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confirmation of antibiotic residues in honey using LC-MS/MS. J. Agric. Fd Chem. , 56 , 1553–1559. Chu P.S. Multiclass determination and confirmation of antibiotic residues in honey using LC-MS/MS

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Acta Chromatographica
Authors: L. S. Teixeira, I. M. Mundim, W. C. Souza, D. R. Ramos, K. B. Bellorio and K. R. Rezende

Summary

A simple, sensitive, and rapid liquid chromatography-mass detection (LC-MS/MS) method for the analysis of betamethasone (BET) from intramuscular injection of phosphate and dipropionate BET produgs was developed for bioequivalence studies in human plasma. The calibration curve was linear over the range of concentrations (0.5–50.0 ng mL−1; r 2 = 0.99), showing a very high sensitivity without interferences at the retention times of BET (0.8 min) and the internal standard (IS) triamcinolone acetonide (0.95 min). Both drug (D) and IS were extracted from human plasma by liquid-liquid extraction, showing average recovery values of 94.0 and 98.9%, respectively. Within- and between-run precision studies demonstrated a variation coefficient <10% at all tested concentrations. Therefore, our analytical method proved to be validated according to the worldwide-accepted FDA guidelines and successfully applied for bioequivalence studies of parenteral formulations containing BET dipropionate (5 mg mL−1) and BET sodium phosphate (2 mg mL−1).

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using ultra-high performance liquid chromatography–tandem mass spectrometry (UHPLC–MS/MS). In the present study, we established a simple, sensitive, and rapid liquid chromatography (LC)–MS/MS method and validated for determination of PH in dog plasma

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A rapid and reliable liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) method was developed for the determination of acrylamide in three different local bread types; wheat bread, bran bread, whole wheat bread. Acrylamide analyses were made in crust parts of the 85 bread samples. The method was linear up to 750 μg kg–1 food with a determination coeffi cient of 0.999. Recovery rate was found 99.3% with limit of detection and limit of quantifi cation values of 1.5 μg kg–1 and 5.0 μg kg–1, respectively. Certifi ed reference materials of crisp bread were analysed and acrylamide contents of these samples were found in the range cited in the certifi cates. Statistical correlations were investigated between acrylamide contents and protein contents, reducing sugar contents, moisture contents, pH, and colour parameters (L*, a*, b*) of bread samples. Sample preparation procedure and chromatographic conditions of acrylamide analysis were investigated in more detail, and a rapid, accurate, precise, and reliable analysis method was developed.

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Summary

A new liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for simultaneous determination of glycyrrhizin, formononetin, glycyrrhetinic acid, liquiritin, isoliquiritigenin, and licochalcone A in licorice. An Eclipse Plus C18 column (I.D. 4.6 × 100 mm, 3.5 μm particle size; Agilent) was used in the analysis. Electrospray ionization (ESI)-tandem interface in the negative mode was performed, and multiple reaction monitoring (MRM) was employed with the precursor multiple reaction monitoring production combination for the determination of six analytes. The average recoveries ranged from 98.30% to 100.13% with relative standard deviations (RSDs) ≤ 1.95%, and limits of detection (LODs) ranged from 2.1 to 3.6 pg. The applicability of this analytical approach was confirmed by the successful analysis of six samples. The results indicated that the established method was validated, sensitive, and reliable for the determination of six analytes in licorice.

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Summary

Dauricine has a variety of pharmacological properties including anti-inflammatory, anti-arrhythmic, and antihypertensive effects as well as reversing multidrug resistance (MDR) of cancer cells. While its therapeutic application is increasing, its bioavailability of different administration routes has not been studied. In the present study, we developed and validated a liquid chromatography/electrospray ionization mass spectrometry method (LC-MS/MS). Using this method, we quantified dauricine in rat plasma after administration via intravenous (i.v.) injection, per oral (p.o.), and intraperitoneal injection (i.p.). Our results indicated that this method detected plasma dauricine with a good linearity in the range of 1.95–1000.00 ng/mL (r = 0.9997). The extraction method showed an average intra- and inter-day recovery of 98.21–104.35% and 98.0–103.58%, respectively. Dauricine showed a fast absorption and widespread distribution after administration in all three tested routes. After intravenous administration (2.5, 5.0, 10.0 mg/kg), the pharmacokinetics of dauricine exhibited a first-order kinetics. In addition, dauricine showed a slow elimination with a long half-life (t 1/2z) and double peaks phenomenon following p.o. and i.p. administration. Furthermore, using area under the plasma concentration-time curve (AUC), we calculated absolute bioavailability, which was over twofold higher when administered via i.p. than via p.o. administration. The newly obtained information from our study will provide important reference for dauricine dose and administration route in designing dauricine therapy for applicable diseases.

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Summary

A rapid, selective, and sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay has been proposed for the determination of aripiprazole in human plasma. The analyte and propranolol as internal standard (IS) were extracted from 200 μL of human plasma via liquid-liquid extraction using methyl tert-butyl ether under alkaline conditions. The best chromatographic separation was achieved on an Aquasil C18 (100 × 2.1 mm, 5 μm) column using methanol-deionized water containing 2 mM ammonium trifluoroacetate and 0.02% formic acid (65:35, v/v) as the mobile phase under isocratic conditions. Detection of analyte and IS was done by tandem mass spectrometry, operating in positive ion and multiple reaction monitoring (MRM) acquisition mode. The method was fully validated for its selectivity, interference check, sensitivity, carryover check, linearity, precision and accuracy, reinjection reproducibility, recovery, matrix effect, ion suppression/enhancement, stability, ruggedness, and dilution integrity. The assay was linear over the concentration range of 0.10–100 ng mL−1 for aripiprazole. The intra-batch and inter-batch precision (%CV) was ≤4.8%, while the mean extraction recovery was >96% for aripiprazole across quality control levels. The method was successfully applied to a bioequivalence study of 10 mg aripiprazole orally disintegrating tablet formulation in 27 healthy Indian subjects under fasting and fed condition. The reproducibility in the measurement of study data was demonstrated by reanalysis of 260 incurred samples.

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ng/mL and an elimination half-life of about 8 h [ 4 ]. Literature survey revealed that LCZ has been reported to be determined by ultraviolet (UV) spectrophotometry [ 3 , 5 ], liquid chromatography–tandem mass spectrometry (LC–MS/MS) in human plasma

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–tandem mass spectrometry (LC–MS/MS) method has been developed and validated for simultaneous determination of PA-824, moxifloxacin, and pyrazinamide in rat plasma and its application to a pharmacokinetic study in rats. To further clarify the DDI between the

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established a simple, sensitive, and rapid liquid chromatography–tandem mass spectrometry (LC–MS/MS) method and validated for determination of PHL in rat biological samples using resveratrol as internal standard; meanwhile, it was successfully applied to

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