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.

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.

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*

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*

Chromatography, High Pressure Liquid ; methods ; Electrochemistry ; Homocysteine ; blood ; Humans

OBJECTIVETo determine 4 nortriterpenoids (de-hydroxy arisanlactone D, 25-hydroxy schindilactone, schindilachone A, lancifodilactone D) in Schisandra chinensis extract by HPLC.

METHODThe analysis was performed on a waters symmetry column (4.6 mm x 250 mm, 5 microm) with the mobile phase of acetonitrile-water (33:67) at a flow rate of 1 ml x min(-1). The column temperature was set at 37 degrees C, and the detector wavelength was 264 nm.

RESULTThe linear ranges of de-hydroxy arisanlactone D, 25-hydroxy schindilactone, schindilachone A, and lancifodilactone D are 0.075-1.800, 0.098-0.980; 0.095-0.950, and 0.053-0.530 microg, respectively, and the average recoveries were 98.57%, 96.44%, 97.96%, and 97.27%, respectively.

CONCLUSIONThe four nortriterpenoids were well separated by this method, and it could be used to determine the four nortriterpenoids in Schisandra chinensis extract.

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.

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

OBJECTIVETo develop an HPLC method for simultaneous determination of four major alkaloids in Lindera aggregate.

METHODThe analysis was carried out on an Agilent ZORBAX SB-C18 column (4.6 mm x 250 mm, 5 microm) with gradient elution using acetonitrile-water (containing 0. 15% diethylamine, adjusted to pH = 3.0 with acetic acid) as mobile phase. Flow rate was 1.0 mL x min(-1) and the detection wavelength was at 289 nm.

RESULTThe calibration curves were linear over the range of 0.428-8.560 microg for boldine, 2.122-31.83 microg for norboldine, 0.760-15.20 microg for reticuline and 0.020 4-0.400 8 microg for linderegatine, respectively. The average recoveries were 99.18% for boldine, 101.0% for norboldine, 100.3% for reticuline and 99.17% for linderegatine, respectively. with RSD not more than 3.0%.

CONCLUSIONThe described method is reliable and convenient and could be used for the quality control of Lindera aggregate.

OBJECTIVETo establish a method for HPLC fingerprint determination of the triterpene acids in Poria cocos.

METHODRP-HPLC, linear gradient elution and LC/MS, etc. were used to optimize the fingerprint determination method, and identify the main peaks in the HPLC fingerprint.

RESULTA preferable method for HPLC fingerprint determination of the triterpene acids in P. cocos was established, and 9 peaks in the HPLC fingerprint were identified.

CONCLUSIONA general acquaintance of the triterpene acids in P. cocos can be obtained by using the preferable HPLC fingerprint determination method, which is useful for quality evaluation of the crud drug of P. cocos.