Simple High-performance Liquid Chromatography-tandem Mass Research Articles

Quantification of 3-bromopyruvate in rat plasma by HPLC-MS/MS employing precolumn derivatization and the application to a pharmacokinetics study.

A simple high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method has been developed for the determination of 3-bromopyruvate (3-BrPA) in rat plasma for the first time. The analytes were separated on a C18 column (100 × 2.1mm, 1.7μm) and a triple-quadrupole mass spectrometry equipped with an electrospray ionization source was applied for detection. 3-BrPA was extracted from rat plasma with protein precipitation, and then derivatized with 4-nitro-1,2-phenylenediamine to obtain the mass signal because 3-BrPA could not be detected in mass spectrometry. The method was fully validated according to the US Food and Drug Administration guidance. The method was linear over the concentration range 0.5-1,000.0ng/ml for 3-BrPA. The precision and accuracy, extraction recovery, and matrix effect were within acceptable limits. The method was then applied to support a pharmacokinetic study after 3-BrPA and 3-BrPA-l-Val-l-Ile (a dipeptide prodrug of 3-BrPA, 3-BrPA-l-Valine-l-isoleucine) had been administered to the Sprague-Dawley rats, respectively.

Development of a novel tandem mass spectrometry method for the quantification of eszopiclone without interference from 2-amino-5-chloropyridine and application in a pharmacokinetic study of rat

Eszopiclone (E-ZOP), a strictly controlled psychoactive drug, must be accurately quantified in biological matrices. However, because of its rapid degradation and transformation into 2-amino-5-chloropyridine (ACP) during specimen preparation, the concentration of E-ZOP in biological matrices is likely underestimated. In this study, a sensitive and simple high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method for the accurate determination of the initial concentration of E-ZOP in rat plasma was developed and validated. ACP was monitored simultaneously throughout the method validation process to ensure that it was not produced via E-ZOP hydrolysis. E-ZOP and structurally similar metabolites were stabilized in rat plasma by controlling the pH at 4.2 using a modified phosphate buffer solution (PBS) with acetic acid. Using this method, E-ZOP, ACP and the internal standard (IS), venlafaxine, were extracted from rat plasma via a simple protein precipitation and separated on a C18 column using methanol, 5 mM ammonium acetate, and 0.1 % acetic acid as the isocratic mobile phase. The validated method covered a working range from 0.1–50 ng/mL for E-ZOP, and the lower limit of detection (LLOD) for ACP was 0.2 ng/mL. In conclusion, an accurate, sensitive, and simple HPLC-MS/MS method for E-ZOP quantification was developed and successfully applied to a preclinical pharmacokinetics (PK) study in rats. The toxic product APC was effectively monitored. The HPLC-MS/MS method is a stable and sensitive quantitative method for the determination of E-ZOP in biological matrices.

Simultaneous determination of six components of Danzhi Xiaoyao Pill in beagle plasma by HPLC-MS/MS and a study of pharmacokinetic of paeoniflorin and geniposide after single-dose administration

This study was to develop a reliable and simple high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) to detect paeoniflorin, geniposide, saikosaponin b2, liquiritin, paeonol and atractylenolide Ⅲ in beagle plasma and to study pharmacokinetic of paeoniflorin and geniposide after single-dose administration of Danzhi Xiaoyao Pill (DZXY). Chromatographic separation was performed using an Agilent C18 column, and multiple reaction monitoring (MRM) mode was used. A gradient elution procedure was used with solvent A (acetonitrile) and solvent B (0.1 % formic acid-water) as mobile phases. The elution procedure was as follows: 85 % B-30 % B (0−7 min) and 30 % B-30 % B (7.1−8 min). The flow rate was 0.3 mL/min. The column temperature was 40 ℃, and the injection volume was 10 μL. The main analytical parameters of paeoniflorin, geniposide, saikosaponin b2, liquiritin, paeonol and atractylenolide Ⅲ were m/z 525→449, m/z 433→224, m/z 780→617, m/z 417→254, m/z 167→43 and m/z 249→231, respectively. Ethyl acetate was used to extract the analytes in the plasma. Standard calibration curves of six analytes showed satisfactory linearity (r2≥0.99 2) within the determined ranges. The lower limits of quantification were 0.5 ng/mL for paeoniflorin and liquiritin, 2.5 ng/mL for geniposide and saikosaponin b2 and 1.0 ng/mL for atractylenolide Ⅲ and paeonol, respectively. The intra-day and inter-day precision (RSD %) were all below 6.94 %, and the intra-day and inter-day accuracy (RE %) were within ± 6.10 %. The recovery and ME of six analytes were 85.99 %–98.10 % and 95.78%–108.06%, respectively. Additionally, the method we established in this experiment can be successfully used to study the pharmacokinetics of paeoniflorin and geniposide in beagle plasma.

