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1.
Ye X  Tao LJ  Needham LL  Calafat AM 《Talanta》2008,76(4):865-871
We developed a method using on-line solid phase extraction (SPE) coupled to high performance liquid chromatography–isotope dilution tandem mass spectrometry (HPLC–MS/MS) to measure the serum concentrations of seven environmental phenols and five parabens: bisphenol A; ortho-phenylphenol; 2,4-dichlorophenol; 2,5-dichlorophenol; 2,4,5-trichlorophenol; benzophenone-3; triclosan; and methyl-, ethyl-, propyl-, butyl-, and benzyl-parabens. The phenols and parabens present in serum were retained and concentrated on a C18 reversed-phase size-exclusion SPE column, back-eluted from the SPE column while the eluate was diluted through a mixing Tee (analyte peak focusing), separated using a pair of monolithic HPLC columns, and detected by isotope dilution-MS/MS. Sample preparation did not require protein precipitation, only dilution of the serum with 0.1 M formic acid. This method, which combines an on-line SPE with analyte peak focusing feature and the selective atmospheric pressure photoionization MS detection, resulted in limits of detection ranging from 0.1 to 0.5 ng/mL for most of the analytes. The high throughput and adequate sensitivity with yet a relative low serum volume used (100 μL) confirm that analytically it is possible to measure simultaneously these phenols and parabens with the precision and accuracy at sub-parts-per-billion levels required for biomonitoring. However, important additional factors, including validated sample collecting, handling, and storing protocols, as well as toxicokinetic data, are required if these measures are used for exposure assessment.  相似文献   

2.
Yunnan Baiyao (YNBY) is one of the best known traditional Chinese medicines. Saponins are considered to be its active components. In this study, an HPLC method was first developed for the simultaneous quantitative analysis of thirteen saponins, including five triterpenoid saponins and eight steroidal saponins, in a series of YNBY preparations, i. e., powder, capsules, aerosol, toothpaste, plaster, and adhesive bandage. The pre‐treatment methods for each dosage form were investigated and optimized. The HPLC separation was performed on a Shim‐pack C18 reversed‐phase column in gradient mode with UV detection at 203 nm. All calibration curves showed good linear regression (r2 ? 0.9981) within the test ranges. Precisions and repeatabilities of the methods were better than 4.22 and 4.78%, respectively. Recoveries were better than 90.5%, even in the analysis of the least abundant saponins in a complex YNBY plaster. HPLC–ESI‐TOF/MS was used for definite identification of compounds in the preparations. This proposed method was successfully applied to quantify the 13 bioactive constituents in 27 commercial samples to evaluate the quality of YNBY preparations. The overall results demonstrate that this method is simple, reliable, and suitable for the quality control of YNBY. Furthermore, the retention behavior of these saponins in reversed‐phase chromatography is described.  相似文献   

3.
毛细管电泳高频电导法测定虫草中的有效成份   总被引:1,自引:0,他引:1  
建立了毛细管电泳高频电导法同时测定腺苷和虫草素的方法。实验对电泳介质的种类、浓度以及操作电压和进样时间等因素进行了优化,在4mmol/L乳酸+10%异丙醇+80μg/mL羟甲基纤维素钠(pH=4.0),分离电压20.OkV的条下测定了天然虫草和人工虫草菌丝制品中的腺苷和虫草素的含量,线性范围分别为2.0μg/mL~120μg/mL和3.0μg/mL~110μg/mL,检出限分别为0.5μg/mL和1.0μg/mL。  相似文献   

