release. These novel results indicated that though the copper-based algaecides could control this type of harmful algal bloom, further treatment to remove the released algal toxin from the treated water would be needed.Graphical abstract

Comparison of Multiple Bioactive Constituents in the Flower and the Caulis of Lonicera japonica Based on UFLC-QTRAP-MS/MS Combined with Multivariate Statistical Analysis

Lonicerae japonicae flos (LJF) and Lonicerae japonicae caulis (LJC) are derived from different parts of Lonicera japonica Thunb. (Caprifoliaceae), and have been used as herbal remedies to treat various diseases for thousands of years with confirmed curative effects. However, little attention has been paid to illustrating the differences in efficacy from the perspective of phytochemistry. In the present study, a simultaneous determination of 47 bioactive constituents, including 12 organic acids, 12 flavonoids, six iridoids, 13 amino acids and four nucleosides in 44 batches of LJF and LJC samples from different habitats and commercial herbs was established based on ultra-fast liquid chromatography tandem triple quadrupole mass spectrometry (UFLC-QTRAP-MS/MS). Moreover, principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA) and t-test were then performed to classify and reveal the differential compositions of LJF and LJC according to the content of the tested constituents. The results demonstrated that the types and contents of chemical components (e.g., isochlorogenic acid A, chlorogenic acid, neochlorogenic acid, quinic acid, secologanic acid, luteoloside, loganin, secoxyloganin, morroniside and L-isoleucine) were significantly different, which may lead to the classification and the differences in efficacy of LJF and LJC. Our findings not only provide a basis for the comprehensive evaluation and intrinsic quality control of LJF and LJC, but also pave the way for discovering the material basis contributing to the different properties and efficacies of the two medicinal materials at the phytochemical level.

Simultaneous determination of 19 mycotoxins in lotus seed using a multimycotoxin UFLC-MS/MS method.

In relevance to the internal components and improper environmental conditions, lotus seeds are susceptible to fungal contamination and mycotoxins residue, leading to harmful impacts on the quality and safety, as well as their pharmaceutical efficacy and clinical use. It is necessary and urgent to assess various mycotoxins residue in lotus seeds. This study aimed to develop a sensitive method for accurate assessment of multimycotoxin residues in lotus seeds. A simple and reliable modified ultrasonication-assisted extraction, QuEChERS purification based ultrafast liquid chromatography tandem mass spectrometry (UFLC-MS/MS) method was successfully developed for ultrasensitive determination of 19 multiclass mycotoxins in starch-rich lotus seeds. Four extraction modes and three clean-up sorbents for improving the recoveries of mycotoxins were optimized. Limits of detection (LODs) and quantification, linearity, precision, accuracy, and matrix effect were studied for method validation. For simultaneous qualitation and quantification, the 19 chemically diversified mycotoxins were well separated on a CAPCELL CORE C18 column (100mm×2.1mm, 2.7μm) and detected in positive/negative electrospray ionization mode within 7min. The validated method exhibited satisfactory linearity (r>0.995), ultragood selectivity (LODs of 0.1-15.0μg/kg), excellent precision (RSDs <13.0%) and convincing accuracy (recoveries between 79.4% and 131.6% with RSDs <14.4%). Matrix effect, between 54.5% and 113.6%, appeared especially for aflatoxins B1 and B2 , deoxynivalenol and T-2 toxins. Matrix-matched curve-based quantification showed that 26 (57.8%) out of 45 lotus seed samples were contaminated with one or more mycotoxins, and ochratoxin A, aflatoxin B2 , aflatoxin B1 and citrinin were the most prevalent mycotoxins. This study reports for the first time the incidence of a wide range of 19 mycotoxins in lotus seeds and the proposed method will get broad application for more trace components in other complex matrices.