Quantitative determination of risperidone, paliperidone and olanzapine in human serum by liquid chromatography-tandem mass spectrometry coupled with on-line solid-phase extraction.

A recent guideline recommends therapeutic drug monitoring for risperidone, paliperidone and olanzapine, which are frequently used second-generation antipsychotics. We developed a simple high-performance liquid chromatography-tandem mass spectrometry coupled with an online solid-phase extraction method that can be used to measure risperidone, paliperidone and olanzapine using small (40 μL) samples. The analytes were extracted from serum samples automatically pre-concentrated and purified by C8 (5 μm, 2.1 × 30 mm) solid-phase extraction cartridges, then chromatographed on an Xbidge™ C18 column (3.5 μm, 100 × 2.1 mm) thermostatted at 30°C with a mobile phase consisting of 70% acetonitrile and 30% ammonium hydroxide 1% solution at an isocratic flow rate of 0.3 mL/min, and detected with tandem mass spectrometry. The assay was validated in the concentration range from 2.5 to 160 ng/mL. Intra- and inter-day precision for all analytes was between 1.1 and 8.2%; method accuracy was between 6.6 and 7.6%. The risperidone and paliperidone assay was compared with a high-performance liquid chromatography-ultraviolet assay currently used in our hospital for risperidone and paliperidone therapeutic drug monitoring, and the results of weighted Deming regression analysis showed good agreement. For the olanzapine assay, we compared 20 samples in separate re-assays on different days; all the relative errors were within the 20% recommended limit.

Quantification and pharmacokinetics of crizotinib in rats by liquid chromatography-tandem mass spectrometry.

Crizotinib is a small molecule inhibitor of anaplastic lymphoma kinase (ALK) and can be used to treat ALK-positive nonsmall-cell lung cancer. A rapid and simple high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for the quantification of crizotinib in rat plasma using a chemical synthetic compound buspirone as the internal standard (IS). The plasma samples were pretreated by a simple protein precipitation with methanol-acetonitrile (1:1, v/v). Chromatographic separation was successfully achieved on an Agilent Zorbax XDB C18 column (2.1 × 50 mm, 3.5 µm). The gradient elution system was composed of 0.1% formic acid aqueous solution and 0.1% formic acid in methanol solution. The flow rate was set at 0.50 mL/min. The multiple reaction monitoring was based on the transitions of m/z = 450.3 → 177.1 for crizotinib and 386.2 → 122.2 for buspirone (IS). The assay was successfully validated to demonstrate the selectivity, matrix effect, linearity, lower limit of quantification, accuracy, precision, recovery and stability according to the international guidelines. The lower limit of quantification was 1.00 ng/mL in 50 μL of rat plasma. This LC-MS/MS assay was successfully applied to the quantification and pharmacokinetic study of crizotinib in rats after intravenous and oral administration of crizotinib. The oral absolute bioavailability of crizotinib in rats was 68.6 ± 9.63%. Copyright © 2015 John Wiley & Sons, Ltd.

HPLC-MS-MS Method Development and Validation of Antileishmanial Agent, S010-0269, in Hamster Serum.

A rapid, sensitive and simple high-performance liquid chromatography-tandem mass spectrometry method was developed and validated for the quantification of the antileishmanial agent, S010-0269, in hamster serum. A Discovery HS C-18 column (5 μm, 50 × 4.6 mm) maintained at 40°C was utilized for chromatographic separation with mobile phase [acetonitrile: aqueous ammonium acetate (0.01 M) buffer (85:15, v/v)] at a flow rate of 0.6 mL/min. The method requires low serum volume (20 µL) with a run time of 3.5 min. Excellent linear relationships (r ≥ 0.99) were obtained between the measured and added concentration over a range of 1-200 ng/mL. Validation parameters (accuracy, specificity, precision, recovery, matrix effect and stability) were assessed as per FDA guidelines. The precision and accuracy were acceptable as indicated by relative standard deviation ranging from 2.3 to 13.6% and bias values ranging from 1.5 to 6.5%, respectively. Moreover, the compound was found stable in hamster serum even after 30 days of storage at -80°C and being subjected to two freeze-thaw cycles. The validated method was successfully applied to the pharmacokinetic study after 10 mg/kg oral dose of S010-0269 in hamsters.