4.
A sensitive and selective liquid chromatographic–tandem mass spectrometric (LC–MS/MS) method for the determination of bergenin and its phase II metabolite in rat plasma, bile and urine has been developed. Biological samples were pretreated with protein precipitation extraction procedure and enzymatic hydrolysis method was used for converting glucuronide metabolite to its free form bergenin. Detection and quantitation were performed by MS/MS using electrospray ionization and multiple reaction monitoring. Negative electrospray ionization was employed as the ionization source. Sulfamethoxazole was used as the internal standard. The separation was performed on a reverse‐phase C18 (250 × 4.6 mm, 5 μm) column with gradient elution consisting of methanol and 0.5% aqueous formic acid. The concentrations of bergenin in all biological samples were in accordance with the requirements of validation of the method. After oral administration of 12 mg/kg of the prototype drug, bergenin and its glucuronide metabolite were determined in plasma, bile and urine. Bergenin in bile was completely excreted in 24 h, and the main excreted amount of bergenin was 97.67% in the first 12 h. The drug recovery in bile within 24 h was 8.97%. In urine, the main excreted amount of bergenin was 95.69% in the first 24 h, and the drug recovery within 24 h was <22.34%. Total recovery of bergenin and its glucuronide metabolite was about 52.51% (20.31% in bile within 24 h, 32.20% in urine within 48 h). The validated method was successfully applied to pharmacokinetic and excretion studies of bergenin.  相似文献   

5.
Docetaxel, frequently used for the treatment of breast cancer, is mainly metabolized via hepatic cytochrome P450 (CYP) 3A in humans and is also a substrate of P‐glycoprotein (P‐gp). Wogonin has been shown to be able to modulate the activities of CYPs and P‐gp, and it could serve as an adjuvant chemotherapeutic agent. However, the impacts of co‐administration of wogonin and docetaxel on their pharmacokinetics have not been studied because of a lack of an analytical method for their simultaneous measurement. In the present study, we established an HPLC–MS/MS method for simultaneous measurement of wogonin and docetaxel in rat plasma, and it was then utilized to explore the pharmacokinetics of wogonin and the herb–drug interactions between wogonin and docetaxel after their combined administration in rats with mammary tumors. The rats received 10, 20 and 40 mg/kg wogonin via oral administration, with or without docetaxel intravenously administered at 10 mg/kg, and the plasma concentrations of wogonin and docetaxel were measured using the established and validated HPLC–MS/MS method. The Cmax and AUC0–t of wogonin were proportionally increased in the dose range from 10 to 40 mg/kg, suggesting a linear pharmacokinetics of wogonin. Moreover, the Cmax and AUC0–t of docetaxel and the AUC0–t of wogonin were increased after co‐administration (p < 0.05), indicating increased in vivo exposures of both wogonin and docetaxel, which might lead to an increase in not only therapeutic but also toxic effects. Thus the alterations of pharmacokinetics should be taken into consideration when wogonin and docetaxel are co‐administered.  相似文献   

6.
Schisandrin B has received much attention owing to its various biological activities. The present study was aimed at the formulation development of schisandrin B and investigation of the pharmacokinetic profiles, distribution and excretion of schisandrin B in Sprague–Dawley rats. In this study, micronized schisandrin B particles with particle size of 10–20 μm were chosen as the research object. Chromatographic separation was carried out on a BDS Hypersil C18 column (50 × 2.1 mm, i.d. 3.5 μm). Schisandrin B and deoxyschizandrin (internal standard) were detected without interference in the multiple reaction monitoring mode with positive electrospray ionization. The pharmacokinetic parameters were calculated by a noncompartmental method. The area under concentration–time curve and the maximum concentration showed a significant difference in gender. The calculated absolute oral bioavailability of schisandrin B was ~55.0% for female rat and 19.3% for male rat. Schisandrin B exhibited linear pharmacokinetics properties within the range of the tested oral dose (10, 20 and 40 mg/kg). After oral administration of schisandrin B, it was extensively distributed in ovary and adipose tissue. The result also showed very low urinary, biliary and fecal excretion of schisandrin B implying that schisandrin B was excreted mainly in the forms of metabolites.  相似文献   

