Determination of gambogic acid in dog plasma by high-performance liquid chromatography for a pharmacokinetic study

A rapid, simple and sensitive high-performance liquid chromatography method for the quantification of gambogic acid in dog plasma was developed and validated. After acidification with hydrochloric acid, dog plasma was extracted with ethyl acetate and determined by HPLC. The analysis was carried out on a reversed-phase C(18) analytical column. The mobile phase consisted of a mixture of methanol-0.05% phosphoric acid (94:6, v/v), and the column temperature was maintained at 35 degrees C. A constant mobile phase flow rate of 1.0 mL/min was employed throughout the analyses. The ultraviolet detector was set at 360 nm. Chromatographic separation was achieved in less than 10 min and the calibration curve was linear over a concentration range of 0.156-20 microg/mL. The intra-assay and inter-assay variability values were less than 10.0%. The accuracy ranged from 93.0 to 104.2%. The established method has been successfully applied to a pharmacokinetic study of gambogic acid in dogs.     

HPLC analysis and pharmacokinetic study of quercitrin and isoquercitrin in rat plasma after administration of Hypericum japonicum thunb. extract

A simple HPLC method was developed for determination of quercitrin and isoquercitrin in rat plasma. Reversed-phase HPLC was employed for the quantitative analysis using kaempferol-3-O-beta-D-glucopyranoside-7-O-alpha-L-rhamnoside as an internal standard. Following extraction from the plasma samples with ethyl acetate-isopropanol (95:5, v/v), these two compounds were successfully separated on a Luna C(18) column (250 x 4.6 mm, 5 microm) with isocratic elution of acetonitrile-0.5% aqueous acetic acid (17:83, v/v) as the mobile phase. The flow-rate was set at 1 mL/min and the eluent was detected at 350 nm for both quercitrin and isoquercitrin. The method was linear over the studied ranges of 50-6000 and 50-5000 ng/mL for quercitrin and isoquercitrin, respectively. The intra- and inter-day precisions of the analysis were better than 13.1 and 13.2%, respectively. The lower limits of quantitation for quercitrin and isoquercitrin in plasma were both of 50 ng/mL. The mean extraction recoveries were 73 and 61% for quercitrin and isoquercitrin, respectively. The validated method was successfully applied to pharmacokinetic studies of the two analytes in rat plasma after the oral administration of Hypericum japonicum thunb. ethanol extract.     

Determination of paeonol in rat plasma by high-performance liquid chromatography and its application to pharmacokinetic studies following oral administration of Moutan cortex decoction

Quantification of paeonol, the principal bioactive component of Moutan cortex, in rat plasma following oral administration of Moutan cortex decoction was achieved by using a simple and sensitive high-performance liquid chromatographic method. The calibration curves for paeonol were linear in both the low (25-200 ng/mL) and the high concentration range (200-4000 ng/mL) with r(2) values of 0.9928 and 0.9993, respectively. The coefficients of variation of intra- and inter-day assays were 14.36, 6.52, 1.76, 1.25, 5.36, 3.30 and 1.42% and 12.70, 1.19, 2.98, 1.91, 1.75, 1.78 and 0.96% at concentrations of 25, 50, 100, 200, 500, 1000 and 2000 ng/mL, respectively. The recoveries of paeonol from rat plasma were found to be 101.9, 104.5, 105.4 and 101.2% for concentrations of 50, 500, 1000 and 2000 ng/mL, respectively. The paeonol plasma concentrations were fitted to two-compartment model with fi rst order absorption. The mean terminal half-lives (t(1/2)) of paeonol was 80.9 min.     

Determination and pharmacokinetic study of chlorogenic acid in rat dosed with Yin-Huang granules by RP-HPLC

A reversed-phase high-performance liquid chromatographic (RP-HPLC) method was described for the determination of chlorogenic acid (CGA) in rat plasma using protocatechuic acid as internal standard (IS). CGA in plasma was extracted with acetonitrile, which also acted as deproteinization agent. Chromatographic separation was performed on a Kromasil C18 column with methanol-0.2 m acetic acid (pH 3.0, 25:75, v/v) as mobile phase at a flow-rate of 1.0 mL/min with an operating temperature of 30 degrees C and UV detection at 300 nm. The standard curve was found to be linear over the concentration ranges of 0.4-2.5 microg/mL and 2.5-40 microg/mL, and the limit of quantification (LOQ) was 0.4 microg/mL. The analytical precision and accuracy were validated by relative standard deviation (RSD) and relative error, which were in ranges 3.14-10.78% and -2.20-5.00%, respectively. The average recovery of CGA was 87.59%. The method was successfully applied to the pharmacokinetic study of CGA in Yin-Huang granules.     

