Development and validation of an HPLC/MS/MS method for the determination of sufentanil and morphine in human plasma.

A sensitive and fast HPLC/MS/MS method for measurement of sufentanil and morphine in plasma was developed and validated. A single liquid-liquid extraction in alkaline medium was used for the cleanup of plasma, and fentanyl was added as an internal standard (IS). The analyses were carried out using a C18 column and the mobile phase acetonitrile-5 mM ammonium acetate + 0.25% formic acid (70 + 30, v/v). The triple-quadrupole mass spectrometer equipped with an electrospray source in positive mode was set up in the selective reaction monitoring mode to detect precursor --> product ion transition 387.0 > 238.0, 285.7 > 165.1, and 337.0 > 188.0 for sufentanil, morphine, and IS, respectively. The method was linear in the 0.05 (LOQ) - 500 ng/mL range for sufentanil and 10 (LOQ) - 1000 ng/mL range for morphine. Good selectivity, linearity, precision, accuracy, and robustness were obtained for the HPLC/MS/MS method. The proposed method was successfully applied for the determination of sufentanil and morphine in patients undergoing cardiac surgery.

Lipid-lowering and antiatherogenic effects of Vitex megapotamica (Spreng.) Moldenke in a mice experimental model.

ETHNOPHARMACOLOGICAL RELEVANCE: Vitex megapotamica (Spreng.) Moldenke is a deciduous tree, native of South America. Its leaves are traditionally used to treat cardiovascular diseases. This activity is related to the presence of flavonoids, the major compounds of the crude extract. AIM OF THE STUDY: This study investigated the effects of the oral administration of crude extract and standardized fractions from V. megapotamica leaves on lipid profile and on the formation of atherosclerotic plaque in C57BL/6 LDLr-KO mice treated with high-fat diet (HFD). MATERIALS AND METHODS: Male C57BL/6 LDLr-KO mice were fed with HFD (cholesterol, 1.25%) for 30 days. They were treated with hydroethanolic extract (500 or 1000mg/kg/day) or fractions (125 or 250mg/kg/day). After 30 days of treatment, it was evaluated the serum lipid profile, atherogenic index, and atherosclerotic plaque. RESULTS: All doses of the hydroethanolic extract reduced significantly the levels of total cholesterol, triglycerides, LDL-c and the atherogenic index. The n-butanolic fraction also reduced significantly the levels of total cholesterol, triglycerides, LDL-c and the atherogenic index, at all doses, with exception for the triglycerides, which only the lower dose was effective. The residual fraction reduced significantly the levels of total cholesterol, LDL-c and the atherogenic index, at all doses, with exception for the atherogenic index, which only the higher dose was effective. The atherosclerotic plaque formation was impaired only by the lower dose of the hydroethanolic extract. CONCLUSIONS: Overall, our data suggest that V. megapotamica has potential for the treatment of dyslipidemias.

Bioequivalence study of two formulations of 100 mg capsule of itraconazole. Quantification by tandem mass spectrometry.

The purpose of this study is to compare the bioavailability of two itraconazole (CAS 84625-61-6) capsule formulations. An open, randomized, two-period crossover study with a 7-day washout interval was conduced in 32 healthy volunteers. The plasma samples were obtained up to 96 h after drug administration. A sensitive and specific liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for the determination of itraconazole in human plasma. Itraconazole and ketoconazole (internal standard) were extracted from the plasma by liquid-liquid extraction using diethylether : dichloromethane (70 : 30) as extraction solvent and separated on a C8 analytical column (150 mm x 4.6 mm I.D.) maintained at 40 degrees C. The elution was performed by a constant flow rate of 1.2 mL/min and the mobile phase consisted of acetonitrile and acetic acid 0.1% (85 :15 v/v). The mass spectrometer equipped with an electrospray source in positive mode, was set up in multiple reaction monitoring, to detect parent --> production 705.0 392.0 (itraconazole) and 531.0 --> 81.70 (ketoconazole). The chromatographic separation was obtained within 3.5 min and was linear in the concentration range of 5 to 600 ng/mL. Bioequivalence between the products was determined by calculating 90% confidence intervals for the ratio of C(max) (95.02%-109.48%), AUC(0-t) (81.41%-107.77%) and AUC(0-inf) (80.85%-106.86%). These values for the test and reference products are within the 80-125% interval, proposed by FDA and EMEA. It was concluded that the proposed method was successfully applied to a pharmacokinetic study in healthy human volunteers, and results showed that the two itraconazole formulations are bioequivalent in their rate and extent of absorption.