7.
Plants and soil collected above an ore vein in Gasen (Austria) were investigated for total arsenic concentrations by inductively coupled plasma mass spectrometry (ICP‐MS). Total arsenic concentrations in all samples were higher than those usually found at non‐contaminated sites. The arsenic concentration in the soil ranged from ∼700 to ∼4000 mg kg−1 dry mass. Arsenic concentrations in plant samples ranged from ∼0.5 to 6 mg kg−1 dry mass and varied with plant species and plant part. Examination of plant and soil extracts by high‐performance liquid chromatography–ICP‐MS revealed that only small amounts of arsenic (<1%) could be extracted from the soil and the main part of the extractable arsenic from soil was inorganic arsenic, dominated by arsenate. Trimethylarsine oxide and arsenobetaine were also detected as minor compounds in soil. The extracts of the plants (Trifolium pratense, Dactylis glomerata, and Plantago lanceolata) contained arsenate, arsenite, methylarsonic acid, dimethylarsinic acid, trimethylarsine oxide, the tetramethylarsonium ion, arsenobetaine, and arsenocholine (2.5–12% extraction efficiency). The arsenic compounds and their concentrations differed with plant species. The extracts of D. glomerata and P. lanceolata contained mainly inorganic arsenic compounds typical of most other plants. T. pratense, on the other hand, contained mainly organic arsenicals and the major compound was methylarsonic acid. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

8.
We aimed to determine the pharmacokinetics and safety of three single oral doses (5, 10 and 15 mg) of ivabradine hemisulfate sustained‐release tablets in healthy Chinese volunteers. A total of 12 volunteers (six males and six females) were randomized to receive a single oral dose of ivabradine hemisulfate sustained‐release tablets 5, 10 or 15 mg, with a 1‐week washout between periods. Blood samples were collected at regular intervals from 0 to 48 h after drug administration, and the concentrations of ivabradine and N‐desmethyl ivabradine were determined by HPLC–tandem mass spectrometry. Pharmacokinetic parameters were estimated by non‐compartmental analysis. After administering single doses of 5, 10 and 15 mg, the mean maximum concentration (Cmax) levels of ivabradine were 4.36, 7.29 and 12.62 ng/mL, and the mean area under the curve from time 0 to 48 h (AUC0–48) values were 55.66, 101.16 and 182.09 h·ng/mL, respectively. The mean Cmax levels of N‐desmethyl ivabradine were 1.05, 2.03 and 3.16 ng/mL, and the mean AUC0–48 values were 20.61, 39.44 and 65.72 h·ng/mL, respectively. The median time of maximum concentration (Tmax) levels of ivabradine and N‐desmethyl ivabradine were 5 h for all three doses tested. The pharmacokinetic properties of ivabradine hemisulfate sustained‐release tablets were linear at doses from 5 to 15 mg. Ivabradine hemisulfate sustained‐release tablet appears to be well tolerated in these healthy volunteers.  相似文献   

9.
Monitoring gefitinib and its metabolites may help to explore the underlying mechanisms of gefitinib resistance. The concentration of gefitinib and its metabolites in tumor tissues could influence its anticancer activities more than that in the plasma. In the present study, a rapid and specific HPLC–MS/MS method was developed and validated to simultaneously determine gefitinib, M387783, M523595, M537194 and M608236 in tumor tissues of H1975 human lung cancer xenografts of nude mice. The established HPLC–MS/MS method was validated for specificity, linearity, accuracy and precision, matrix effect and recovery, carryover and dilution integrity, and analyte stability. The standard curves were linear (r2 ≥ 0.99) over the range of 0.5–100 ng/mL for M608236 and 1–200 ng/mL for gefitinib, M523595 and M537194 as well as M387783. The accuracy ranged from ?8.35 to 6.03% relative error; and the precision was <15% relative standard deviation. Recoveries (87.74–99.96%) and matrix effects (86.60–106.40%) were satisfactory in the biological matrix examined. Stability studies showed that the analytes were stable during the assay procedure and storage. Finally, the validated method was successfully applied to study the pharmacokinetics profiles for gefitinib and its metabolites in nonsmall cell lung cancer (NSCLC) xenograft mouse tumors. Meanwhile, MTT assay showed that gefitinib had a more powerful inhibitory effect than its four major metabolites in H1975 NSCLC cells. This validated HPLC–MS/MS method may be applied to help understand the mechanisms of gefitinib resistance in EGFR‐mutant nonsmall cell lung cancer.  相似文献   

