Extraction Condition Optimization and Identification of Phenols from Lonicerae flos

Polyphenols were obtained from the natural dried Lonicerae flos by ultrasound-assisted extraction with ethanol as the solvent.Single factor experiment and response surface methodology were employed to optimize the extraction conditions.Ultra-performance liquid chromatrography(UPLC)-tandem mass spectrometry(MS/MS)was employed to identify polyphenols based on the plant widely targeted metabolomics database in a qualitative and quantitative manner.The results showed that the optimal extraction conditions for total phenols from Lonicerae flos were ultrasound-assisted extraction with a solid-to-liquid ratio of 10∶1 g/mL and 57%ethanol at 70 W and 60°C for 11 min.The yield of total phenols extracted under the optimal conditions reached 71.08 mg/g.The phenols in Lonicerae flos were mainly chlorogenic acid isomers,and the flavonoids were mainly nobiletin,galuteolin,and homoarbutin.

Enantioseparation of Zolmitriptan by HPLC

Aim To establish a HPLC method for the separation of the enantiomers of zolmitriptan. Methods The separations were performed on Chiralcel OJ column with hexane-ethanol-diethylamine（85：15：0.2） as mobile phase at a flow rate of 0.8 mL·min^-1 and detecttion wavelength of 227 nm at 35 ℃. Several related parameters for separation were studied. Results Baseline separation （Rs 〉 1.5） was easily obtained in the case, and the R-isomer impurity in zolmitriptan was determined. Conclusion The method developed in this study has been successfully applied for quality-control purposes.

Stability of Baicalin Aqueous Solution by Validated RP-HPLC

Aim In the present study a RP-HPLC method was developed and validated toinvestigate the stability of baicalin aqueous solution. Methods The influences of temperature and pHon the stability of baicalin aqueous solution were investigated by classic homoiothermicacceleration test, and the pH for the most stable solution was determined. Results The time whenbaicalin suffered 10% loss was found to be 18.1 h, and the degradation activation energy of baicalinwas 79.1 kJ·moL^(-1) . The pH at which baicalin is most stable is 4.28. Conclusion The temperatureshould be kept at a lower level and the pH should be adjusted to near that for the most stablesolution in the production of baicalin preparations.

Evaluation on Uncertainty of Determining Aspartame in Beverage by HPLC

[Objective] The aim was to evaluate the uncertainty of determining aspartame in beverage by high performance liquid chromatography （ HPLC）. [Method] The content of aspartame in beverage was determined by HPLC, then the source of uncertainty in the whole determination process was analyzed, and each component of uncertainty was evaluated and combined. [ Result] Through 6 repeated determinations by the method in GB/T 22254-2008 ＂Determination of Aspartame in Food＂, the average content of aspartame in beverage was （0.806 ±0.038） g/kg, and k =2. The main sources of uncertainty to affect the process were the sample weighting process, the preparation process of standard solution introduced by sample constant volume and the uncertainty introduced by fitting standard curve. ①The uncertainty of standard work-solution. The combined uncertainty of standard work-solution was 0.013 9, among them the uncertainty introduced by standard sample purity was 0.005 8, the standard uncertainty introduced by standard material weighting was 1.49 ×10^4, the relative uncertainty introduced by glass apparatus calibration in the preparation process of aspartame standard reserving solution was 0. 007 88, and the uncertainty introduced by glass apparatus calibration in the preparation process of standard work-solution was 0. 009 9. ②The uncertainty introduced by the preparation process of sample specimen. Among them the relative standard uncertainty introduced by sample weighting process was 0. 009, and the uncertainty introduced by sample constant volume was 0.000 78. ③The uncertainty introduced by the fitting process of standard curve. Among them the relative uncertainty of curve fitting was 0.002 46, the uncertainty introduced by the determined results of aspartame was 0.017 0, the total combined standard uncertainty was 0.023 9, and the expanded standard uncertainty was 0.019. [ Conclusion] The uncertainty components of standard solution, standard curve and repeatability are the main sources of uncertainty, while those of sample weighting and sample constant volume account for little proportion.

