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Summary

Yanghuo Sanqi tablet (YST), combined prescription mainly derived from the leaves of herba epimedii and the roots of Panax notoginseng, is a traditional Chinese medicine (TCM). Flavonoids (icarrin, epimedin A, epimedin B, epimedin C, and baohuoside I) and saponins (notoginsenoside R1, ginsenoside Rgl, and ginsenoside Rbl) are considered as the main bioactive compounds of YST. However, there is no report on quality control of TCMs by simultaneous determination of above-mentioned flavonoids and saponins so far. In this work, for the first time, a high-performance liquid chromatography-diode array detector-evaporative light-scattering detector (HPLC-DAD-ELSD) method was developed to evaluate the quality of YST through a simultaneous determination of five major active flavonoids and three main saponins. Optimum separations were obtained with a Zorbax SB-C18 column by gradient elution with acetonitrile-water as the mobile phase. The drift tube temperature of ELSD was set at 105 °C, and the nebulizing gas flow rate was 2.5 L min−1. The fully validated method was successfully applied to quantify the eight bioactive components in three lot products. This simple, low-cost, and reliable HPLC-DAD-ELSD method provided a new basis for assessing the quality of traditional Chinese medicinal compound preparations (TCMCPs) consisting of many bioactive components.

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Summary

Yanghuo Sanqi tablet (YST), combined prescription mainly derived from the leaves of Herba epimedii and the roots of Panax notoginseng, is a traditional Chinese medicine (TCM). Flavonoids (icarrin, epimedin A, epimedin B, epimedin C, and baohuoside I) and saponins (notoginsenoside R1, ginsenoside Rgl, and ginsenoside Rbl) are considered as the main bioactive compounds of YST. However, there is no report on quality control of TCMs by simultaneous determination of above-mentioned flavonoids and saponins so far. In this work, for the first time, a high-performance liquid chromatography-diode array detector-evaporative light scattering detector (HPLC-DAD-ELSD) method was developed to evaluate the quality of YST through a simultaneous determination of five major active flavonoids and three main saponins. Optimum separations were obtained with a Zorbax SB-C18 column by gradient elution with acetonitrile-water as the mobile phase. The drift tube temperature of ELSD was set at 105 °C, and the nebulizing gas flow rate was 2.5 L min−1. The fully validated method was successfully applied to quantify the eight bioactive components in three lot products. This simple, low-cost, and reliable HPLC-DAD-ELSD method provided a new basis for assessing the quality of traditional Chinese medicinal compound preparations (TCMCPs) consisting of many bioactive components.

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Summary

A rapid, simple, and practical high-performance liquid chromatographic method (HPLC) was developed and validated for the simultaneous determination of norephedrine (NME), norpseudoephedrine (NMP), ephedrine (E), pseudoephedrine (PE), and methylephedrine (ME) in traditional Chinese medicines (TCM) which contained Ephedrae Herba (Ephedra). This analysis could be accomplished within 12.5 min with an Alltima Phenyl Column by isocratic elution using a mixture of KH2PO4 (20 mM)-acetonitrile (96:4, v/v) as the mobile phase at a flow-rate of 0.6 mL min−1 and a wavelength of 210 nm. This method was successfully applied to quantify ephedra alkaloids in both Ma-xing-gan-shi decoction and Ephedra decoction. The concentration of total ephedra alkaloids (4.62 mg mL−1) in Ma-xing-gan-shi decoction was much lower than that (7.10 mg mL−1) in Ephedra decoction. Furthermore, the concentration of NME, NMP, E, PE, and ME was significantly lower in Ma-xing-gan-shi decoction than that in Ephedra decoction, respectively. The method was easily acceptable and would be popular with most analytical laboratories.

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Summary

1,7-Dihydroxy-3,8-dimethoxyxanthone (X1) and 1,8-dihydroxy-3,7-dimethoxyxanthone (X2) are two important xanthones of the Tibetan medicinal plant Gentianopsis paludosa (Hook. f.) Ma. They are very similar in structure, the only difference being exchange of OH and OCH3 at the 7 and 8 positions. By calculations based on the geometry of the molecules using the MM+ force field, the different distances between the hydroxyl groups of the two xanthones were obtained (4.64774 Å for X2 and 7.19412 Å for X1), therefore, the two hydroxyl groups of X1 should freely interact with more water molecules than those of X2 in aqueous solution. In other words, X2 is more hydrophobic than X1. Micellar electrokinetic capillary chromatography (MEKC) was therefore chosen for separation of the compounds. The optimum separation conditions were: 20 mm borate + 20 mm SDS (pH 9.8) as running buffer, 17.5 kV applied potential, and detection wavelength 260 nm. The two xanthones were well separated in 9.0 min, with Gaussian peak shapes. The repeatability of the MEKC method (expressed as RSD) for X1 and X2 was 0.9 and 1.1%, respectively, for migration time, and 3.1 and 1.4% for peak area. The limits of detection (S/N = 3) were 0.41 μg mL−1 for X1 and 0.82 μg mL−1 for X2. The recovery of the MEKC method for the two xanthones was also satisfactory.