Pharmacokinetic Study of Main Active Components of Rumex nepalensis Spreng Extract in Rats Plasma by UPLC-MS/MS

Background: The Rumex nepalensis Spreng (RNS) is a traditional Chinese medicine containing rich anthraquinones. However, through proper investigation we have found that there were no reports on the pharmacokinetics of RNS extract in rats. &lt;/P&gt;&lt;P&gt; Objective: We study on the pharmacokinetic behaviors of emodin, chrysophanol and physcion after oral administration of RNS extract in rat to achieve a better understanding of further clinical application and conduct the preparation development of the herb. Methods: In the present study, a sensitive and rapid ultra-fast liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method was developed and validated to determine the three anthraquinones such as chrysophanol, emodin and physcion in rat plasma along with danthron as the internal standard (IS). The analytes and IS were separated on an Acquity UPLC HSS T3 column (100 mm × 2.1 mm, 1.8 µm) by using the mobile phase of water with 3 mM ammonium acetate and acetonitrile as gradient elution at a flow rate of 0.4 mL min -1. The detection was performed on a triple quadrupole tandem mass spectrometer equipped with electrospray ionization (ESI) by multiple reactions monitoring (MRM) of the transitions at m/z 253.1 → 225.0 for chrysophanol, 269.0 → 224.9 for emodin, 282.7→ 240.0 for physcion and m/z 239.0 → 211.0 for IS. The limit of detection and lower limit of quantification were both 2 ng mL -1 in rat plasma. Results: Good linearity of this method was obtained in the range of 2-1000 ng mL -1 , and the correlation coefficient was greater than 0.990. According to regulatory guidelines, the established method was fully validated, and the results were within acceptable limits. Conclusion: The validated method was successfully applied into a pharmacokinetic study of orally administered RNS extract in rats.

Distribution of perfluorinated alkyl substances in marine shellfish along the Chinese Bohai Sea coast

Perfluorinated alkyl substances (PFASs) are emerging persistent organic pollutants, which pose a threat to human health primarily by dietary exposure, especially through seafood. Bohai Sea (a semi-closed sea located north of China) is an important shellfish aquaculture area that is possibly highly-polluted with PFASs. In this study, we first evaluated contamination by PFASs in a total of 230 samples of marine shellfish from the Bohai Sea. Samples included five important shellfish species, collected from important aquaculture spots distributed around the Bohai Sea. Samples were analyzed by an ultra-fast liquid chromatography-tandem mass spectrometry method, which could simultaneously detect 23 PFASs in shellfish. Our research verified that PFASs have become a threat to the safety of shellfish products in this area. Furthermore, contamination by PFASs in shellfish changed depending on the components of PFASs, the species of shellfish, and the sampling sites. Many of the 23 target compounds contributed to the high detection ratio (>50%) as follows: perfluorooctanoic acid (PFOA) > perfluorononanoic acid > perfluorodecanesulfonic acid > perfluorooctanesulfonic acid (PFOS). Compared with other dominant components, PFOA not only had the highest detection percentage in shellfish samples (98.3%), but its detection level contributed to 87.2% of total PFASs concentrations, indicating that PFOA is the major threat to the safety of shellfish products. The highest level of PFAS was found in clams (62.5 ng g−1 wet weight of PFOA). The concentration of total PFAS in different shellfish species showed the following trend: clams > mussels > scallops > whelks > oysters. The maximum concentration of total PFAS or PFOA was found in Shouguang. The total concentration of PFOS and its precursor were highest in Cangzhou, possibly due to local industrial activities. The results presented in this paper provide new data on the contamination of marine shellfish along the Bohai Sea coasts in China, and constitute a reference for future monitoring of contamination by emerging contaminants in Bohai coast.

A simple sensitive UFLC-MS/MS method for the simultaneous quantification of artesunate, dihydroartemisinin and quercetin in rat plasma and its application to pharmacokinetic studies.

