Bosai He

Development of a UFLC-MS/MS method for simultaneous determination of six lignans of Schisandra chinensis (Turcz.) Baill. in rat plasma and its application to a comparative pharmacokinetic study in normal and insomnic rats.

Schisandra chinensis (Turcz.) Baill., a traditional Chinese medicine, has been used for treating insomnia for centuries. This paper was designed to study on the plasma pharmacokinetic for its absorption process, and to compare the pharmacokinetics of its active ingredients in normal and insomnic rats orally administrated with the prescription. Therefore, an efficient, sensitive and selective ultra fast liquid chromatography/tandem mass spectrometry (UFLC-MS/MS) method for the simultaneous determination of six sedative and hypnotic lignans (schisandrin, schisandrol B, schisantherin A, deoxyshisandrin, γ-schisandrin and gomisin N) of Schisandra chinensis (Turcz.) Baill. in rat plasma has been developed and validated. The analysis was performed on a Shim-pack XR-ODS column (75mm×3.0mm, 2.2μm) using gradient elution with the mobile phase consisting of acetonitrile and 0.1% formic acid waterat a flow rate of 0.4ml/min. The detection of the analytes was performed on 4000Q UFLC-MS/MS system with turbo ion spray source in the positive ion and multiple reaction-monitoring mode. The method was validated in plasma samples, which showed good linearity over a wide concentration range (r(2)>0.99), and obtained lower limits of quantification were 10, 1.2, 1.2, 1.2, 1.0 and 1.2ngmL(-1) for the analytes. The intra- and inter-day assay variability was less than 15% for all analytes. The mean extraction recoveries of analytes and IS from rats plasma were all more than 85.0%. The validated method has been successfully applied to comparing pharmacokinetic profiles of analytes in rat plasma. The results indicated that significant difference in pharmacokinetic parameters of the analytes was observed between two groups, while absorptions of these analytes in insomnic group were all significantly higher than those in normal group.

Comparative pharmacokinetics of three triterpene acids in rat plasma after oral administration of Poria extract and its formulated herbal preparation: GuiZhi-FuLing capsule

A sensitive liquid chromatographic-mass spectrometric technique coupled with liquid-liquid extraction method was developed and validated for simultaneous determination of dehydro-tumulosic acid, tumulosic acid and polyporic acid C in rat plasma. The analytes were separated on a Kromasil C(18) column with a total running time of 12.5 min. Author had compared the pharmacokinetics of dehydro-tumulosic acid, tumulosic acid and polyporic acid C after oral administration of the extract of Poria and its formulated herbal preparation (GuiZhi-FuLing capsule). The improved pharmacokinetic profiles of the three compounds were found in the GuiZhi-FuLing capsule, indicating the more effective absorption and the slower elimination, compared with the Poria extract. Furthermore, this study revealed that as far as the Poria extract was concerned, it is very valuable to be used as a clinical instruction of GF capsule.

A UFLC-MS/MS method for simultaneous quantitation of spinosin, mangiferin and ferulic acid in rat plasma: application to a comparative pharmacokinetic study in normal and insomnic rats.

Suan-Zao-Ren (SZR) decoction, consisting of Ziziphi Spinosae Semen, Poria, Chuanxiong Rhizoma, Anemarrhenae Rhizoma and Glycyrrhizae Radix Et Rhizoma, is a Traditional Chinese Medicine prescription, clinically used for the treatment of insomnia. The objective of this study was to develop a sensitive and reliable UFLC-MS/MS method for simultaneous quantitation of spinosin, mangiferin and ferulic acid, the main active ingredients in SZR decoction, and to compare the pharmacokinetics of these active ingredients in normal and insomnic rats orally administrated with the prescription. Analytes and IS were separated on a Shim-pack XR-ODS column (75 mm × 3.0 mm, 2.2 µm particles) using gradient elution with the mobile phase consisting of methanol and 0.1% formic acid in water at a flow rate of 0.4 mL/min. The detection of the analytes was performed on 4000Q UFLC-MS/MS system with turbo ion spray source in the negative ion and multiple reaction-monitoring mode. The lower limits of quantification were 1, 6 and 1 ng/mL for spinosin, mangiferin and ferulic acid, respectively. Intra- and inter-day precision and accuracy of analytes were well within acceptance criteria (15%). The mean extraction recoveries of analytes and IS from rats plasma were all more than 85.0%. The validated method has been successfully applied to comparing pharmacokinetic profiles of analytes in rat plasma. The results indicated that no significant difference in pharmacokinetic parameters of ferulic acid was observed between two groups, while absorptions of spinosin and mangiferin in insomnic group were significantly lower than those in normal group.

