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1.
BAPTA free acid was identified as the main metabolic product of 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid tetra(actoxymethyl ester) (BAPTA-AM), a neuroprotective agent in cerebral ischemia, in rats. In this paper, liquid chromatography-ultraviolet (LC-UV) and mass spectrometry/mass spectrometry (LC-MS/MS) methods were employed for the determination of BAPTA free acid in rat urine and feces and rat plasma, respectively. By liquid-liquid extraction and LC-UV analysis, a limit of quantitation of 1000 ng/ml using 0.2 ml rat urine for extraction and 250 ng/ml using 1 ml rat fecal homogenate supernatant for extraction could be reached. The assay was linear in the range of 1000-50,000 ng/ml for rat urine and 250-10,000 ng/ml for rat fecal homogenate supernatant. Because the sensitivity of the LC-UV method was apparently insufficient for evaluating the pharmacokinetic profile of BAPTA in rat plasma, a LC-MS/MS method was subsequently developed for the analysis of BAPTA free acid. By protein precipitation and LC-MS/MS analysis, the limit of quantitation was 5 ng/ml using 0.1 ml rat plasma and the linear range was 5.0-500 ng/ml. Both methods were validated and can be used to support a thorough preclinical pharmacokinetic evaluation of BAPTA-AM liposome injection.  相似文献   

2.
The paper describes a method for the sensitive and selective determination of zearalenone and its metabolites in urine, plasma and faeces of horses by high performance liquid chromatography and atmospheric pressure chemical ionisation (APCI) mass spectrometry (MS). While only one step sample clean-up by an immunoaffinity column (IAC) was sufficient for plasma samples, urine and faeces samples had to be prepared by a combination of a solid-phase extraction (SPE) and an immunoaffinity column. The method allows the simultaneous determination of zearalenone and all of its metabolites; alpha-zearalenol, beta-zearalenol, alpha-zearalanol, beta-zearalanol and zearalanone. Dideuterated zearalanone was used as internal standard for quantification and the study of the matrix effect. Recovery rates between 56 and slightly above 100% were achieved in urine samples, and more than 80% in plasma and faeces samples. The limits of detection ranged from 0.1-0.5 microg/l or microg/kg, the limits of quantification from 0.5-1.0 microg/l or microg/kg. The practical use of the method is demonstrated by the analysis of spiked and naturally contaminated urine, plasma and faeces of horses.  相似文献   

3.
Astragaloside IV is a novel cardioprotective agent extracted from the Chinese medical herb Astragalus membranaceus (Fisch) Bge. This agent is being developed for treatment for cardiovascular disease. Further development of Astragaloside IV will require detailed pharmacokinetic studies in preclinical animal models. Therefore, we established a sensitive and accurate high performance liquid chromatography (HPLC) coupled with tandem mass spectrometry (LC/MS/MS) quantitative detection method for measurement of Astragaloside IV levels in plasma, urine as well as other biological samples including bile fluid, feces and various tissues. Extraction of Astragaloside IV from plasma and other biological samples was performed by Waters OASIS(trade mark) solid phase extraction column by washing with water and eluting with methanol, respectively. An aliquot of extracted residues was injected into LC/MS/MS system with separation by a Cosmosil C18 5 microm, 150 mm x 2.0 mm) column. Acetonitrile:water containing 5 microM NaAc (40:60, v/v) was used as a mobile phase. The eluted compounds were detected by tandem mass spectrometry. The average extraction recoveries were greater than 89% for Astragaloside IV and digoxin from plasma, while extraction recovery of Astragaloside IV and digoxin from tissues, bile fluid, urine and fece ranged from 61 to 85%, respectively. Good linearity (R2>0.9999) was observed throughout the range of 10-5000 ng/ml in 0.5 ml rat plasma and 5-5000 ng/ml in 0.5 ml dog plasma. In addition, good linearity (R2>0.9999) was also observed in urine, bile fluid, feces samples and various tissue samples. The overall accuracy of this method was 93-110% for both rat plasma and dog plasma. Intra-assay and inter-assay variabilities were less than 15.03% in plasma. The lowest quantitation limit of Astragaloside IV was 10 ng/ml in 0.5 ml rat plasma and 5 ng/ml in 0.5 ml dog plasma, respectively. Practical utility of this new LC/MS/MS method was confirmed in pilot pharmacokinetic studies in both rats and dogs following intravenous administration.  相似文献   