Simultaneous determination and pharmacokinetic study of gambogic acid and gambogenic acid in rat plasma after oral administration of Garcinia hanburyi extracts by LC‐MS/MS

Gambogic acid and gambogenic acid are two major bioactive components of Garcinia hanburyi, and play a pivotal role in biologic activity. In this study, a specific and sensitive liquid chromatography–tandem mass spectrometry was developed and validated for simultaneous determination of gambogic acid and gambogenic acid in rat plasma. Chromatographic separation was achieved on a C₁₈ column using an isocratic elution with methanol–10 m m ammonium acetate buffer–acetic acid (90:10:0.1, v/v/v) as the mobile phase. The detection was performed on a triple–quadrupole tandem mass spectrometer equipped with electrospray positive ionization using multiple reaction monitoring modes. The transitions monitored were m/z 629.3 [M + H]⁺ → 573.2 for gambogic acid, m/z 631.2 [M + H]⁺ → 507.2 for gambogenic acid and m/z 444.2 [M + NH₄]⁺ → 83.1 for IS. Linear calibration curves were obtained in the concentration range of 2.00–1000 ng/mL for gambogic acid and 0.500–250 ng/mL for gambogenic acid. The lower limits of quantification of gambogic acid and gambogenic acid in rat plasma were 2.00 and 0.500 ng/mL, respectively. The intra‐ and inter‐day precision (RSD) values were <11.7% and accuracy (RE) was ?10.6–12.4% at three QC levels for both analytes. The assay was successfully applied to evaluate pharmacokinetics behavior in rats after oral administration of Garcinia hanburyi extracts. Copyright © 2014 John Wiley & Sons, Ltd.     

Simultaneous determination of neochlorogenic acid,chlorogenic acid,cryptochlorogenic acid and geniposide in rat plasma by UPLC‐MS/MS and its application to a pharmacokinetic study after administration of Reduning injection

A simple, specific and sensitive ultra‐performance liquid chromatography tandem mass spectrometry (UPLC‐MS/MS) method was established and validated for simultaneous determination of neochlorogenic acid, chlorogenic acid, cryptochlorogenic acid and geniposide in rat plasma using puerarin as an internal standard (IS). Plasma samples were pretreated by a one‐step direct protein precipitation procedure with acetonitrile after acidified using as little as 50 μL plasma. Chromatographic separation was performed on an Acquity BEH C₁₈ column (100 × 2.1 mm, 1.7 µm) at a flow rate of 0.2 mL/min by a gradient elution, using 0.2% acetic acid–methanol as mobile phase. The detection was performed on a triple quadrupole tandem mass spectrometer by multiple reaction monitoring via electrospray ionization source with negative ion mode. Calibration curves showed good linearity (r > 0.995) over wide concentration ranges. The intra‐ and inter‐day precisions were <15%, and the accuracy was within ±8.0%. The validated method was successfully applied to a pharmacokinetic study of the four bioactive components in rats after intravenous administration of Reduning injection. Copyright © 2014 John Wiley & Sons, Ltd.     

Determination of tectoridin in rat plasma by high‐performance liquid chromatography and its application to pharmacokinetic studies

A simple, specific and sensitive HPLC method with UV detection was developed and validated for the determination of tectoridin in rat plasma for the first time. Chromatographic separation was performed on a Welchrom^TM C₁₈ column (150 × 4.6 mm, i.d., 5 µm) at a flow rate of 1.0 mL min^?1, using a mixture of methanol–2% HAc aqueous solution (31:69, v/v) as the mobile phase with UV detection at 266 nm. The calibration curves for tectoridin were linear over the concentration range of 1.10–274.40 µg mL^?1 in rat plasma. The intra‐ and inter‐day accuracies (RE) were within ?3.23% and 4.11%. The intra‐ and inter‐day precisions (RSD) were not more than 2.74 and 4.72%, respectively. The present method was successfully applied to the pharmacokinetic studies of tectoridin in rats after intravenous administration of three different doses. Copyright © 2009 John Wiley & Sons, Ltd.     