An ultrafast liquid chromatography-tandem mass spectrometry (UFLC-MS/MS) method was developed for the simultaneous estimation of artesunate (ART), dihydroartemisinin (DHA, an active metabolite of ART) and quercetin (QRT) in rat plasma. The separation was achieved using a Zorbax C18 column (3 μm, 50 mm × 4.6 mm) as a stationary phase with a mobile phase of 0.1% formic acid (10% by volume) and methanol (90% by volume) at a flow rate of 0.4 mL min−1 and an injection volume of 10 μL. Artemisinin (ATM) was used as the internal standard (IS). Mass detection was performed by electrospray ionization (ESI)-tandem mass spectrometry via multiple reaction monitoring (MRM) in positive mode except for QRT, where negative ionization was used. The extraction recoveries of ART, DHA, and QRT from plasma were found to be 91.05–99.62%, 95.12–98.56% and 89.35–98.90%, respectively. The developed method was validated and successfully applied to the quantitative analysis of ART, DHA and QRT in plasma samples after the oral administration of ART and ART–QRT pure drugs to rats at the dose of 5 mg kg−1 each. The results reveal that the developed method can be further used for the quantification of the proposed combination drugs in nanoformulations.

Variations in Physiology and Multiple Bioactive Constituents under Salt Stress Provide Insight into the Quality Evaluation of Apocyni Veneti Folium.

As one of the major abiotic stresses, salinity stress may affect the physiology and biochemical components of Apocynum venetum L. To systematically evaluate the quality of Apocyni Veneti Folium (AVF) from the perspective of physiological and the wide variety of bioactive components response to various concentrations of salt stress, this experiment was arranged on the basis of ultra-fast liquid chromatography tandem triple quadrupole mass spectrometry (UFLC-QTRAP-MS/MS) technology and multivariate statistical analysis. Physiological characteristics of photosynthetic pigments, osmotic homeostasis, lipid peroxidation product, and antioxidative enzymes were introduced to investigate the salt tolerance mechanism of AVF under salinity treatments of four concentrations (0, 100, 200, and 300 mM NaCl, respectively). Furthermore, a total of 43 bioactive constituents, including 14 amino acids, nine nucleosides, six organic acids, and 14 flavonoids were quantified in AVF under salt stress. In addition, multivariate statistical analysis, including hierarchical clustering analysis, principal component analysis (PCA), and gray relational analysis (GRA) was employed to systematically cluster, distinguish, and evaluate the samples, respectively. Compared with the control, the results demonstrated that 200 mM and 100 mM salt stress contributed to maintain high quality of photosynthesis, osmotic balance, antioxidant enzyme activity, and the accumulation of metabolites, except for total organic acids, and the quality of AVF obtained by these two groups was better than others; however, under severe stress, the accumulation of the oxidative damage and the reduction of metabolite caused by inefficiently scavenging reactive oxygen species (ROS) lead to lower quality. In summary, the proposed method may provide integrated information for the quality evaluation of AVF and other salt-tolerant Chinese medicines.

A unified approach for high-throughput quantitative analysis of the residues of multi-class veterinary drugs and pesticides in bovine milk using LC-MS/MS and GC–MS/MS

This paper reports a unified sample preparation approach for high-throughput multi-residue analysis of veterinary drugs and pesticides in a single sub-sample of bovine milk. The sample (5 g) was deproteinized with acetonitrile before an aliquot (I) was withdrawn, and the remainder was phase-separated using MgSO4 and NaCl. The acetonitrile layer (II) was recovered and the extracts combined, cleaned, and solvent-exchanged before the concentrations of veterinary drugs and pesticides were measured by ultra-fast liquid chromatography tandem mass spectrometry (UFLC-MS/MS). As a unique approach, extract II was analyzed simultaneously using gas chromatography tandem mass spectrometry (GC–MS/MS). Method performance for 78 drugs and 238 pesticides complied with CD 2002/657/EC and SANTE/11813/2017 guidelines, respectively, with significant savings in time and cost. Thus, it would be ideal for regulatory analysis of analytes ranging from non-polar organochlorine pesticides to polar drugs, including penicillins, quinolones, and tetracyclines.