4.
Valproyl taurinamides are a novel group of compounds that possess anticonvulsant activity. In this study a gas chromatographic micromethod was developed for the quantification of selected valproyl taurinamides and some of their metabolites in biological samples. Valproyl taurinamide (VTD), N-methyl valproyl taurinamide (M-VTD), N,N-dimethyl valproyl taurinamide (DM-VTD) and N-isopropyl valproyl taurinamide (I-VTD) were analyzed in mouse and dog plasma and in dog urine using gas chromatography. Flame ionization detection and mass spectrometric detection were compared. The plasma samples were prepared by solid-phase extraction using C(18) cartridges. The urine samples were prepared by liquid-liquid extraction. The sample volume used was 100 microl of dog plasma, 50 microl of mouse plasma and 20 microl of dog or mouse urine. The quantification range of the method was 1.5-50 mg/l in dog plasma (VTD only), 2.5-250 mg/l in mouse plasma (0.7-90 pmol injected) and 0.04-2 mg/ml in dog urine (VTD only). The inter-day precision in plasma and urine samples was around 10% for all quantified concentrations except LOQ (15-20%). The accuracy for all four compounds was between 90 and 110% within the entire concentration range. The developed method was suitable for quantification of a series of CNS-active valproyl taurineamide derivatives in biological samples at relevant in vivo concentrations.  相似文献   

5.
Sugammadex (Bridion?, Merck Sharp & Dohme Corp., Oss, The Netherlands) is a modified γ-cyclodextrin which has the ability to reverse the neuromuscular blockade induced by the steroidal neuromuscular blocking agents rocuronium and vecuronium. The objective of the current study is to describe the bioanalytical methods that have been developed and validated according to US Food and Drug Administration guidelines on bioanalytical method validation, and subsequently applied to determine total sugammadex (i.e., free sugammadex plus sugammadex bound to the neuromuscular blocking agent) in human heparinized plasma, urine and dialysate. Sugammadex was extracted from human plasma and urine using solid phase extraction with Isolute HAX 96-well extraction plates; no extraction was performed on dialysate samples. Samples from plasma, urine, and dialysate were analyzed on a Polaris? C18-A PEEK (polyaryletheretherketone) analytical column (50 mm × 4.6 mm internal diameter, 5 μm) with a linear mobile phase gradient of 0.1% (v/v) formic acid in water:methanol from 70:30 to 20:80. The flow rate was 1 mL/min with a total run time for each injection of 6 min. Tandem mass spectrometric detection was conducted using multiple reaction monitoring under negative ion mode with a turbo ion-spray interface to quantify the concentration of sugammadex. Inter- and intra-assay precision and accuracy were within pre-defined acceptance limits. The presence of rocuronium did not interfere with the assay in plasma, urine or dialysate; similarly, vecuronium did not interfere with the plasma assay (not tested for interference in urine or dialysate). Sugammadex was found to be stable in plasma, urine and dialysate in the short-term at room temperature, in the long-term at -20°C, and after several freeze/thaw cycles. The validated bioanalytical methods developed here have been successfully applied in a series of clinical studies for the determination of total sugammadex in plasma, urine and dialysate.  相似文献   