Simultaneous determination of five free and total flavonoids in rat plasma by ultra HPLC–MS/MS and its application to a comparative pharmacokinetic study in normal and hyperlipidemic rats

A simple and rapid ultra-high performance liquid chromatography-tandem mass spectrometry (uHPLC-MS/MS) method has been developed for the simultaneous determination of five free flavonoids (amentoflavone, isorhamnetin, naringenin, kaempferol and quercetin) and their total (free and conjugated) forms, and to compare the pharmacokinetics of these active ingredients in normal and hyperlipidemic rats. The free and total forms of these flavonoids were extracted by liquid-liquid extraction with ethyl acetate. The conjugated flavonoids were deconjugated by the enzyme β-Glucuronidase and Sulfatase. Chromatographic separation was accomplished on a ZORBAX Eclipse XDB-C8 USP L7 column using gradient elution. Detection was performed on a 4000Q uHPLC-MS/MS system from AB Sciex using negative ion mode in the multiple reaction monitoring (MRM) mode. The lower limits of quantification were 2.0-5.0ng/mL for all the analytes. Intra-day and inter-day precision were less than 15% and accuracy ranged from -9.3% to 11.0%, and the mean extraction recoveries of analytes and internal standard (IS) from rat plasma were all more than 81.7%. The validated method was successfully applied to a comparative pharmacokinetic study of five free and total analytes in rat plasma. The results indicated that the absorption of five total flavonoids in hyperlipidemia group were significantly higher than those in normal group with similar concentration-time curves.

A fast, sensitive, and high throughput method for the determination of cefuroxime lysine in dog plasma by UPLC-MS/MS.

In order to investigate the preclinical pharmacokinetics of cefuroxime lysine, a fast, sensitive and high throughput UPLC-ESI-MS/MS method has been developed and validated for the quantitative determination of cefuroxime in dog plasma. Cefuroxime and IS phenacetin were extracted from plasma samples by PPT or LLE procedure, and then separated on an ACQUITY UPLC™ BEH C(18) column with an isocratic elution of acetonitrile-0.1% formic acid in 10mM ammonium acetate (40:60, v/v). MRM using the fragmentation transitions of m/z 442 → 364 and 180 → 110 in positive ESI mode was performed to quantify cefuroxime and IS, respectively. The calibration curves were linear over the concentration range of 2-400 μg/ml for PPT and 0.01-5 μg/ml for LLE. The LLOQ was 0.01 μg/ml. The intra- and inter-day precisions in all samples were no more than 8.1%, while the accuracy was within ± 6.2% of nominal values. The method was successfully applied to the evaluation of pharmacokinetic parameters of cefuroxime lysine in beagle dogs.