Determination of GL‐V9, a derivative of wogonin,in rat plasma by UPLC–MS/MS and its application to a pharmacokinetic study after oral and pulmonary administration

GL‐V9, a derivative of wogonin, shows much more potent anticancer properties than wogonin. In this study, a selective, sensitive and rapid ultra‐high‐performance liquid chromatography tandem mass spectrometry (UPLC–MS/MS) method was developed and validated for the determination of GL‐V9 in rat plasma. Plasma samples were processed using methanol to precipitate protein. Chromatographic separation of analytes was achieved on a C₁₈ column using gradient elution within 4.5 min. The mobile phase consisted of acetonitrile and water including 0.1% (v/v) formic acid and 5 mm ammonium acetate. GL‐V9 and caffeine (internal standard) were monitored by positive electrospray triple quadrupole mass spectrometer and quantified using multiple reaction monitoring (MRM) mode with the transitions of m/z 410.20 → 126.10 (GL‐V9) and 195.10 → 138.00 (IS: caffeine), respectively. Good linearity was obtained over the range of 2–1000 ng/mL (R² > 0.99) and the extraction recovery was 101.91 ± 11.34%. The intra‐ and inter‐day precision variations were small (RSD 1.35–6.96%) and the relative error (RE) of accuracy was ?7.35–6.27%. The established and validated UPLC–MS/MS method was successfully applied to study the pharmacokinetic behavior of GL‐V9 after administration through different delivery routes. The results demonstrated that pulmonary delivery exhibited a greater advantage in terms of improving bioavailability compared with oral administration.     

Determination of ferruginol in rat plasma via high‐performance liquid chromatography and its application in pharmacokinetics study

Ferruginol, a diterpene phenol, has recently received attention for its extensive pharmacological properties, including anti‐tumor, antibacterial, cardio‐protective and gastroprotective effects. In the present study, a high‐performance liquid chromatographic (HPLC) method was developed for determination of ferruginol in rat plasma and applied for the pharmacokinetics study. The HPLC assay was performed with a VP ODS‐C₁₈ column. The mobile phaseconsisted of methanol and 1% acetic acid solution (90:10, v/v). The flow rate was 1.0 mL/min, and the wavelength was set at 270 nm. This method was linear over the studied range of 0.1–10.0 µg/mL for ferruginol. The correlation coefficient was 0.9998. The intra‐day and inter‐day precisions were better than 4 and 5%, respectively. The extraction recovery and accuracy were greater than 97 and 96%, respectively. The detection limit was 30 ng/mL. The mean maximum concentration of ferruginol in rat plasma was 3.14 µg/mL at 40 min after oral administration at a dose of 20 mg/kg. Ferruginol was absorbed quickly p.o. with t_1/2ka = 14.86 min and had a high rate of elimination with t_1/2 = 41.73 min. The pharmacokinetic process of ferruginol in rat was well described with a one‐compartment model. Copyright © 2009 John Wiley & Sons, Ltd.     

A validated HPLC‐MS/MS method for determination of genipin‐1‐o‐glucuronic acid in rat plasma after administration of genipin and its application to a pharmacokinetic study

A sensitive and specific method was developed and validated for the quantitation of one major metabolite of genipin in rats plasma. The major metabolite was isolated from rat bile via semi‐preparative HPLC technology and its chemical structure was identified as genipin‐1‐o‐glucuronic acid (GNP‐GLU), which was for the first time used as a standard compound for quantitative analysis in rat plasma after administration of genipin. The application of high‐performance liquid chromatography–tandem mass spectrometry in negative mode in multiple reaction monitoring mode was investigated. Chromatographic separation was achieved on an Eclipse XDB‐C₁₈ column using a mobile phase consisting of water with 0.1% formic acid (A)–acetonitrile (B). The limit of detecation was 0.214 ng/mL and the lower limit of quantification was 0.706 ng/mL. The calibration curve was linear from 1.27 to 3810 ng/mL for plasma samples, with a correlation coefficient of 0.9924. The intra‐ and inter‐day precisions and accuracy were all within 15%. The recoveries of GNP‐GLU and puerarin were above 90.0 and 76.2%, respectively. The highly sensitive method was successfully applied to estimate pharmacokinetic parameters of GNP‐GLU following oral and intravenous administration of genipin to rats. Copyright © 2013 John Wiley & Sons, Ltd.     

