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Qi Y.,China Pharmaceutical University | Qi Y.,Shanghai Key Laboratory for Pharmaceutical Metabolite Research | Qi Y.,Shanghai Research Center for Drug Chinese Materia Medica Metabolism | Gu H.,East China Institute of Technology | And 17 more authors.
Evidence-based Complementary and Alternative Medicine | Year: 2013

Resina draconis (bright red resin isolated from Dracaena cochinchinensis, RD) has been clinically used for treatment of myocardial ischemia (MI) for many years. However, the mechanisms of its pharmacological action on MI are still poorly understood. This study aimed to characterize the plasma metabolic profiles of MI and investigate the mechanisms of RD on MI using ultraperformance liquid chromatography/quadrupole time-of-flight mass spectrometry-based metabolomics combined with pattern recognition methods and metabolic pathway analysis. Twenty metabolite markers characterizing metabolic profile of MI were revealed, which were mainly involved in aminoacyl-tRNA biosynthesis, phenylalanine, tyrosine, and tryptophan biosynthesis, vascular smooth muscle contraction, sphingolipid metabolism, and so forth. After RD treatment, however, levels of seven MI metabolite markers, including phytosphingosine, sphinganine, acetylcarnitine, cGMP, cAMP, L-tyrosine, and L-valine, were turned over, indicating that RD is likely to alleviate MI through regulating the disturbed vascular smooth muscle contraction, sphingolipid metabolism, phenylalanine metabolism, and BCAA metabolism. To our best knowledge, this is the first comprehensive study to investigate the mechanisms of RD for treating MI, from a metabolomics point of view. Our findings are very valuable to gain a better understanding of MI metabolic profiles and provide novel insights for exploring the mechanisms of RD on MI. © 2013 Yunpeng Qi et al.

Sun N.,China Pharmaceutical University | Sun N.,Shanghai Key Laboratory for Pharmaceutical Metabolite Research | Sun N.,Shanghai Research Center for Drug Chinese Materia Medica Metabolism | Wen J.,China Pharmaceutical University | And 14 more authors.
Journal of Pharmaceutical and Biomedical Analysis | Year: 2010

Iodiconazole is a very potent antifungal agent used to treat serious fungal infections. After transdermal administration, several factors affect the exposure of iodiconazole, resulting in large variability and demanding further elucidation of drug distribution. For determination of iodiconazole in dermal microdialysate, a new, efficient, reliable and robust ultra-fast liquid chromatography (UFLC™, Shimadzu) assay using UV detection at 230 nm has been developed and validated. Iodiconazole was separated on a Shimadzu Prominence UFLC™ C18 column (2.2 μm, 50 mm × 2.0 mm i.d.) using acetonitrile-0.025% triethylamine solution, adjusted to pH 3.6 with phosphoric acid (65:35, v/v), at a flow rate of 0.5 ml/min. The retention time was 1.37 min for iodiconazole and 1.78 min for the internal standard, an isomeric compound of iodiconazole. Intra- and inter-day precision ranged from 5.3% to 7.8% and 3.7% to 8.4%, respectively. The UFLC method was used to measure iodiconazole concentrations in microdialysis samples obtained during the calibration of laboratory-made linear probes. The validation and sample analysis results show that the method is precise, accurate and well suited to support the dermal microdialysis experiments. © 2009 Elsevier B.V. All rights reserved.

Zhao W.,China Pharmaceutical University | Zhao W.,Shanghai Key Laboratory for Pharmaceutical Metabolite Research | Zhao W.,Shanghai Research Center for Drug Chinese Materia Medica Metabolism | Yang G.,China Pharmaceutical University | And 15 more authors.
Journal of Separation Science | Year: 2014