Analysis of monofluoroacetic acid in human plasma by UFLC–MS/MS and its application in patients with sodium monofluoroacetate or monofluoroacetamide poisoning

Monofluoroacetic acid (FAcOH), was once widely used in baits as a rodenticide in agriculture. For intentional and unintentional misuses, the incidence of FAcOH poisoning has increased in recent years. Organic fluorine rodenticides such as sodium monofluoroacetate and monofluoroacetamide, the analogs of FAcOH, can easily be converted to FAcOH in vivo and cause injury. It is urgent to establish a simple and sensitive analytical method of FAcOH in human plasma and applied to clinical poison analysis. In this paper, an ultra-fast liquid chromatography-tandem mass spectrometry (UFLC–MS/MS) method was developed for determination of FAcOH in patient plasma. We used isotopic labelled FAcOH-13C2, D2 as the internal standard (IS). Plasma samples were simply precipitated with acetonitrile and the supernatant was injected directly for analysis. The chromatographic column was Phenomenex Luna® Silica column (100 × 2 mm, 3 μm), FAcOH was eluted by isocratic elution with a mobile phase of acetonitrile-water contains 5 mM ammonium formate with 0.2% formic acid. The retention time of FAcOH was 2.31 min A good linear response was from 0.25 to 200 μg/mL, with a correlation coefficient of r = 0.9980. The limit of detection was 0.05 μg/mL. The recoveries at three spiking levers were 89.51–93.03% with relative standard deviations ranged between 2.55–3.61%. This new method has been successfully applied to monitor 31 cases of patients suspected with sodium monofluoroacetate or monofluoroacetamide poisoning.

Measurement of pharmacokinetics and tissue distribution of three bioactive constituents from Zanthoxylum armatum DC in rat plasma and tissues through UFLC-MS/MS

The compounds of N-Methylanhydrotetrahydroberberrubine A, dictamnine and eudesmin were the primary bioactive components in the roots of Zanthoxylum armatum DC (Z. armatum). To clarify the pharmacokinetics and distribution of these three compounds, an ultra-fast liquid chromatography-tandem mass spectrometry (UFLC-MS/MS) was employed to determine the contents of these three compounds in rat plasma and seven tissues. The separation was achieved on a Kinetex XB–C18 100A column (2.1 × 50 mm, 2.6 μm, Phenomenex). The optimized mobile phase system was set with 0.1‰ formic acid aqueous solution (A) and acetonitrile (containing 0.1‰ formic acid) (B) with a programmed elution of 0.00 to 0.50 min, 2% B; 0.51–4.00 min, 30%–60% B; and 4.01–5.00 min, 2% B. All analytes were measured with optimized multiple reaction monitoring (MRM) in the positive ion ESI mode. Berberine hydrochloride was selected as the internal standard (IS). The MS/MS transitions of N-Methylanhydrotetrahydroberberrubine A, dictamnine, eudesmin and IS were 339.9135.1, 200.1 → 129.1, 387.4 → 369.0 and 337.1 → 321.1, respectively. The lower limits quantification (LLOQ) of the three analytes was 0.5–20 ng/ml. The linear ranges were 0.5–400 ng/ml for N-Methylanhydrotetrahydroberberrubine A and dictamnine and 20–4000 ng/ml for eudesmin. The present analysis showed that the two alkaloids were quickly absorbed, with Tmax in 0.167–0.292 h, and eudesmin was absorbed in 2.5 h. Moreover, all compounds were found at high concentrations in the gastrointestinal track. These results are helpful for further investigation of the clinical application of Z. armatum.