10.
This study describes a direct comparison of GC and HPLC hyphenated to ICP–MS determination of tributyltin (TBT) in sediment by species-specific isotope dilution analysis (SS-IDMS). The certified reference sediment PACS-2 (NRC, Canada) and a candidate reference sediment (P-18/HIPA-1) were extracted using an accelerated solvent extraction (ASE) procedure. For comparison of GC and LC methods an older bottle of PACS-2 was used, whilst a fresh bottle was taken for demonstration of the accuracy of the methods. The data obtained show good agreement between both methods for both the PACS-2 sediment (LC–ICP–IDMS 828±87 ng g–1 TBT as Sn, GC–ICP–IDMS 848±39 ng g–1 TBT as Sn) and the P-18/ HIPA-1 sediment (LC–ICP–IDMS 78.0±9.7 ng g–1 TBT as Sn, GC–ICP–IDMS 79.2±3.8 ng g–1 TBT as Sn). The analysis by GC–ICP–IDMS offers a greater signal-to-noise ratio and hence a superior detection limit of 0.03 pg TBT as Sn, in the sediment extracts compared to HPLC–ICP–IDMS (3 pg TBT as Sn). A comparison of the uncertainties associated with both methods indicates superior precision of the GC approach. This is related to the better reproducibility of the peak integration, which affects the isotope ratio measurements used for IDMS. The accuracy of the ASE method combined with HPLC–ICP–IDMS was demonstrated during the international interlaboratory comparison P-18 organised by the Comité Consultatif pour la Quantité de Matière (CCQM). The results obtained by GC–ICP–IDMS for a newly opened bottle of PACS-2 were 1087±77 ng g–1 Sn for DBT and 876±51 ng g–1 Sn for TBT (expanded uncertainties with a coverage factor of 2), which are in good agreement with the certified values of 1090±150 ng g–1 Sn and 980±130 ng g–1 Sn, respectively.  相似文献   

11.
Marsdenia tenacissima, or Tongguanteng in Chinese, is a traditional Chinese herb and has a broad application in clinical practice for its pharmacological effects of treating asthma, pneumonia, tonsillitis, pharyngitis tumors, etc. However, few studies have reported the screening of the active components of this medicine for tumor therapy. In this work, a two‐dimensional analytical system was developed to screen antagonists of epidermal growth factor receptor (EGFR) from M. tenacissima. A fraction was retained on the EGFR cell membrane chromatography (CMC) column, separated and identified as tenacissoside G (TG), tenacissoside H (TH) and tenacissoside I (TI) by two‐dimensional HPLC–IT–TOF–MS. Molecular docking and 3‐(4,5‐dimethyl‐2‐thiazolyl)‐2,5‐diphenyl‐2‐H‐tetrazolium bromide (MTT) assay were carried out to assess the activity of TS (including TG, TH and TI). Molecular docking results showed that the binding mode of TS on EGFR is similar to that of gefitinib. The MTT assay demonstrated that gefitinib and TS (especially TI) could inhibit the growth of EGFR highly expressed cell lines in a dose‐dependent manner in the range of 5–50 μmol/L. In conclusion, the two‐dimensional EGFR/CMC–HPLC–IT–TOF–MS system could be a useful approach in drug discovery from traditional Chinese medicines for searching for potential antitumor candidates.  相似文献   

12.
13.
A simple high‐performance liquid chromatography coupled with tandem mass spectrometry method was developed and fully validated to simultaneously determine teriflunomide (TER) and its metabolite 4‐trifluoro‐methylaniline oxanilic acid (4‐TMOA) in human plasma and urine. Merely 50 μL plasma and 20 μL urine were employed in sample preparation using protein precipitation and direct dilution method, respectively. An Agilent Zorbax eclipse plus C18 column was selected to achieve rapid separation for TER and 4‐TMOA within 3 min. Electrospray ionization under multiple reaction monitoring was used to monitor the ion transitions for TER (m/z 269.0 → 159.9), 4‐TMOA (m/z 231.9 → 160.0), internal standard teriflunomide‐d4 (m/z 273.0 → 164.0) and 2‐amino‐4‐trifluoromethyl benzoic acid (m/z 203.8 → 120.1), operating in the negative ion mode. This method proved to have better accuracy and precision over concentration range of 10–5000 ng/mL in plasma as well as 10–10,000 ng/mL in urine. After a full validation, this method was successfully applied in a pharmacokinetic study of teriflunomide sodium and leflunomide in Chinese healthy volunteers.  相似文献   