HPLC Determination of Harpagoside and Cinnamic Acid in Radix Scrophulariae

A gradient HPLC method was established for the determination of harpagoside and cinnamic acid in Radix Scrophulariae (Xuanshen) and a proposition was put forward for the lowest content of the characteristic and active constituent (harpagoside) for qualified Radix Scrophulariae. The experimental conditions were as follows: Ultrasphere ODS column (250 mm 4.6 mm, 5 mm), mobile phase: acetonitrile-water (containing 1.0% acetic acid) (20:8050:50) (20 min), flow-rate 1 mLmin-1, room temperature, detection wavelength 278 nm. Twenty-eight samples of Xuan-shen (Radix Scrophulariae) from different districts of China were analyzed and the contents of harpagoside and cinnamic acid in Xuan-shen were 0.041~0.244% and 0.012~0.068% respectively. The recoveries (RSD)% were 97.13(0.80)% for harpagoside and 99.38(0.51)% for cinnamic acid. The method is simple and accurate. It can be used for the quality control of Radix Scrophulariae. We propose that the content of harpagoside in qualified Radix Scrophularia should be no less than 0.05%.

Pharmacokinetics of Oxiracetam in Healthy Volunteers

Aim To study the pharmacokinetics of oxiracetam after single and multipleintravenous administrations in healthy volunteers. Method A HPLC method was used to determine theserum concentration of oxiracetam after intravenous single dose and daily dose of 2 000 mg for 7 din ten Chinese healthy volunteers. Pharmacokinetic analysis was carried out using Drug And Statisticsoftware. Results The AUC_(0-12), AUC_(0-∞), K_e, t_(1/2), MRT after a single dose of 2 000 mgoxiracetam were 256.26 ± 16.84 μg·mL^(-1)·h, 276.74 ±18.11 μg·mL^(-1)·h, 0.18 ±0.03 h^(-1),3.84±0.64 h, and 4.39 10.39 h, and after multiple doses of oxiracetam were 259.36 ±25.43μg·mL^(-1)·h, 285.59 ±27.38 μg·mL^(-1)·h, 0.17 ±0.04 h^(-1), 4.14 ± 0.82 h, and 4.87 ±0.69 h, respectively. Conclusion The pharmacokinetic parameters of oxiracetam do not differremarkably after single and multiple intravenous administration and there is accumulation in serumafter 2 000 mg multiple intravenous administration once a day fof 7 d.

Determination of magnolol and honokiol in traditional Chinese medicine Magnolia officinalis and its preparations by liquid-phase microextraction-back extraction combined with high performance liquid chromatography

Liquid-phase microextraction with back extraction （LPME-BE） combined with high performance liquid chromatography （HPLC） was investigated for the extraction and determination of magnolol and honokiol in Magnolia officinalis, a traditional Chinese medicine （TCM）, and its pharmaceutical preparations, Huo Xiang Zheng Qi peroral liquid and Xiang Sha Yang Wei pellet. Organic solvent, donor and acceptor phases, stirring rate and extraction limes were all factors which can influence the efficiency of extraction and were all optimized during the course of this work. Linear calibration curves were obtained in concentration ranges of 1,56-156 μg/mL for magnolol and 1.10-110 μg/mL for honokiol. Detection limits （S/N = 3） were 0.10 and 0.07 μg/mL, respectively. The relative recoveries were both in the range of 98.3% - 105.1% and RSD was lower than 2.5% .

Simultaneous Determination of 2″-O-rhamnosyl Vitexin and Vitexin in Chinese Hawthorn Leaf and Its Extract by RP-HPLC