Subcritical water extraction of bioactive components from ginseng roots (Panax ginseng C.A. Mey)

The feasibility of applying subcritical water extraction (SWE), which is considered to be an environmentally friendly and efficient extraction technology for the extraction of bioactive components from ginseng roots, was evaluated by comparing it with conventional water (WE) and ethanol (EE) extraction methods SWE was conducted at different temperatures ranging from 120 to 200 °C, and WE and EE were performed by solid–liquid heating extraction methods using water or 70% (v/v) aqueous ethanol as a solvent, respectively. SWE showed significantly and markedly higher extraction yields of total sugar (TS), total protein (TPro), phenolic components (TP), and more potent antioxidant activities than WE and EE. The optimized temperature for TS, TP, and antioxidant activities was 200 °C, and that for TPro was 180 °C. Although vanillin–perchloric acid colorimetric quantification showed that SWE yielded more total ginsenosides (TG) than WE and EE, ultrafast liquid chromatography tandem mass spectroscopy (UFLC–MS/MS) analysis revealed that SWE induced extensive hydrolysis of the ginsenosides, except for Rg2. At 160 °C, SWE yielded 9.7- and 6.2-fold more Rg2 than WE and EE, respectively. In comparison, the extraction yields of R1, Rb1, Rb2, Rb3, Rc, Rd, Re, Rg1, and Ro decreased significantly with the increase of SWE temperature. These findings suggested that SWE is a promising environmentally friendly and efficient technology for extracting bioactive polysaccharides, proteins, TP, and Rg2 from ginseng roots, but it has potency to induce extensive hydrolysis of ginsenosides, such as Rb1 and Re.

Quality Evaluation of Apocyni Veneti Folium from Different Habitats and Commercial Herbs Based on Simultaneous Determination of Multiple Bioactive Constituents Combined with Multivariate Statistical Analysis.

Apocyni Veneti Folium (AVF) is a kind of staple traditional Chinese medicine with vast clinical consumption because of its positive effects. However, due to the habitats and adulterants, its quality is uneven. To control the quality of this medicinal herb, in this study, the quality of AVF was evaluated based on simultaneous determination of multiple bioactive constituents combined with multivariate statistical analysis. A reliable method based on ultra-fast liquid chromatography tandem triple quadrupole mass spectrometry (UFLC-QTRAP-MS/MS) was developed for the simultaneous determination of a total of 43 constituents, including 15 flavonoids, 6 organic acids, 13 amino acids, and 9 nucleosides in 41 Luobumaye samples from different habitats and commercial herbs. Furthermore, according to the contents of these 43 constituents, principal component analysis (PCA) was employed to classify and distinguish between AVF and its adulterants, leaves of Poacynum hendersonii (PHF), and gray relational analysis (GRA) was performed to evaluate the quality of the samples. The proposed method was successfully applied to the comprehensive quality evaluation of AVF, and all results demonstrated that the quality of AVF was higher than the PHF. This study will provide comprehensive information necessary for the quality control of AVF.

Agarwood Essential Oil Displays Sedative-Hypnotic Effects through the GABAergic System.

Although agarwood has been used as a tranquilizer in Asian countries for hundreds of years, the underlying pharmacological basis is still unclear. This study investigated the sedative-hypnotic effect of agarwood essential oil (AEO) using locomotor activity and pentobarbital-induced sleeping assays in mice. Single (1-day) and multiple (7- and 14-days) administrations of 60 mg/kg AEO generated significant sedative effect on inhibiting locomotor activity and hypnotic effect on pentobarbital-induced sleeping in mice. Interestingly, prolonged AEO treatment did not result in obvious desensitization. Concoitant measurement of the levels of brain neurotransmitters using ultrafast liquid chromatography-tandem mass spectrometry (UFLC-MS/MS) indicated that AEO had no significant effect on the levels of glutamic acid (Glu) and γ-aminobutyric acid (GABA) in the brain. However, the sedative-hypnotic effects were blocked by the type A GABA (GABAA) receptor antagonists bicuculline and flumazenil. In addition, AEO significantly elevated the expression of GABAA receptor subunits and subtypes in the cerebral cortex. Furthermore, AEO increased chlorine ion (Cl−) influx through GABAA receptors in human neuroblastoma cells. These results together demonstrate that AEO exerts its sedative-hypnotic effects through regulating gene expression of GABAA receptors and potentiating GABAA receptor function.

Simultaneous determination and tissue distribution studies of four phenolic acids in rat tissue by UFLC-MS/MS after intravenous administration of salvianolic acid for injection.