6.
A quantitative analytical method using automated on-line solid phase extraction (SPE) and liquid chromatography-electrospray tandem mass spectrometry (LC-ESI-MS/MS) for the determination of 8-OHdG (8-hydroxy-2'-deoxyguanosine) in human plasma was developed and validated. A one-step membrane extraction method for the plasma sample preparation and a C18 SPE column with simple extraction and purification were used for the on-line extraction. A C18 column was employed for LC separation and ESI-MS/MS was utilized for detection. (15)N(5)-8-OHdG ((15)N(5)-8-hydroxy-2'-deoxyguanosine) was used as an internal standard for quantitative determination. The extraction, clean-up and analysis procedures were controlled by a fully automated six-port switch valve as one strategy to reduce the matrix effect and simultaneously improve detection sensitivity. Identification and quantification were based on the following transitions: m/z 284→168 for 8-OHdG and m/z 289→173 for (15)N(5)-8-OHdG. Satisfactory recovery was obtained, and the recovery ranged from 95.1 to 106.1% at trace levels in human plasma and urine, with a CV lower than 5.4%. Values for intraday and interday precision were between 2.3 and 6.8% for plasma and between 2.7 and 4.5% for urine, respectively. Values for the method accuracy of intraday and interday assays ranged from 93.0 and 100.5% for plasma and 110.2 and 119.4% for urine, respectively. The limits of detection (LOD) and LOQ were 0.008 ng/mL and 0.02 ng/mL, respectively.The applicability of this newly developed method was demonstrated by analysis of human plasma samples for an evaluation of the future risk of oxidative stress status in human exposure to nanoparticles and other diseases.  相似文献   

7.
A high-performance liquid chromatography-mass spectrometry (HPLC-MS) method for the quantification of phenprocoumon, warfarin, and their known monohydroxylated metabolites in human plasma and urine was developed using a simple, selective solid-phase extraction scheme. Chromatographic separation was achieved on a reversed-phase Luna C18 column and step gradient elution resulted in a total run time of about 13 min. Limits of quantification (LOQ) were < or = 40 nM for the parent compounds and < or = 25 nM for the metabolites and the limit of detection (LOD) was < or = 2.5 nM for all analytes. Average recovery was 84% (+/- 3.7) and 74% (+/- 13.2) in plasma and urine, respectively. Intra- and inter-day coefficients of variation were < or = 8.6 and < or = 10.6% in plasma and urine, respectively. The method was successfully applied to the analysis of phenprocoumon samples from four healthy volunteers and should prove useful for future comparative studies of warfarin and phenprocoumon pharmacokinetics.  相似文献   

8.
A method based on liquid-liquid-liquid microextraction combined with corona discharge ion mobility spectrometry was developed for the analysis of amantadine in human urine and plasma samples. Amantadine was extracted from alkaline aqueous sample as donor phase through a thin phase of organic solvent (n-dodecane) filling the pores of the hollow fiber wall and then back extracted into the organic acceptor phase (methanol) located in the lumen of the hollow fiber. All variables affecting the extraction of analyte including acceptor organic solvent type, concentration of NaOH in donor phase, ionic strength of the sample and extraction time were studied. The linear range was 20-1000 and 5-250 ng/mL for plasma and urine, respectively (r(2)≥0.990). The limits of detection were calculated to be 7.2 and 1.6 ng/mL for plasma and urine, respectively. The relative standard deviation was lower than 8.2% for both urine and plasma samples. The enrichment factors were between 45 and 54. The method was successfully applied for the analysis of amantadine in urine and plasma samples.  相似文献   

9.
A selective and sensitive analytical method for the simultaneous measurement of dolasetron (I) and its major metabolite, MDL 74,156 (II), in human plasma and urine samples has been developed using a structural analogue, MDL 101,858, as internal standard (I.S.). The compounds were extracted from plasma and urine using solvent extraction after the addition of the I.S. Chromatographic separation was carried out on a reversed-phase HPLC column and detection and quantification was by fluorescence with excitation and emission wavelengths of 285 and 345 nm, respectively. Linear responses were obtained over concentration ranges of 5 to 1000 pmol/ml for plasma samples and 20 to 1000 pmol/ml for urine samples with correlation coefficients for the calibration curves exceeding 0.999 in all cases. Intra-day and inter-day reproducibility yielded limits of quantification of 10 pmol/ml for I and 5 pmol/ml for II in plasma and 50 pmol/ml for I and II in urine. The method has been applied to the simultaneous analysis of both compounds in plasma and urine samples coming from clinical pharmacokinetic studies.  相似文献   