Aim To establish an RP-HPLC method for simultaneous determination of 2＂-O-rhamnosyl vitexin and vitexin in Chinese hawthorn leaf and its extract. Methods Chromatography was carfled out on Kromasil C18 column （250 mm × 4.6 mm, 5 μm）, using THF-CH3CN-H2O-H3PO4 （30 ： 5： 125 ： 0. 1） as the mobile phase at a flow rate of 1.0 mL·min^-1. The UV detection wavelength was 270 nm. Results The linear range of 2＂-O-rhamnosyl vitexin and vitexin were 0. 106 4 μg - 2. 1280 μg （ r =0. 999 1 ） and 0. 139 2μg - 2. 784 0 μg （ r =0. 999 3 ）, respectively. The average recoveries of 2＂-O-rhamnosyl vitexin and vitexin in Chinese hawthorn leaf were 99.2% （ RSD = 2.80%, n = 6） and 100.6% （ RSD = 2.84%, n = 6）, respectively. Conclusion This method is reproducible, simple, precise, and rapid for simultaneous determination of 2＂-O-rhamnosyl vitexin and vitexin in Chinese hawthorn leaf and its extract, thereby providinge the basis for quality specification of Chinese hawthorn leaf and its extract.

Pharmacokinetics of Scutellarin in Dogs

Aim To establish an RP-HPLC method for the determination of scutellarin in plasma and study its pharmacokinetics in dogs. Methods Scutellarin was given to dogs by intravenous injection and determined by RP-HPLC, the mean plasma concentration-time curve was plotted and pharmacokinetic parameters were calculated by program 3p87. Resu;ts The concentration-time curve of scutellarin could be fitted to three-compartment model with T1/2 pi, T1/2 α and T1/2 β being 1.05 ± 0.80 min, 6.99 + 2.76 min and 51.61 + 28.78 min, respectively, Vc being 880.1 + 508.3 mL, CL being 189.6 + 53.8 mL@ min- 1, and AUC0-90 and AUC0-∞ being 574.43 + 133.95 μg@ min@ mL - 1 and 599.34 ± 132.00μg@ min@mL- 1, respectively. Conclusion The fact that the concentrations of scutellarin in plasma declined rapidly after the medication suggested that the T1/2 of scutellarin should be taken into account in drug administration and preparation development.

Simultaneous Determination of Baicalin, Berberine and Rhein by HPLC in Traditional Chinese Patent Medicine Sanhuang Tablets

Aim To establish a reversed phase liquid chromatographic method forsimultaneous determination of three main medicinal constituents, baicalin, berberine and rhein, inSanhuang tablets. Methods The separation was performed on a Kromasil C_(18) column with TEA-adjusted0.02 mol·L^(-1) H_3PO_4 (pH 6.78)-acetonitrile-methanol (40 : 9 : 7) as mobile phase at aflow-rate of 1.0 mL·min^(-1), with detection at 254 ran. Considering interaction between acidic andalkaline compounds, three standard markers were added respectively and the volume of samplesolution was doubled in recovery experiments. Results Three regression equations revealed excellentlinear relationship between the peak areas and concentrations and the correlation coefficients allsurpassed 0.999 8. The average recovery was 96.1% (RSD = 2.1%) baicalin, 98.5% (RSD = 2.4%) forberberine, and 101.5% (RSD =1.3%) for rhein. Conclusion The method developed can be used to controlthe quality of Sanhuang tablets comprehensively.

High-Performance Liquid Chromatographic Determination of Nine Major Constituents in Roots of Salvia

A method of gradient-elution HPLC with UV detection was developed for theanalysis of nine major constituents of Salvia species, a commonly used TCM herb, namely danshensu,protocatechuic acid, protocatechualdehyde, salviano-lic acid B, methyltanshinone, dihydrotanshinone,cryptotanshinone, tanshinoneⅠand tanshinoneⅡ_A. In the present study, a Shimadzu CLC-ODS column(150 mm x 6 mm, 5 μm) was utilized and 0.5% formic acid (A) and acetonitrile (B) were used forgradient elution at a total flow rate of 0.8 mL· min^(-1). All calibration curves showed goodlinear regression ( r > 0.999) within test ranges. Extraction was conducted by refluxing methanol(10 mL) with dried herb (0.5 g) for 1.0 h.The assay was simple, convenient and reproducible. Theproposed method was successfully applied to the determination of nine major constituents in thirteenSalvia. species and the results showed that the contents of Salvia components vary in differentspecies and origin. Tanshinone was hardly detected in S. yunnanensis and S. prionitis, thereforethey are not suitable for clinical use as Danshen.