Silymarin extracted from Silybum marianum (L.) Gaertn consists of a large number of flavonolignans, of which diastereoisomeric flavonolignans including silybin A and silybin B, and isosilybin A and isosilybin B are the main bioactive components, whose preparation from the crude extracts is still a difficult task. In this work, binary-column recycling preparative high-performance liquid chromatography systems without sample loop trapping, where two columns were switched alternately via one or two six-port switching valves, were established and successfully applied to the isolation and purification of the four diastereoisomeric flavonolignans from silymarin. The proposed system showed significant advantages over conventional preparative high-performance liquid chromatography with a single column in increasing efficiency and reducing the cost. To obtain the same amounts of products, the proposed system spends only one tenth of the time that the conventional system spends, and needs only one eleventh of the solvent that the conventional system consumes. Using the proposed system, the four diastereoisomers were successfully isolated from silymarin with purities over 98%. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Li Y.,Shanghai Ocean University | Li J.,China Pharmaceutical University | Li J.,Shanghai Key Laboratory for Pharmaceutical Metabolite Research | Chen S.,Shanghai Ocean University | And 9 more authors.
Analytical Methods | Year: 2013

In this paper, we established a micellar electrokinetic chromatography method for fast and simultaneous determination of nitrendipine and atenolol in new antihypertensive combination tablets. Buffer conditions were optimized by using a multivariate response surface methodology (RSM) established by Box-Behnken Design in terms of sodium dodecyl sulfate concentration, buffer concentration and pH of buffer. Under the optimum buffer conditions, the separation of the two drugs can be finished in 3 minutes in a 31.2 cm × 50 μm fused-silica capillary at an applied voltage of 25 kV and the temperature of 25 °C. The optimal running buffer (pH 8.9) was Na2B 4O7 (7.5 mmol L-1) and NaH2PO 4 (30 mmol L-1) containing 15 mmol L-1 sodium dodecyl sulfate. Good correlation coefficients were found (γ2 >0.999) at concentrations of 5-17.5 μg mL-1 for nitrendipine and 10-35 μg mL-1 for atenolol, respectively. All the RSD results of precision experiments were below 3%. The recoveries of nitrendipine and atenolol were 98.98-100.15% and 99.46-101.18%, respectively. The limits of detection of this method were 1 μg mL-1 and 0.5 μg mL -1 for nitrendipine and atenolol and the limits of quantification of this method were 2.5 μg mL-1 for nitrendipine and 1.5 μg mL-1 for atenolol. After the optimization, the method was successfully applied for the content uniformity test according to the United States Pharmacopeia. This journal is © The Royal Society of Chemistry 2013.

Xie R.,China Pharmaceutical University | Xie R.,Shanghai Key Laboratory for Pharmaceutical Metabolite Research | Xie R.,Shanghai Research Center for Drug Chinese Materia Medica Metabolism | Wen J.,China Pharmaceutical University | And 9 more authors.
Journal of Pharmaceutical and Biomedical Analysis | Year: 2010

An automated system using on-line solid-phase extraction and HPLC with UV detection was developed for the determination of faropenem in human plasma and urine. Analytical process was performed isocratically with two reversed-phase columns connected by a switching valve. After simple pretreatment for plasma and urine with acetonitrile, a volume of 100 μl upper layer of the plasma or urine samples was injected for on-line SPE column switching HPLC-UV analysis. The analytes were retained on the self-made trap column (Lichrospher C18, 4.6 mm × 37 mm, 25 μm) with the loading solvent (20 mM NaH2PO4 adjusted pH 3.5) at flow rate of 2 ml min-1, and most matrix materials were removed from the column to waste. After 0.5 min washing, the valve was switched to another position so that the target analytes could be eluted from trap column to analytical column in the back-flush mode by the mobile phase (acetonitrile-20 mM NaH2PO4 adjusted pH 3.5, 16:84, v/v) at flow rate of 1.5 ml min-1, and then separated on the analytical column (Ultimate™ XB-C18, 4.6 mm × 50 mm, 5 μm).The complete cycle of the on-line SPE preconcentration purification and HPLC separation of the analytes was 5 min. Calibration curves with good linearities (r = 0.9994 for plasma sample and r = 0.9988 for urine sample) were obtained in the range 0.02-5 μg ml-1 in plasma and 0.05-10 μg ml-1 in urine for faropenem. The optimized method showed good performance in terms of specificity, linearity, detection and quantification limits, precision and accuracy. The method was successfully utilized to quantify faropenem in human plasma and urine to support the clinical pharmacokinetic studies. © 2009 Elsevier B.V. All rights reserved.

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