A rapid, simple and sensitive ultra-fast liquid chromatography tandem mass spectrometric method was developed and validated for simultaneous determination and tissue distribution studies of rosmarinic acid, salvianolic acid D, lithospermic acid and salvianolic acid B in rats after intravenous administration of salvianolic acid for injection. The tissue homogenate samples were pretreated by protein precipitation with pre-cooled acetonitrile. Chromatographic separation was achieved on a Waters Cortecs UPLC C18 column (1.6 μm, 2.1 × 100 mm) with a mobile phase composed of 0.1% formic acid-water and 0.1% formic acid-acetonitrile. Analytes were detected by electrospray ionization mass spectrometry and quantitated using multiple reaction monitoring. The method was fully validated. The calibration curves for the four phenolic acids were linear in the given concentration ranges. The precisions (relative standard deviation) in the measurement of quality control samples were <10% and the accuracies (relative error) were in the range of 0.28-11.22%. The reliable method was successfully applied to the tissue distribution studies of the four phenolic acids. The results showed that rosmarinic acid, salvianolic acid D, lithospermic acid and salvianolic acid B were rapidly distributed in tissues with the major amount found in kidney, and little crossed the blood-brain barrier. The developed method and the results provide a basis for further studies.

Integrated pharmacokinetics of ginsenosides after intravenous administration of YiQiFuMai powder injection in rats with chronic heart failure by UFLC-MS/MS.

YiQiFuMai powder injection (YQFM), derived from the classical traditional Chinese medicine (TCM) formula Shengmai San, is a modern preparation widely used to combat cardiovascular diseases, chronic heart failure (CHF) for example, in clinical practice in China. Ginsenosides are the major components of YQFM, which are responsible for its therapeutic effect. In this research, we developed a rapid, sensitive and simple method for simultaneous determination of ten ginsenosides from YQFM in CHF rat plasma with ultra-fast liquid chromatography tandem mass spectrometry (UFLC-MS/MS). After solid phase extraction (SPE), chromatography was done on an Acquity UPLC HSS T3 column (1.8μm, 100mm×2.1mm, i.d.) through an 8.0min gradient elution with acetonitrile and 0.1% formic acid in water, while mass spectrometry was performed in the positive ion electrospray ionization (ESI) mode. A good linearity was achieved for each analyte with correlation coefficient (r) >0.9920. The lower limits of quantification (LLOQ) were 1.25ng/mL for ginsenoside Rg1, Rd, Re and Rh1, 2.5ng/mL for ginsenoside Rf, Rg3, Rb2 and Rb3 and 5.0ng/mL for ginsenoside Rb1 and Rc, respectively. All the precision (RSD) data ranged from 1.7-14.5% and the accuracy (RE) data was within ±13.73%. Moreover, the validated method has been applied to investigate the integrated pharmacokinetic profiles of ginsenosides in CHF rats following intravenous administration of YQFM successfully.

Simultaneous determination of phenolic acids and diterpenoids and their comparative pharmacokinetic study in normal and acute blood stasis rats by UFLC–MS/MS after oral administration of Guan-Xin-Shu-Tong capsules

Guan-Xin-Shu-Tong capsules are one of the well-known and first-line Chinese traditional herbal formula for treating coronary heart disease. A validated and sensitive method via ultra fast liquid chromatography-tandem mass spectrometry (UFLC-MS/MS) was established to simultaneously determinate five phenolic acids and four diterpenoids in rats in order to investigate their pharmacokinetic profiles firstly. Analytes were extracted by ethyl acetate and determined via multiple reaction monitoring mode in both positive and negative ion modes. The values for limit of quantification were in range of 0.025-1.250ng/ml. Inter- and intra-day precisions were no more than 10.9% with accuracy of -11.0%-10.6%, meanwhile the stable and suitable extraction recoveries were also obtained. And finally such excellent method was used to compare the pharmacokinetics of nine compounds in normal and acute blood stasis rats after oral administration of Guan-Xin-Shu-Tong capsules.