[Determination of eleven major components and fingerprint chromatography for Reduning injection by UPLC].

A reliable method for simultaneous determinition of eleven representative components (neochlorogenic acid, chlorogenic acid, cryptochlorogenic acid, isochlorogenic acid B, isochlorogenic acid A, isochlorogenic acid C, shanzhiside, geniposidic acid, genipin-1-ß-D-gentiobioside, geniposide and secoxyloganin) in combination of chromatographic fingerpint analysis for Reduning injection was developed by ultra high-performance liquid chromatography (UPLC). The method was performed on an Agilent ZORBAX SB-C18 anlytical column (3. 0 mm x 100 mm, 1. 8 µm) with a guard column of Agilent UPLC Guard ZORBAX SB-C18 (3.0 mm x 5 mm) at the column temperature of 30 °C. The gradient mobile phase consisted of acetonitrile (A)-0. 1% phosphoric acid (B) with a flow rate of 0. 4 mL . min-1. The injection volumn was 2 µL. The detection wavelengths were set at 324 nm and 238 nm for quantit tive analysis and 225 nm for fingerpint chromatography. Neochlorogenic acid, chlorogenic acid, cryptochlorogenic acid, isochlorogenic acid B, isochlorogenic acid A, isochlorogenic acid C, shanzhiside, geniposidic acid, genipin-1-ß-D-gentiobioside, geniposide and secoxyloganin were baseline seperated with good linearity relationships (r >0. 999) between concentration and peak areas over the linear ranges. The average recoverys of the investigated compounds were 103.5%, 100. 2%, 103. 3%, 102. 8%, 101. 3%, 102. 8%, 97. 36%, 99. 62%, 98. 16%, 102. 8%, 99. 27%, respectively. Reduning injection of forty-five batches was analyzed by UPLC finge print chromatography. Thirty batches were selected to generate the reference fringerprint chromatography with fourteen common peaks. The similarity values between the reference fringerprint chromatography and the remaining fifteen batches were higher than 0. 99. The developed method was fast, accurate and sensitive. It could be used as a reference for the quality control of multiple components determination and fingerprint chromatography for Reduning injection in future.

HPLC-DAD method for comprehensive quality control of Semen Strychni.

CONTEXT: Semen Strychni is the seed of Strychnos nux-vomica L. (Loganiaceae). Its quality control procedure remains an issue since previous reports only focused on Strychnos alkaloids. To the best of our knowledge, chlorogenic acid (a phenolic acid) and loganin (an iridoid glycoside) are selected for the first time as marker constituents of quality control for Semen Strychni because of their bioactive activity correlating with therapeutic effects. OBJECTIVE: This study aimed to develop a simple and comprehensive quantity control method for Semen Strychni. MATERIALS AND METHODS: The optimal ultrasonic extraction procedure was carried out for 45 min using 50% aqueous methanol with 1% formic acid. The satisfactory chromatographic separation was achieved on an Ultimate LP-C18 column with gradient elution using acetonitrile and water containing 30 mmol/L ammonium acetate and 1% formic acid. The high performance liquid chromatography method with diode array detector was validated for linearity, limit of detection and quantification (LOQ), precision, repeatability, accuracy and stability. RESULTS: All the calibration curves showed good linearity (r(2) ≥ 0.999). The LOQ values for chlorogenic acid, loganin, strychnine, brucine, strychnine N-oxide and brucine N-oxide were 0.54, 0.83, 0.48, 0.50, 0.52 and 0.54 µg/mL, respectively. The method was reproducible with good accuracy in the range 95.6-104.4% and relative standard deviation (RSD) values less than 4.55%. The method was then applied to determine the components of the seed coat, seed leaf, endosperm and whole seed of Semen Strychni. CONCLUSION: This newly established method is validated as a simple and practical tool for authentication and quality control of Semen Strychni.

[HPLC fingerprint of Phlomis younghusbandii].

OBJECTIVE: To establish the characteristic fingerpint from Phlomis younghustbandii. METHODS: The different collecting time and county samples of Phlomis younghusbandii were determined by HPLC. RESULTS: The HPLC-FPC of Phlomis younghusbandii was set up by establishing 14 common peaks. Accuracy, stability and repeatability of the method were good. CONCLUSION: The peaks in the spectrum were all separated perfectly, which met the regulation of HPLC-FPC.

Development and validation of a sensitive liquid chromatography-tandem mass spectrometry method for the determination of paeoniflorin in rat brain and its application to pharmacokinetic study.

A sensitive and specific method was developed and validated for the determination of paeoniflorin in rat brain with liquid chromatography-tandem mass spectrometry. Sample pretreatment involved protein precipitation following solid-phase extraction. Paeoniflorin and geniposide (internal standard) were separated isocratically on a Waters Symmetry C18 column (150 mm x 2.1 mm i.d., 5 microm), using a mobile phase of methanol/water with 0.1% formic acid (50:50, v/v) at a flow-rate of 200-300 microL/min in 4min. A Finngan LTQ tandem mass spectrometer equipped with electrospray ionization source was operated in the positive ion mode. Selective reaction monitoring was performed to quantify paeoniflorin and the internal standard at m/z transitions of 503-->381 and 411-->231, respectively. A good linearity was found in the range of 2-500 ng/mL (R(2)=0.9939). The intra- and inter-batch assay precisions (coefficient of variation, CV) at 5, 50 and 400 ng/mL (n=5) ranged from 6.3% to 9.7% and 1.2% to 7.2%, respectively, and the accuracies were from 95.9% to 101.6% and 99.4% to 102.9%, respectively. The mean recoveries of paeoniflorin were 81.2%, 80.9% and 82.3% at 5, 50 and 400 ng/mL (n=5), respectively, and the mean recovery of the internal standard was 76.7% with a concentration of 50 ng/mL (n=5). Stability studies showed that paeoniflorin was stable in different conditions. Finally, the method was successfully applied to the pharmacokinetic study of paeoniflorin in rat brain following a single subcutaneous administration (10 mg/kg) to rats.