14.
A simple and rapid HPLC–MS/MS method was developed and validated for simultaneous measurement of phosphocreatine and its metabolites creatine and creatinine in children's plasma. A 50 μL aliquot of plasma was prepared by protein precipitation with acetonitrile–water (1000 μL, 1:1, v/v) followed by separation on a Hypersil Gold C18 column (35°C) with gradient mobile phase consisting of 2 mm ammonium acetate aqueous solution (pH 10) and methanol at a flow rate of 0.3 mL/min and analyzed by mass spectrometry in both positive (phosphocreatine) and negative (creatine and creatinine) ion multiple reaction monitoring mode. Good linearity (r > 0.99) was obtained for the three analytes. The intra‐day and inter‐day values of CV were <5.46% (?13.09% ≤ RE ≤ 2.57%). The average recoveries of the three analytes were 70.9–97.5%. No obvious impact was found for the quantitation of three analytes in normal, hemolyzed and hyperlipemic plasma. In the end, this method was successfully applied to a pharmacokinetic study of phosphocreatine in children (six cases) with viral myocarditis of children after intravenous infusion of 2 g of the test drug. The pharmacokinetc parameters of phosphocreatine/creatine were as follows: t1/2 0.24/0.83 h, Tmax 0.49/0.55 h, Cmax 47.34/59.29 μg/mL, AUClast 17.07/59.63 h μg/mL, AUCinf 17.16/79.01 h μg/mL and MRT 0.29/0.67 h.  相似文献   

15.
A study of arsenic speciation in blood plasma of patients undergoing renal dialysis has been performed using HPLC coupled with ICP MS. It was found that the only detectable arsenic species present in the plasma was arsenobetaine. The limit of detection using an injection volume of 175 µl was found to be 0.25 ng of arsenic as arsenobetaine. Spiking experiments demonstrated recoveries of approximately 100%. In the absence of certified reference materials or an alternative technique, we believe this was the best way to demonstrate that the method was reliable and accurate. Arsenobetaine concentrations in pre‐dialysis plasma were similar to those for the healthy volunteers, although after dialysis the concentrations were significantly reduced. It is thus concluded that, except for a few patients, dialysis removed the arsenobetaine efficiently (hence preventing an accumulation of arsenic) and that no biotransformations were occurring. The exceptions to this conclusion were in a few patients whose arsenobetaine levels increased marginally after dialysis, but this was attributed to the levels both pre‐ and post‐dialysis being very close to the detection limit. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   

16.
Male factor infertility is involved in almost half of all infertile couples. Lack of the ejaculated sperm owing to testicular malfunction has been reported in 6–10% of infertile men, a condition named nonobstructive azoospermia (NOA). In this study, we investigated untargeted metabolomic profiling of the seminal plasma in NOA men using gas chromatography–mass spectrometry and advance chemometrics. In this regard, the seminal plasma fluids of 11 NOA men with TESE‐negative, nine NOA men with TESE‐positive and 10 fertile healthy men (as a control group) were collected. Quadratic discriminate analysis (QDA) technique was implemented on total ion chromatograms (TICs) for identification of discriminatory retention times. We developed multivariate classification models using the QDA technique. Our results revealed that the developed QDA models could predict the classes of samples using their TIC data. The receiver operating characteristic curves for these models were >0.88. After recognition of discriminatory retention time's asymmetric penalized least square, evolving factor analysis, correlation optimized warping and alternating least squares strategies were applied for preprocessing and deconvolution of the overlapped chromatographic peaks. We could identify 36 discriminatory metabolites. These metabolites may be considered discriminatory biomarkers for different groups in NOA.  相似文献   