Rapid analysis of neurotransmitters in rat brain using ultra‐fast liquid chromatography and tandem mass spectrometry: application to a comparative study in normal and insomnic rats

Neurotransmitters and their metabolites in central nervous system were known to play a significant role in sedation and hypnosis. A rapid and sensitive UFLC-MS/MS method for simultaneous determination of serotonin, 5-hydroxyindole acetic acid (5-HIAA), tryptophan (Try), dopamine (DA), norepinephrine (NE), γ-aminobutyric acid (GABA), glutamic acid (Glu) and acetylcholine (Ach) in rat brain without derivatization, ion-pairing reagent or pre-concentration was developed. Analytes and IS were separated on a Inertsil ODS-EP column (150 mm × 4.6 mm, 5 µm particles) and analyzed in a single chromatographic run in less than 9.0 min, using gradient elution with the mobile phase consisting of methanol and 0.01% acetic acid in water at a flow rate of 1.2 ml min(-1) . The detection of the analytes was performed on 4000Q UFLC-MS/MS system with turbo ion spray source in positive ion and multiple reaction monitoring mode. The developed method provided excellent linear calibration curves for the assay of analytes (R(2)  ≥ 0.9915). Limits of quantification were in the range of 1.0 ng ml(-1) to 1.0 µg ml(-1) for the analytes in rat brain. Intra- and inter-day precision and accuracy of analytes were well within acceptance criteria (15%). Mean extraction recoveries of analytes and IS from rat brain were all more than 80.0%. Furthermore, the validated method was successfully applied to comparing profiles of analytes in normal and insomnic rat brains. Results indicated that there were statistically significant differences for serotonin, 5-HIAA, DA, NE, Glu and Ach, but no significant difference for Try and GABA between two groups.

A UFLC-MS/MS method coupled with one-step protein precipitation for determination of docetaxel in rat plasma: comparative pharmacokinetic study of modified nanostructured lipid carrier.

A rapid, simple and sensitive ultra fast liquid chromatography-tandem mass spectrometry (UFLC-MS/MS) method coupled with one-step protein precipitation procedure has been developed and validated for the pharmacokinetic study of docetaxel in rat plasma to investigate the influence of polyethylene glycol (PEG) molecular weights (chain length) using in the modified formulations. Separation was achieved on a Venusil MP C18 column (100 mm × 2.1 mm, 3.0 μm) with a mobile phase consisting of methanol-water, and the total running time was 3.5min. The standard curve was linear over the range of 5-5000 ng/mL, with lower limits of quantification (LLOQ) of 5 ng/mL. The method was shown to be reliable and reproducible with intra-day precision below 10.7%, inter-day precision below 11.2%, accuracy within ±5.2%, and mean extraction recovery of 84.6-90.2%. The validated method was successfully applied to the comparative pharmacokinetic study of docetaxel in rat plasma after intravenous administration of docetaxel-loaded nanostructured lipid carrier modified by copolymers consisting of series of PEG molecular weights (2000, 4000, 10,000 Da), respectively. The results indicated that PEG-4000 possessed a better and longer circulation effect, which made the modified formulation one of the promising suspensions for the delivery of docetaxel in cancer.

Determination of catecholamines and their metabolites in rat urine by ultra‐performance liquid chromatography–tandem mass spectrometry for the study of identifying potential markers for Alzheimer's disease

In order to investigate the potential links between catecholamines (CAs) and Alzheimers disease (AD), rapid and sensitive ultra-performance liquid chromatography (UPLC)-tandem mass spectrometry (MS/MS) methods in different ionization modes for the quantification of 14 CAs and their metabolites in rat urine without derivatization or complex sample pre-treatments were developed. After addition of the internal standard, isoproterenol, the urine samples were extracted by protein precipitation and separated on an Inertsil ODS-EP column (Shimadzu, Japan) at a flow of 1.0 ml min(-1). Tandem mass spectrometric detection was performed on a 4000Q UPLC-MS/MS in the multiple reaction monitoring mode with turbo ion spray source. Tyrosine, dopamine, noradrenaline, epinephrine, 3-methoxytyramine, normetanephrine and metanephrine were determined in positive mode, while 3,4-dihyroxy-L-phenylalanine (DOPA), 3,4-dihydroxyphenylacetic acid, DL-3,4-dihydroxymandelic acid, DL-3,4-dihydroxyphenyl glycol, homovanillic acid, DL-4-hydroxy-3-methoxymandelic acid and 4-hydroxy-3-methoxy-phenylglycol were determined in negative mode. The methods were examined and were found to be precise and accurate within the linearity range of the assays. The intra-day and inter-day precision and accuracy of the analytes were well within acceptance criteria (±15%). The mean extraction recoveries of analytes and internal standard were all more than 60%. The validated methods have been successfully applied to compare CAs profiles in normal and AD rats. The results indicated the urine levels of DL-3,4-dihydroxyphenyl glycol and 4-hydroxy-3-methoxy-phenylglycol in AD rats were significantly higher than those in the normal group, and the other CAs have an opposite performance. These may attribute to the difference of some enzyme activity between rats with AD and normal. Furthermore, this may be helpful in clinical diagnostics and monitor the efficacy of AD treatment.