10.
Accurate determinations of 5-aminolevulinic acid (ALA) and porphobilinogen (PBG) in physiologic fluids are required for the diagnosis and therapeutic monitoring of acute porphyrias. Current colorimetric methods are insensitive and over-estimate ALA and PBG due to poor specificity, while LC-MS/MS methods increase sensitivity, but have limited matrices. An LC-MS/MS method was developed to simultaneously determine ALA and PBG concentrations in fluids or tissues which were solid phase extracted, butanol derivatized, and quantitated by selective reaction monitoring using (13)C(5), (15)N-ALA and 2,4-(13)C(2)-PBG internal standards. ALA was separated from interfering compounds on a reverse phase C8-column. For ALA and PBG, the matrix effects (87.3-105%) and process efficiencies (77.6-97.8% and 37.2-41.6%, respectively) were acceptable in plasma and urine matrices. The assay was highly sensitive for ALA and PBG (LLOQ=0.05 μM with 25 μL urine or 100 μL plasma), and required ~4 h from extraction to results. ALA and PBG accuracy ranged from 88.2 to 110% (n=10); intra- and inter-assay coefficients of variations were <10% for urine and plasma. In clinical applications, patients with mutation-confirmed acute porphyrias had normal to slightly increased urinary ALA and PBG levels when asymptomatic, and high levels during acute attacks, which decreased with hemin therapy. In AIP mice, baseline ALA and PBG levels in urine, plasma, and liver were increased after phenobarbital induction 28-/63-, 42-/266-, and 13-/316-fold, respectively. This LC-MS/MS method is rapid, specific, highly sensitive, accurate, and simultaneously measures ALA and PBG in urine, plasma, and tissues permitting porphyria clinical diagnoses, therapeutic monitoring, and research.  相似文献   

11.
Two liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) methods are described, one for the quantitative determination of risperidone and the enantiomers of its active metabolite 9-hydroxyrisperidone (paliperidone) in human plasma and the other for the determination of the enantiomers of 9-hydroxyrisperidone in human urine. The plasma method is based on solid-phase extraction of 200 microl of sample on a mixed-mode sorbent, followed by separation on a cellulose-based LC column with a 13.5-min mobile phase gradient of hexane, isopropanol and ethanol. After post-column addition of 10 mM ammonium acetate in ethanol/water, detection takes place by ion-spray tandem mass spectrometry in the positive ion mode. Method validation results show that the method is sufficiently selective towards the enantiomers of 7-hydroxyrisperidone and capable of quantifying the analytes with good precision and accuracy in the concentration range of 0.2-100 ng/ml. An accelerated (run time of 4.3 min) and equally valid method for the enantiomers of 9-hydroxyrisperidone alone in plasma is obtained by increasing the mobile phase flow-rate from 1.0 to 2.0 ml/min and slightly adapting the gradient conditions. The urine method is based on the same solid-phase extraction and chromatographic approach as the accelerated plasma method. Using 100 microl of sample, (+)- and (-)-9-hydroxyrisperidone can be quantified in the concentration range 1-2000 ng/ml. The accelerated method for plasma and the method for urine can be used only when paliperidone is administered instead of risperidone, as there is insufficient separation of the 9-hydroxy enantiomers from the 7-hydroxy enantiomers, the latter ones being present only after risperidone administration.  相似文献   

12.
Sanguinarine is a quaternary benzo[c]phenanthridine alkaloid, extracted from the argemone oil, which produced severe human intoxications. To investigate the sanguinarine biotransformation, we develop a simple extraction process and a high performance liquid chromatographic separation coupled to a sensitive fluorometric detection of sanguinarine in cell culture medium, as well as in rat urine and plasma. After extraction with an acidified organic solvent, sanguinarine elution is performed within 15 min on a Nucleosil C18 column with a gradient using 0.2% formic acid/water/acetonitrile as mobile phase. Extracted and standard sanguinarine are characterized by mass spectrometry. The extraction recovery of sanguinarine is about 80% in cell culture medium and in rat urine, but lower in plasma. This convenient high performance liquid chromatography (HPLC) method allows to quantify sanguinarine over concentrations ranged 10-2000 ng ml(-1). The limit of fluorometric detection is 0.5 ng. Under these conditions, the lower limit of quantification of sanguinarine is 50 ng ml(-1) in cell culture medium and in rat urine and 100 ng ml(-1) in rat plasma. This analytical HPLC method is specific, linear and reproducible in all media and is suitable for quantitative determination of sanguinarine in biological fluids.  相似文献   