反相高效液相色谱法测定罗布麻叶中的绿原酸

采用反相高效液相色谱法(RP-HPLC)在ODS Hypersil(5μm,125 mm×4mm i.d.)色谱柱上以甲醇、体积分数2%HAc为流动相测定了罗布麻叶中的绿原酸。流动相的流速为0.6 mL/min,检测波长为328 nm,建立了回归方程y=11071.10V-27.06,r=0.9999,绿原酸的回收率为98.54%。     

A solid-phase extraction method for high-performance liquid chromatographic determination of salvianolic acid B in rabbit plasma: application to pharmacokinetic study

A sensitive solid-phase extraction/high-performance liquid chromatographic method with ultraviolet detection was established for the analysis of salvianolic acid B in rabbit plasma. The analyte was separated on a reversed-phase column with trifluoroacetic acid-methanol-acetonitrile (70:10:20, v/v/v) as mobile phase at a flow rate of 1 mL/min, and ultraviolet detection at 315 nm. The calibration curve for salvianolic acid B was linear over the range 35-1400 microg/L with coefficients of correlation >0.999. The inter-day and intra-day precisions of analysis were <15%, and assay accuracy ranged from 95.3 to 109.1%. This method is suitable for determining salvianolic acid B in plasma and thus investigating the pharmacokinetics of salvianolic acid B.     

Identification of flavonoids and chlorogenic acids in elm fruits from the genus Ulmus and their antioxidant activity

Elm fruits were once an important food source in the years of famine. Research on the functional compounds in elm fruits was almost unavailable. In this study, we established an efficient high‐performance liquid chromatography method for the simultaneous separation of eight chlorogenic acids and 28 flavonoids in elm fruits for the first time. Total flavonoid contents ranged from 286 mg/100 g (Ulmus laciniata) to 1228 mg/100 g (U. pumila). High concentrations of rutin, quercetin 3‐O‐glucoside, and kaempferol derivatives were present in U. laevis, U. castaneifolia, and U. pumila, respectively. Furthermore, the fruit extracts of U. americana, U. castaneifolia, U. davidiana, and U. pumila showed higher antioxidant activity. These results suggest that fruits of these species can be used as bioresources for the extraction of the corresponding functional compounds. This work provides informative data and can be an important reference for future research on elm fruits as a renewed food resource.     

Determination of bergenin in human plasma after oral administration by HPLC-MS/MS method and its pharmacokinetic study

A highly sensitive, simple and selective high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was developed and applied to the determination of bergenin concentration in human plasma. Bergenin and the internal standard (IS) thiamphenicol in plasma were extracted with ethyl acetate, separated on a C(18 )reversed-phase column, eluted with mobile phase of acetonitrile-water, ionized by negative ion pneumatically assisted electrospray and detected in the multi-reaction monitoring mode using precursor --> product ions of m/z 327.1 --> 192 for bergenin and 354 --> 185.1 for the IS, respectively. The linear range of the calibration curve for bergenin was 0.25-60 ng mL(-1), with the lowest limit of quantification of 0.25 ng mL(-1), and the intra/inter-day relative standard deviation (RSD) was less than 10%. The method is suitable for the determination of low bergenin concentration in human plasma after therapeutic oral doses, and has been first and successfully used for its pharmacokinetic studies in healthy Chinese volunteers.     

Simultaneous determination and pharmacokinetic study of four phenol compounds in rat plasma by ultra‐high performance liquid chromatography with tandem mass spectrometry after oral administration of Echinacea purpurea extract

A rapid and sensitive assay based on ultra‐high performance liquid chromatography with electrospray ionization tandem mass spectrometry was established and validated for the simultaneous determination of cichoric acid, chlorogenic acid, quinic acid, and caffeic acid in rat plasma after oral administration of Echinacea purpurea extract using butylparaben as the internal standard. Samples were pretreated by liquid–liquid extraction with ethyl acetate. The separations for analytes were performed on an ACQUITY UPLC HSS C₁₈ column (1.8 μm 2.1 × 100 mm) using a gradient elution program with acetonitrile/10 mM ammonium acetate (pH 5.6) at a flow rate of 0.3 mL/min. The analytes were detected in multiple reaction monitoring mode with negative electrospray ionization. The lower limit of quantification of each analyte was not higher than 10.85 ng/mL. The relative standard deviation of the intraday and interday precisions was less than 14.69%. The relative errors of accuracies were in the range of –13.80 to 14.91%. The mean recoveries for extraction recovery and matrix effect were higher than 80.79 and 89.98%, respectively. The method validation results demonstrated that the proposed method was sensitive, specific, and reliable, which was successfully applied to the pharmacokinetic study of four components after oral administration of Echinacea purpurea extract.     

