OBJECTIVETo evaluate the quality of Polygonum perfoliatum collected from GAP planting base efficiently so as to provide scientific evidence for its GAP tending plant by HPLC fingerprinting method.

METHODAnalysis was performed on a reserved-phase column Lichrosher-C18 column (4.6 mm x 250 mm, 5 microm), A linear gradient elution of 0.2% aqueous acetic acid and acetonitrile was used for the separation.

RESULTWildlife tending P. perfoliatum was relatively stable. The chromatograms of the samples from 2011 were more accordant than those from 2010. Samples in Dafang were the most stable and had little differences during the two years. The quality of P. perfoliatum planted in the regions of sample GBG-(GD) 002 in Guiding and sample GBG-(LL) 003 in Longli were more stable and better than those from other regions.

CONCLUSIONIt is a feasible method that can be used to evaluate the quality of P. perfoliatum for GAP planting.

OBJECTIVETo investigate the effect of different chromatographic conditions on QAMS relative correlation factors (RCF) and relative retention values (RT(R)).

METHODC18 columns were used with methyl alcohol-0.4% phosphoric acid water (85: 15) as the mobile phase. The detection wavelength was 254 nm, the column temperature was 30 degrees C, and the flow rate was 1.0 mL x min(-1). The five anthraquinones in Rhei Radix et Rhizoma were selected to be the objects of study. The RCF and RT(R) among aloe-emodin, rhein, chrysophanol, physcion and emodin were determined under different chromatographic conditions.

RESULTTheir RCFs showed no significant difference.

CONCLUSIONThe RCFs among anthraquinones established by QAMS can be used as a constant in content determination of traditional Chinese medicines/patent traditional Chinese medicines.

OBJECTIVES: To establish a simple and rapid qualitative and quantitative detection method of dexmedetomidine in blood. METHODS: Blood was separated on the Allure PFP Propyl liquid chromatography column with isocratic elution after it was precipitated by acetonitrile and filtered. Qualitative and quantitative analysis of dexmedetomidine was performed using positive ion scan mode and multi-reaction monitoring mode. RESULTS: The limit of detection of dexmedetomidine in blood was 0.2 ng/mL and the limit of quantification was 0.5 ng/mL. The linearity of the method was good in the range of 0.5-1 000 ng/mL, and the correlation coefficient was greater than 0.99. The accuracy of the method was 90.34%-112.67% and the extraction recovery was 50.05%-91.08%, with no significant matrix effect. CONCLUSIONS This method is simple, selective and suitable for the qualitative and quantitative analysis of dexmedetomidine in blood, which can provide a reference for drug-facilitated cases involving dexmedetomidine.
Tandem Mass Spectrometry/methods* ; Chromatography, High Pressure Liquid/methods* ; Dexmedetomidine/analysis* ; Reproducibility of Results ; Chromatography, Liquid/methods*

Objective: To establish a method for the rapid determination of acetaminophen (APAP) in human plasma by LC-MS/MS. Methods: The plasma samples were extracted by methanol and acetonitrile (1: 1) and purified directly. C(18) column was used for sample separation. The mobile phase were methanol (5 mmol/L ammonium acetate) and water (5 mmol/L ammonium acetate). Samples were analyzed by LC MS/MS with the electrospray ionization multi reaction monitoring (MRM) mode. Results: The calibration curves of APAP was linear in the concentration range of 0~10 mg/L, the correlation coefficient (r) was greater than 0.999 0. The relative standard deviation within and between batches was less than 10%. The recovery rate were 96.81%~101.7%. The detection limit of the method was 0.1 μg/L and the lower limit of quantification was 0.3 μg/L. Conclusion: This method has strong specificity, high sensitivity and reliable determination results. It is suitable for the rapid analysis of clinical plasma samples.
Humans ; Chromatography, Liquid/methods* ; Acetaminophen ; Tandem Mass Spectrometry/methods* ; Methanol ; Chromatography, High Pressure Liquid/methods*

Chromatography, High Pressure Liquid ; methods ; Humans ; Neonicotinoids ; Pyridines ; blood

OBJECTIVETo establish fingerprint of Cortex Fraxini and provide reference for quality evaluation of Cortex Fraxini.