RP-HPLC Determination of Pinoresinol Diglucopyranoside in Qing′e Pill Extract

Aim To develop and determine pinoresinol diglucopyranoside in Qing'e Pill, atraditional Chinese compound preparation containing Eucommia ulmoides Oliv. as the principal drug,by a reverse-phase high-performance liquid chromatographic method (RP-HPLC) . Methods The extract ofQing'e Pill was refluxed with 75% ethanol, purified on an AB-8 macroporous adsorption resin columnand then injected into HPLC system. The HPLC assay was performed on an ODS analytical column with amixture of methanol-acetonitrile-water (24:3:78, V/V/V) as the mobile phase at a flow-rate of 1.0mL·min^(-1), and a UV detector set at 227 nm. Results Good linearity between peak area andconcentration was found in the range of 5.5 - 170 μg·mL^(-1) for pinoresinol diglucopyranoside ( r> 0.9998) . The average recovery was 99.3%. The intra-day assay RSD and the inter-day assay RSDwere 1.3% and 2.8%, respectively (n = 5). The content of pinoresinol diglucopyranoside in Qing'ePill was determined to be 0.446 +- 0.012 mg·g^(-1) (n = 10). Conclusion The RP-HPLC method wasproved to be sensitive, specific, accurate and precise for the determination of pinoresinoldiglucopyranoside in Qing' e Pill.

Qualitative and Quantitative Analysis of Rhizoma of Polygonum cuspidatum

Aim To establish reliable methods for evaluating the quality of rhizoma of Polygonum cuspidatum( Huzhang in Chinese). Methods TLC and HPLC were employed for the chemical identification and content determination,respectively. Results A qualitative TLC method and a quantitative HPLC method with piceid as the reference substance were established, respectively. With piceid as the reference substance and ethyl acetate-methanol-formic acid-water ( 19:3:0.5:1) as the mobile phase, a TLC method for the identification of Huzhang from the commonly used crude drugs of the same family was also set up. Conclusion The established TLC method can reasonably appraise the quality of the drug and easily distinguish Huzhang from the other commonly used crude drugs of the same family. The HPLC method for determining piceid is simple, reproducible, accurate, and feasible.

RP-HPLC determination of lycopene in microcapsules

Aim A RP- HPLC method for determination of lycopene in microcapsules was established. Methods The HPLC assay was performed on an Alltima Cls （4.6 mm × 250 mm, 5μm） column with a mixture of methanol-THF-water （66：30：4, V/V/V） as mobile phase at a flow rate of 1.5 mL·min^-1 and the UV detection wavelength was 472 nm. Results The linear range of lycopene was 3.6-18 μg·mL^-1, r = 0.999 8, the average recovery was from 99.81% to 101.06% with RSD less than 1.83%. The RSD of intra-day and interday precision were less than 3.34%. Conclusion The method is simple, accurate and suitable for the determination of lycopene in microcapsules.

Simultaneous Determination of Tetramethylpyrazine and Aspirin in a New Compound Formulation by Liquid Chromatography

Aim To establish a reversed-phase liquid chromatographic (LC) method forsimultaneous determination of tetramethylpyrazine (TMP) and aspirin in a new compound formulation.Methods Chromatographic separation of the two drugs was achieved on a Diamonsil C_(18) column, usinga binary mixture of methanol-1.5% acetic acid (35:65, V/V, pH = 3.1) as mobile phase at a flow rateof 1.0 mL·min^(-1). Results Separation was completed in less than 12 min. Benzoic acid was used asthe internal standard. Recoveries at levels corresponding to 80 % to 120 % of the label claim ofthe formulation ranged from 99.6 to 100.3 % for aspirin and from 99.9 to 101.3% for TMP. The linearrange was 12.6 - 150.9 μg·mL^(-1)(r= 0.9997, n = 5) for aspirin and 25.0- 300.0 μg·mL^(-1) (r =0.9999, n = 5) for TMP. Conclusion The method developed can be used for the simultaneousdetermination of TMP and aspirin in pharmaceutical preparations.