A New Sensitive Reversed‐phase High‐performance Liquid Chromatography Method for the Quantitative Determination of Metoclopramide in Canine Plasma

Abstract

A specific and sensitive high‐performance liquid chromatographic method was developed for the determination of metoclopramide in canine plasma. The procedure involves fast liquid–liquid extraction and analysis on an octadecyl silane (ODS) column. A preliminary pharmacokinetic study was performed by applying the developed method to a single oral administration of metoclopramide (MCP) to a dog. The validation method yielded good results regarding linearity, precision, accuracy, and specificity. The procedure is suitable for separation and quantification of MCP in canine plasma, enough to quantify 0.2 ng/ml when 0.5 ml of plasma is used. This assay procedure might be useful for the pharmacokinetic study of MCP in dogs.     

高效液相色谱法测定11种雪莲花中的紫丁香甙及芦丁

 采用高效液相色谱法测定凤毛菊属植物雪莲花中的紫丁香甙和芦丁。用乙醇超声提取 ,以乙腈 (流动相A)和水 质量分数为 36 %的乙酸水溶液 (体积比为 10 0∶4) (流动相B)进行梯度洗脱。结果表明 ,紫丁香甙线性范围为0 .0 5 2 5 μg～ 1.0 5 μg ,芦丁线性范围为 0 .0 6 5 8μg～ 1.32 μg ;不同种的雪莲花植物中紫丁香甙和芦丁的含量差异较大 ,应用雪莲花药材替代品时应慎重。     

Determination of picroside II in dog plasma by HPLC and its application in a pharmacokinetics study

A sensitive and simple high-performance liquid chromatography method with UV detection was developed and validated for determining picroside II in dog plasma. Paeoniflorin was employed as internal standard and the sample pre-treatment procedure consists of deproteinization by addition of acetonitrile. Chromatographic separations were performed on a Shimadzu VP-ODS column (250 x 4.6 mm i.d., 5 microm). The mobile phase consisted of acetonitrile-0.1% acetic acid aqueous (v/v), 23:77, v/v, at a rate of 1 mL/min. Detection was carried out at a wavelength of 266 nm. Calibration standards ranged from 0.25 to 500 microg/mL in dog plasma and the mean correlation coefficient of 0.9981 was found for the linear calibration curves (n = 6). The limit of quantification (LOQ) was 0.25 microg/mL. Intra- and inter-assay RSD ranged from 0.70 to 7.5%. Accuracy (%bias) ranged from -6.3 to 6.0%. This method was applied to the pharmacokinetic study of picroside II in dogs. The study demonstrated the plasma picroside II concentration-time curves were fitted to the two-compartment open model and showed linear pharmacokinetics.     

Rapid determination and pharmacokinetics study of lignans in rat plasma after oral administration of Schisandra chinensis extract and pure deoxyschisandrin

A simple, sensitive and rapid method for analysis of six lignans in rat plasma after oral administration of Schisandra chinensis extracts, utilizing liquid chromatography tandem mass spectrometry (LC‐MS), was established and validated. Plasma samples were prepared by one‐step protein precipitation using acetonitrile and the analytes were separated on an SB‐C₁₈ column (100 mm × 3.0 mm, 3.5 µm) with the mobile phase of acetonitrile–water at a flow‐rate of 0.8 mL/min. Analytes were determined in a single‐quadrupole mass spectrometer in the selected ion monitoring (SIM) mode using electrospray source with positive mode. The method was proved to be rapid, sensitive and reproducible, and it was successfully applied to the pharmacokinetic studies of six lignans in rat plasma after oral administration of Schisandra chinensis extracts. In this research, the pharmacokinetics of deoxyschisandrin was also studied following oral administration of the pure deoxyschisandrin. It was found that most of the pharmacokinetic parameters of deoxyschisandrin in the extract were changed significantly compared with those in monomer. The content assay also revealed that the concentrations of the lignan in the extract increased in vivo compared with the pure monomer. Some ingredients in the extract may increase the dissolution of deoxyschisandrin, delay its elimination and enhance its bioavailability in rat. Copyright © 2010 John Wiley & Sons, Ltd.