13.
A simple, sensitive and specific method for the determination of kynurenine is described. This is based on alkaline cleavage of kynurenine, followed by solvent extraction, trifluoroacetylation and gas—liquid chromatography with electron capture detection. Using this method kynurenine has been determined in urine and plasma, and for the first time in brain and cerebrospinal fluid. Increases in kynurenine in brain, plasma and urine are demonstrated following tryptophan administration to man and rat.  相似文献   

14.
A high-performance liquid chromatographic method was developed for the determination of a new non-narcotic analgesic, DA-5018 (I), in rat plasma, urine and bile samples, using propranolol for plasma samples and protriptyline for urine and bile samples as internal standards. The method involved extraction followed by injection of 100 μl of the aqueous layer onto a C18 reversed-phase column. The mobile phases were 5 mM methanesulfonic acid with 10 mM NaH2PO4 (pH 2.5)-acetonitrile, 70:30 (v/v) for plasma samples and 75:25 (v/v) for urine and bile samples. The flow-rates were 1.0 ml/min for plasma samples and 1.2 ml/min for urine and bile samples. The column effluent was monitored by a fluorescence detector with an excitation wavelength of 270 nm and an emission wavelength of 330 nm. The retention time for I was 4.8 min in plasma samples and 10.0 min in urine and bile samples. The detection limits for I in rat plasma, urine and bile were 20, 100 and 100 ng/ml, respectively. There was no interference from endogenous substances.  相似文献   

15.
Higenamine is an active ingredient of Aconite root in Chinese herbal medicine and might be used as a new agent for a pharmaceutical stress test and was approved to undergo clinical pharmacokinetic study. Therefore, there exists a need to establish a sensitive and rapid method for the determination of higenamine in human plasma and urine. This paper described a sensitive and rapid method based on liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) for the determination of higenamine in human plasma and urine. Solid-phase extraction (SPE) was used to isolate the compounds from biological matrices followed by injection of the extracts onto an Atlantis dC18 column with isocratic elution. The mobile phase was 0.05% formic acid in water-methanol (40:60, v/v). The mass spectrometry was carried out using positive electrospray ionization (ESI) and data acquisition was carried out in the multiple reaction monitoring (MRM) mode. The method was fully validated over the concentration range of 0.100-50.0 ng/mL and 1.00-500 ng/mL in plasma and urine, respectively. The lower limits of quantification (LLOQs) were 0.100 and 1.00 ng/mL in plasma and urine, respectively. Inter- and intra-batch precision was less than 15% and the accuracy was within 85-115% for both plasma and urine. Extraction recovery was 82.1% and 56.6% in plasma and urine, respectively. Selectivity, matrix effects and stability were also validated in human plasma and urine. The method was applied to the pharmacokinetic study of higenamine hydrochloride in Chinese healthy subjects.  相似文献   

16.
This article describes the development and validation of a simple solid phase extraction (SPE) and HPLC method for the extraction and the specific determination of prednisolone and hydrocortisone (cortisol) in both plasma and urine using one washing step with Oasis hydrophilic lipophilic balanced (HLB) cartridges (1 ml/30 mg, 30 microm). Recoveries of prednisolone and cortisol from plasma and urine exceeded 82%. The limit of quantification (LOQ) in plasma and urine was 9.9 and 6.7 ng/ml for cortisol, respectively, and 11.6 and 8.0 ng/ml for prednisolone, respectively. The intraday and interday precision (measured by CV%) for both prednisolone and cortisol in both plasma and urine was always less than 7%. The accuracy (measured by relative error %) for both prednisolone and cortisol in both plasma and urine was always less than 8%. The advantages of the developed method are the use of a one step washing SPE utilising HLB cartridges which do not suffer the drying out problems of conventional SPE cartridges and the time saving when compared with solvent extraction (SE), in addition to the simultaneous determination of prednisolone and cortisol in both plasma and urine.  相似文献   