METHODChromatographic experiments were performed on Agilent Extend C18 column (4.6 mm x 250 mm, 5 microm), eluted with methanol and water, containing 0.4% acetic acid as the mobile phases in gradient elution. The detection wavelength was 0-60 min, 340 nm; 6-74 min, 254 nm; 74-75 min, 340 nm, and the flow rate was 1.0 mL x min(-1). Forty samples in four varieties of Cortex Fraxini were detected to establish fingerprints, respectively.

RESULTEvery parameter of the method validation complied with related rules and regulations. There were 15 common peaks in the fingerprint of 10 Fraxinus rhynchophylla samples, eleven common peaks in the fingerprint of 10 F. chinensis var. acuminata. samples, and in the fingerprint of 10 F. chinensis samples. Nineteen common peaks in the fingerprint of 10 F. stylosa samples. There were 5 common peaks in the fingerprints of 40 Cortex Fraxini samples. The similarity factors of the 10 samples of every species were all more than 0.96 compared with the control fingerprint. The similarity of the 40 Cortex Fraxini samples was more than 0.90. Four effective constituents and one unknown constituent were found in 40 samples.

CONCLUSIONThe fingerprints of F. rhynchophylla bark, F. chinensis bark, F. chinensis var. acuminata bark, F. stylosa bark and Cortex Fraxini were established. The methodological evaluation showed that the results were in accord with the technology requirements of chromatography fingerprint, and it laid a good foundation for quality control of Cortex Fraxini.

OBJECTIVETo establish a precolumn chiral derivatization method for determination of fexofenadine enantiomers, a chiral substrate of OATP1B1, in cellular model.

METHODSR-(+)-phenylethyl isocyanate was selected as chiral derivatization reagent, which was reacted with fexofenadine to form carbamate derivatives. Enantiomers were identified by LC/MS and separated by RP-HPLC.

RESULTSUnder the experimental conditions, the fexofenadine enantiomers were separated completely. The standard curve was linear over the concentration range of 25-100 ng/ml (R(2)=0.9992, 0.9989). Accuracy was 101.1% and 98.3%, intra-precision was 2.4% and 3.1%, inter-precision was 3.1% and 4.0% for D1 and D2, respectively.

CONCLUSIONThe method established is sensitive and accurate for determination of fexofenadine enantiomers in cells.

Neuronal histamine is crucially involved in a number of physiological functions as well as in neuropsychiatric diseases. Determination of histamine in biological samples is thus of importance in the clinical studies. The aim of this review is to summarize the progress or effort made in this field, with focus on the high-performance liquid chromatography.
Chromatography, High Pressure Liquid ; methods ; Histamine ; analysis ; cerebrospinal fluid ; Humans

4-Hydroxycoumarins ; blood ; Animals ; Chromatography, High Pressure Liquid ; methods

OBJECTIVETo establish a method for determining the content of alpha-lipoic acid in New Zealand rabbit plasma.

METHODSAlpha-lipoic acid in the plasma samples was purified by solid-phase extractor and analyzed on an HYPERSIL C18 column with isocratic mobile phase consisting of potassium dihydrogen phosphate-acetonitrile (50:50, v/v) at a flow rate of 1.0 ml/min and detection wavelength of 230 nm.

RESULTSThe standard curve was linear in the range of 5-100 microg/L (r=1) and the average recovery was 77.4%-82.1%. The relative standard deviations of intra-day and inter-day assay were within 1.5%-8.9%.

CONCLUSIONThe method is sensitive, accurate and simple for determining plasma alpha-lipoic acid levels in New Zealand rabbits.