17.
A simple HPLC–MS/MS method has been developed for the determination of peramivir in rat plasma in the present study. The analytes were separated on a C18 column (50 × 2.1 mm, 1.7 μm) and a triple‐quadrupole mass spectrometer equipped with an electrospray ionization source was applied for the detection. A phospholipid‐free cartridge solid‐phase extraction was used to pretreat the plasma and eliminate the endogenous phospholipid. The in‐source collision‐induced dissociation approach showed that this pretreatment could result in negligible ion suppression from the extracted sample and could produce cleaner samples when compared with the protein precipitation. The method was linear over the concentration range of 0.12–1200.0 ng/mL for peramivir. The method was validated and successfully applied to a pharmacokinetic study after peramivir was orally and intravenously administered to Sprague–Dawley rats.  相似文献   

18.
A facile, fast and specific method based on liquid chromatography–tandem mass spectrometry (LC–MS/MS) for the simultaneous quantitation of paracetamol, chlorzoxazone and aceclofenac in human plasma was developed and validated. Sample preparation was achieved by liquid–liquid extraction. The analysis was performed on a reversed‐phase C18 HPLC column (5 μm, 4.6 × 50 mm) using acetonitrile–10 mM ammonium formate pH 3.0 (65:35, v/v) as the mobile phase where atrovastatin was used as an internal standard. A very small injection volume (3 μL) was applied and the run time was 2.0 min. The detection was carried out by electrospray positive and negative ionization mass spectrometry in the multiple‐reaction monitoring mode. The developed method was capable of determining the analytes over the concentration ranges of 0.03–30.0, 0.015–15.00 and 0.15–15.00 μg/mL for paracetamol, chlorzoxazone and aceclofenac, respectively. Intraday and interday precisions (as coefficient of variation) were found to be ≤12.3% with an accuracy (as relative error) of ±5.0%. The method was successfully applied to a pharmacokinetic study of the three analytes after being orally administered to six healthy volunteers.  相似文献   

19.
A simple, rapid and robust analytical method for determining diphenylarsinic acid in human and environmental samples was developed based on a combination of hydrophilic polymer‐based gel‐permeation high‐performance liquid chromatography (HPLC) and inductively coupled plasma mass spectrometry (ICP‐MS). Hair and nail samples were digested with alkali, and liberated diphenylarsinic acid (derivative) was extracted with diethyl ether, redissolved in water and injected for HPLC–ICP‐MS analysis. Human urine, groundwater and water extracts from soils were injected for HPLC–ICP‐MS directly after filtration. Using the method, diphenylarsinic acid in a solution was quantified in 7 min duration for an analysis with a detection limit of sub‐nanograms per milliliter. The method has been applied to groundwater arsenic pollution recently uncovered in Japan. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

20.
Tanreqing capsule (TRQC) is a formulation frequently used in traditional Chinese medicine to treat pyrexia, cough, expectoration and pharyngalgia. Since the pharmacological action of traditional Chinese medicines is closely related to their complex and diverse constituents, understanding the exact composition of TRQC is important to elucidate its clinical effectiveness and mechanism of action as well as to establish quality control methods and resolve safety issues. Herein, we employed high‐performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry for the simultaneous quantitation of 23 bioactive compounds in five batches of TRQC; the analytes could be categorized into five types: organic acids (seven compounds), flavonoids (10 compounds), iridoids (two compounds), phenylethanoid glycosides (two compounds) and bile acids (two compounds). The calibration curves for all analytes showed good linearity (r > 0.9953), and the inter‐ and intra‐day precisions did not exceed 4.94 and 4.97%, respectively. The recoveries varied from 90.47% to 109.80%; the corresponding relative standard deviations (RSDs) did not exceed 4.94%; and the repeatability (RSD < 4.72%) and stability (RSD < 4.88%) were also within acceptable limits. Thus, this study can be viewed as a fundamental reference for setting comprehensive TRQC quality standards.  相似文献   

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