17.
A modified specific, sensitive and reproducible chiral gas chromatographic (GC) method for the resolution and quantification of ethosuximide enantiomers in urine and plasma was developed. The samples were extracted by liquid-liquid extraction, using diethylether and the enantiomers were separated and quantified on a chiral gas chromatographic column (25QC2 / CYDEX- beta 0.25). The method involved the use of GC/MS instrumentation for the acquisition of data in the electron impact selective-ion monitoring mode, collecting ions characteristic of both ethosuximide and alpha, alpha - dimethyl - beta - methylsuccinimide, the internal standard and of mass-to-charge ratio (m/z) exactly equal to 55 and 70 units. The limit of quantitation of the method was 2.5 microg/ml for both urine and plasma with both enantiomers. The method proved to be linear, precise and reproducible in the 5-300 microg/ml concentration range for urine samples and in the 10-250 microg/ml concentration range for plasma samples. Future research work envisaged the application of this method in pharmacokinetic and pharmacodynamic studies.  相似文献   

18.
A high-performance liquid chromatographic analysis for the anti-AIDS drug 2',3'-dideoxyinosine (ddI) in rat plasma and urine, with a limit of detection of 0.2 μg/ml and requiring a sample size of 100 μl is described. Diluted plasma or urine samples were extracted using a C18 solid-phase extraction column. Retention of ddI on more polar solid-phase extraction columns was insufficient for sample clean-up. This method is useful for pharmacokinetic studies of ddI in small rodents.  相似文献   

19.
We describe a liquid chromatography-electrospray ionisation tandem mass spectrometry method for the qualitative and quantitative determination of the secoiridoid oleuropein and its bioactive metabolite hydroxytyrosol in rat plasma and urine. Samples were prepared by liquid-liquid extraction using ethyl acetate with a recovery for both compounds of about 100% in plasma and about 60% in urine. The chromatographic separation was performed with a RP-ODS column using a water-acetonitrile linear gradient. The calibration curve was linear for both biophenols over the range 2.5-1000 ng/ml (LOD 1.25 ng/ml) for plasma and 5-1000 ng/ml (LOD 2.5 ng/ml) for urine. Plasma concentrations of oleuropein and hydroxytyrosol were measured after oral administration of a single dose (100 mg/kg) of oleuropein. Analysis of treated rat plasma showed the presence of unmodified oleuropein, reaching a peak value of 200 ng/ml within 2 h, with a small amount of hydroxytyrosol, whereas in urine, both compounds were mainly found as glucuronides.  相似文献   

20.
An improved reverse-phase high-performance liquid chromatographic method (RP-HPLC) for the determination of a novel iron chelator CP502 (1,6-dimethyl-3-hydroxy-4-(1H)-pyridinone-2-carboxy-(N-methyl)-amide hydrochloride) in rat plasma, urine and feces was developed and validated. The separation was performed on a polymeric column using a mobile phase composed of 1mM ethylenediaminetetra-acetic acid disodium salt (EDTA), acetonitrile, methanol and methylene chloride. Separation of CP502 from plasma, urine or feces endogenous compounds was achieved by gradient elution. Retention times of CP502 and its major metabolite (glucuronide) were about 13 and 4 min, respectively. The method was validated in terms of limit of detection (LOD), limit of quantification (LOQ), selectivity (endogenous from plasma, urine or feces), linearity, extraction recovery, robustness (column selection, mobile phase composition, detection mode, internal standard (IS) selection, analyte stability), day-to-day reproducibility and system suitability (repeatability, peak symmetry and resolution). The method is applicable to bioavailability and pharmacokinetic studies of CP502 in rats.  相似文献   

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