Classification of Chinese Traditional Drug-"Beimu" (Bulbus Fritillariae) by Pyrolysis High Resolution Gas Chromatography-Pattern Recognition

The combination of pyrolysis high resolution gas chromatography and pat- tern recognition techniques is a powerful tool for the classification of traditional Chinese drug.A study has been completed on 55 Beimu samples of five different geographic origins: Eastern China.Central China.South-western China,North-western China and North-eastern China.Principal component analysis and SIMCA are applied to effectively classifying the samples according to the origin of the plants.The chemical information contained in the high resolution gas chromatographic data is sufficient to characterize the geographic origin of sam- pies.

Study on Detection of Organochlorine Pesticide Residue in Ginseng

To investigate the residue situation of pesticides in ginseng, total 17 samples of ginseng-growing soil, ginseng roots and ginseng seeds were collected from 5 regions of Fusong County, and the contents of organochlorine pesticide residues in the samples were detected by using ultrasonic-assisted extraction and gas chromatography with acetone-ligroin as the solvent, thereby providing suitable recommendations and scientific basis for the selection of ginseng-growing soil.

Determination of Liquiritigenin, Liquiritin, Isoliquiritigenin and Isoliquiritin in Extract of Traditional Chinese Medicine Sijunzi Decoction by High-Performance Liquid Chromatography

Aim An HPLC-UV method for the analysis of Traditional Chinese Medicine （TCM） preparation, Sijunzi decoction, has been developed. Four flavonoid marker compounds, liquiritigenin, liquiritin, isoliquiritigenin, and isoliquiritin, from Radix Glycyrrhizae were quantitatively analyzed in this preparation. Methods The separation was performed on a reversed-phase C18 column by using a gradient elution with mobile phase of （A） water-formic acid （100∶0.04, V/V） （pH 3） and （B） acetonitrile. The mobile phase gradient was set from 0-5 min at 10% of B and 45 min to 90% of B. The assay was carried out at a flow rate of 0.2 mL·min-1 at room temperature with the UV detection wavelengths at 280 nm and 368 nm. Results The extract （25 mg·mL^-1） of Sijunzi decoction contains 1.47 μg·mL^-1 liquiritigenin, 16.40 μg·mL^-1 liquiritin, 0.66 μg·mL^-1 isoliquiritigenin, and 2.12 μg·mL^-1 isoliquiritin. The recoveries for the sample preparation of the markers were 102.2%, 97.7%, 100.3%, and 99.9%, respectively. Conclusion The method is simple and accurate. This study reports a routine quantitative method for the analysis of multiple components in Sijunzi decoction by HPLC.

Polyphenols from Vitis thunbergii Sieb. et Zucc.

Aim Isolation and structural elucidation of the constituents from the aerial part of Vitis thunbergii . Methods To isolate chemical constituents, column chromatography and HPLC were used. Physico chemical characterization and spectroscopic analysis were employed for structural identification. Results Eleven polyphenols were isolated and identified. Conclusion Compound 1 is a new compound and its structure was characterized to be 3,5 dimethoxyl 4 hydroxyl phenylpropanol 9 O β D glycopyranoside.

Study and Application of Fingerprints of Ginkgo biloba Leaves Preparations

Aim To establish a method for determination of Ginkgo biloba L, its extractand preparations with HPLC fingerprints, so as to control the quality of the preparations. MethodsHPLC-DAD method was used to determine the constituents in preparations. Diamonsil? C_(18) (200mm X 4.6 mm, 5 μm) was used as analytical column, and acetonitrile/KH_2PO_4 was used as mobilephase with gradient elu-tion. The column temperature was at 24 ℃. The HPLC profile of chemicalconstituents of control sample and preparations were analyzed using similarity software. Results Thefingerprints of different preparations from different companies were slightly different because ofthe different preparing procedures. Mean while, the fingerprints of different batches of the samepreparation from the same company were similar to each other and the technology of each preparationwas stable. Conclusion This method is accurate, reproducible , simple, and can be used as ananalytical method for the routine quality control of Ginkgo biloba preparations.