A UFLC-MS/MS method with a switching ionization mode for simultaneous quantitation of polygalaxanthone III, four ginsenosides and tumulosic acid in rat plasma: application to a comparative pharmacokinetic study in normal and Alzheimer's disease rats

A fast, sensitive and reliable ultra fast liquid chromatography-tandem mass spectrometry (UFLC-MS/MS) method has been developed and validated for simultaneous quantitation of polygalaxanthone III (POL), ginsenoside Rb1 (GRb1), ginsenoside Rd (GRd), ginsenoside Re (GRe), ginsenoside Rg1 (GRg1) and tumulosic acid (TUM) in rat plasma after oral administration of Kai-Xin-San, which plays an important role for the treatment of Alzheimers disease (AD). The plasma samples were extracted by liquid-liquid extraction using ethyl acetate-isopropanol (1:1, v/v) with salidrdoside as internal standard (IS). Good chromatographic separation was achieved using gradient elution with the mobile phase consisting of methanol and 0.01% acetic acid in water. The tandem mass spectrometric detection was performed in multiple reaction monitoring mode on 4000Q UFLC-MS/MS system with turbo ion spray source in a negative and positive switching ionization mode. The lower limits of quantification were 0.2-1.5 ng/ml for all the analytes. Both intra-day and inter-day precision and accuracy of analytes were well within acceptance criteria (±15%). The mean absolute extraction recoveries of analytes and IS from rat plasma were all more than 60.0%. The validated method has been successfully applied to comparing pharmacokinetic profiles of analytes in normal and AD rat plasma. The results indicated that no significant differences in pharmacokinetic parameters of GRe, GRg1 and TUM were observed between the two groups, while the absorption of POL and GRd in AD group were significantly higher than those in normal group; moreover, the GRb1 absorbed more rapidly in model group. The different characters of pharmacokinetics might be caused by pharmacological effects of the analytes.

Simultaneous quantitation of polygalaxanthone III and four ginsenosides by ultra‐fast liquid chromatography with tandem mass spectrometry in rat and beagle dog plasma after oral administration of Kai‐Xin‐San: Application to a comparative pharmacokinetic study

A fast, selective, and quantitative ultra-fast liquid chromatography with tandem mass spectrometry method has been developed and validated for the simultaneous quantitation of polygalaxanthone III, ginsenoside Rb1, ginsenoside Rd, ginsenoside Re, and ginsenoside Rg1 in the plasma of rat and beagle dog after oral administration of Kai-Xin-San. After addition of the internal standard, salidroside, the plasma samples were extracted by liquid-liquid extraction and separated on a Venusil MP C18 column with methanol/0.01% acetic acid water as mobile phase. The tandem mass spectrometric detection was performed in the multiple reaction monitoring with turbo ion spray source in a switching ionization mode. The method was examined, and found to be precise and accurate with the linearity range of the compounds. The intra- and interday precision and accuracy of the analytes were well within acceptance criteria (±15%). The mean extraction recoveries of analytes and internal standard were all >75.0%. The validated method has been successfully applied to comparing pharmacokinetic profiles of analytes in rat and beagle dog plasma. The results indicated that no significant differences were observed in pharmacokinetic parameters of ginsenoside Rg1, while the others had significant differences, which may due to the different mechanisms of absorption and metabolism.