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ABSTRACT: A simple, sensitive, selective and reproducible reversed-phase HPLC method was developed for the determination of sophoricoside in rat plasma after intravenous administration. Naringin was successfully used as internal standard (IS) for calibration. The chromatographic separation was accomplished on a reversed-phase C(18) column using acetonitrile-methanol-0.08% phosphoric acid (8:29:63, v/v/v) as mobile phase with a flow rate of 1.0 ml/min, with UV detection at 260 nm. Plasma samples were injected into the HPLC system after precipitating protein directly by methanol. Good linearity was achieved in the range of 0.0240 approximately 48.0 microg/ml (R(2)=0.9989). The limit of detection (LOD) and limit of quantification (LOQ) of this method were 0.0075 microg/ml and 0.0240 microg/ml, respectively. The absolute recoveries of sophoricoside from plasma were 95.8%, 93.2%, 98.0% at concentrations of 0.0240, 1.92, 15.0 microg/ml. The intra-day and inter-day variabilities were 3.39%~5.78% and 2.17%~4.72%, respectively. The developed method was successfully applied to the pharmacokinetic study of sophoricoside after intravenous administration of 2.5, 10 and 20 mg/kg in rats.
Yakugaku zasshi journal of the Pharmaceutical Society of Japan 12/2009; 129(12):1545-9. · 0.39 Impact Factor
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ABSTRACT: A simple, sensitive and accurate HPLC-DAD method was developed for simultaneous determination of wuchuyuamide-I, quercetin, limonin, evodiamine and rutaecarpine in Evodia rutaecarpa that has been widely used as one of the traditional Chinese medicines (TCMs). Chromatographic separations were performed on a reverse-phase C(18) column with the gradient elution of acetonitrile-water and the simultaneous detection at five wavelengths. Good linear behaviors over the investigated concentration ranges were observed with the values of r higher than 0.999 for all the analytes. The recoveries measured at three levels varied from 98.77 to 102.36%. The validated method was successfully applied for the simultaneous determination of the five chemical constituents in 36 batches of samples collected from different regions or time that were investigated and authenticated as E. rutaecarpa (Juss.) Benth. Hierarchical clustering analysis (HCA) and principal components analysis (PCA) were performed to differentiate and classify the samples based on the contents of the five characteristic constituents. The total contents of evodiamine and rutaecarpine in different samples were calculated and the blending method proposed was demonstrated to be very useful in saving resources and in guiding rational herb use.
Journal of Pharmaceutical and Biomedical Analysis 10/2008; 48(4):1230-6. · 2.97 Impact Factor
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ABSTRACT: A simple reversed-phase high performance liquid chromatographic method was developed for the determination of dencichine in sanchi on a porous graphitic carbon (PGC) column. The effects of different buffers, buffer concentrations, pH values of mobile phase and mobile phase compositions as well as column temperatures on the retention of dencichine were studied. The retention mechanism of dencichine on a porous graphitic carbon column seems to be mainly hydrophobic interaction according to the study. The chromatographic method developed was used to determine dencichine in sanchi. The calibration curve was linear in the range of about 0.22 - 4.4 microg (r = 0.999 9) and the recovery for the extract was 99.5% with the relative standard deviation of 2.2% (n = 9).
Se pu = Chinese journal of chromatography / Zhongguo hua xue hui 12/2007; 25(6):834-7.
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ABSTRACT: Volatile components of Curcuma sichuanensis X. X. Chen growing in Sichuan, China, were extracted by steam distillation and analyzed by using gas chromatography and gas chromatography-mass spectrometry. A total of 44 volatile essential oil components were identified in the extract of C. sichuanensis X. X. Chen, representing 87.1% of the total integrated chromatographic peaks. The major compounds were found to be epi-curzerenone (26.9%), germacrone (12.4%), isocurcumenol (9.7%), beta-elemene (6.4%) and curzerene (6.2%). The results of semi-quantitative analysis indicated that levels of total sesquiterpene fraction (85.4%) were more than 55 times higher than those of monoterpene components (1.5%).
Journal of Pharmaceutical and Biomedical Analysis 02/2007; 43(2):440-4. · 2.97 Impact Factor
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ABSTRACT: An analytical method was developed for the determination of enantiomers of dencichine in plasma. Sample extraction from plasma was achieved by a solid-phase extraction (SPE) procedure using a C(18) cartridge, with carbocisteine as the internal standard. Plasma was deproteinized using inorganic acid and derivatizated before the SPE. Chiral separation of dencichine enantiomers was achieved by pre-column derivatization using o-phthaldialdehyde (OPA) and the chiral thiol N-isobutanoyl-L-cysteine (NIBC) to form diastereoisomeric isoindole derivatives that were separable by ODS column using a gradient solvent programme. The column eluent was monitored using mass spectrometry (MS). The conditions of MS detection were optimized, and selected ion monitoring was used to selectively detect D-dencichine and its arrangement isomer. High sensitivity and selectivity were obtained using this method. The limit of detection was determined to be 10 ng/ml for D-dencichine and 8 ng/ml for L-dencichine in plasma. The linearity was demonstrated over a wide range of concentrations, from 0.5 to 50 microg/ml for both enatiomers. The intra- and inter-day precision (C.V.), studied at four concentrations, was less than 7.0%. No interferences from endogenous amino acids and isomers of dencichine were found. The method was suitable for pharmacokinetic studies of dencichine enantiomers.
Journal of Chromatography B 09/2006; 840(2):124-31. · 2.89 Impact Factor
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Se pu = Chinese journal of chromatography / Zhongguo hua xue hui 02/2006; 24(1):105.
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ABSTRACT: Solid-phase extraction (SPE) coupled with gas chromatography/mass spectrometry (GC/MS) was used to determine the fosthiazate residue in water samples. The water samples were first filtered through cellulose filters (0.45 microm pore size). A 100 mL volume of filtered water, in which 1 mL of methanol has been added, was then passed through a pre-conditioned 3 cm C18 cartridge at a flow-rate of 1.5 mL/min. Elution was performed by 1 mL of methanol. The eluant was finally dried under reduced pressure for solvent evaporation. The volume was quantitatively adjusted to 0.5 mL with methanol. The analysis was carried out on GC/MS. The mass spectrometer was operated in selected ion monitoring (SIM) mode. According to mass spectrum of fosthiazate, three selected ions at m/z of 126, 195, 283, respectively, were monitored for identification and quantification. High sensitivity and selectivity were achieved by using this method. The limit of detection for fosthiazate in water samples was determined to be 56.4 ng/L. The linearity was demonstrated over a wide range of concentrations covering from 0.282 to 141 microg/L. The recoveries were more than 85.5% and the relative standard deviations for the overall procedure were less than 4.42%. The fosthiazate residue was detected in the water samples from a pool near cropland where fosthiazate was used. The results demonstrate the suitability of the SPE-GC/MS approach for the analysis of fosthiazate in water.
Se pu = Chinese journal of chromatography / Zhongguo hua xue hui 12/2004; 22(6):655-7.
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Se pu = Chinese journal of chromatography / Zhongguo hua xue hui 04/2004; 22(2):182.
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ABSTRACT: A method for the extraction of baicalin from Radix Scutellariae with subcritical water coupled to high performance liquid chromatographic analysis was established. The effects of various parameters, which included the pressure, temperature, extraction time, and the particle size of the plant material as well as the solvent/sample ratio on the yield were investigated. Compared to the conventional organic solvent extraction method, the subcritical water extraction method showed shorter handling time and lower solvent consumption without waste producing. The optimal conditions of extraction of baicalin from Radix Scutellariae with subcritical water were 0.15 - 0.18 mm particle size, solvent/sample ratio of 0.2 mL/mg, 5 MPa, 130 degrees C for about 10 min. This technique seems very promising for the extraction of liposoluble substances from plant materials.
Se pu = Chinese journal of chromatography / Zhongguo hua xue hui 02/2004; 22(1):44-7.
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ABSTRACT: To further understand the mechanic properties of the Intestinal Epithelial cells (IEC).
The viscoelastic properties of the IEC-6 were determined by micropipette aspiration.
The elastic coefficient K1 was 436.21 +/- 89.64 dyn/cm2 and K2 was 298.37 +/- 75.16 dyn/cm2. The visous coefficient micro was 15.94 +/- 4.93 dyn/(sec x cm2).
The elastic component reflects the degree of initial deformation of the IEC and makes a notable impact on the deformation of the IEC. The viscous component reflects the time dependency of the deformation of the IEC and influences the velocity of the IEC deformation.
Sichuan da xue xue bao. Yi xue ban = Journal of Sichuan University. Medical science edition 02/2003; 34(1):34-5, 39.