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A simple and rapid HPLC method using a photodiode array (PDA) detector for the analysis of 3-hydroxycarboplatin and its related complex has been established for the first time. Separation of 3-hydroxycarboplatin and 3-hydroxy-1,1-cyclobutanedicarboxylic acid (3-HO-cbdca) was carried out on a Phenomenex ODS3 column using an aqueous solution containing 50 mM ammonium acetate and 5 mM sodium 1-octanesulfonate as the mobile phase. The flow rate was 0.8 mL min−1, the column temperature was 40°C, and the detection wavelength was 230 nm for 3-hydroxycarboplatin and 220 nm for 3-HO-cbdca. Different analytical performance parameters such as precision, accuracy, linearity, stability of the solution, specificity, limit of detection (LOD), limit of quantification (LOQ), and system suitability were determined using the Empower 2 software. The calibration curve of standard 3-hydroxycarboplatin showed good linearity (r = 0.9995) within the range 0.5–1.4 mg mL−1. The method was accurate and precise, with an average accuracy of 100.4% (RSD = 1.53%, n = 9), and the results of the system suitability test showed symmetrical peaks, good resolution (R s), and repeatability. It can be applied to the quality control of 3-hydroxycarboplatin.

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Bee pollen is a health food with a wide range of nutritional and therapeutic properties. However, the bioactive compounds of bee pollen have not been extensively revealed due to low efficacy in separation. High-speed counter-current chromatography (HSCCC) and solvent extraction were applied to separate tyrosinase inhibitors from camellia pollen in this study. The camellia pollen extracts prepared with petroleum ether, ethyl acetate, and n-BuOH have tyrosinase inhibitory activity. Acidic hydrolysis could promote the tyrosinase inhibitory activity of crude sample. Three fractions with tyrosinase inhibitory activity were separated from the hydrolysate by a one-step HSCCC procedure. Among the fractions, two chemicals were sufficiently purified and identified to be levulinic acid (LA) and 5-hydroxymethylfurfural (5-HMF). The recovery was 0.80 g kg−1 pollen for LA and 1.75 g kg−1 pollen for 5-HMF; and their purity was all over 98%. The study demonstrates that HSCCC method is powerful for preparative separation of tyrosinase inhibitors from camellia pollen.

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A rapid and sensitive method for the identification and quantification of phillyrin (POG) in Forsythia suspense is described. The phillyrin standard solution was directly infused into the ion trap mass spectrometers (IT-MS) for collecting the MSn spectra. The electrospray ionization (ESI) mass spectral fragmentation pathway of phillyrin was proposed, and the ESI-MSn fragmentation behavior of phillyrin was deduced in detail. The major product ion at m/z 355 belongs to furofuran, which was formed by loss the glucopyranoside (180 Da), and the characteristic fragment ions m/z 473, 395, 337, 309, and 249 were observed. The loss of 18 Da could arise from two different fragmentation pathways, and the observed ion was composed of a mixture of two different structural ions. Quantification of phillyrin was assigned in positive-ion mode at a product ion at m/z 557 → 355 by liquid chromatography-mass spectrometry (LC-MS). The LC-MS method was validated for linearity, sensitivity, accuracy, and precision and then used to determine the content of the phillyrin. Lastly, the LC-MS method was successfully applied to determine phillyrin in real sample F. suspense and three of its medicinal preparations in the positive mode at the first time.

Open access

Summary

A rapid and sensitive method for the identification and quantification of yohimbine in Pausinystalia yohimbe is described. The method used is liquid chromatography-quadrupole ion trap mass spectrometry (LC-QIT/MS). The yohimbine standard solution was directly infused into the ion trap mass spectrometers (IT/MS) for collecting the MSn spectra. The major fragment ions of yohimbine were confirmed by MSn at m/z 355, 224, 212, and 144, in the positive-ion mode. The possible main fragment ion cleavage pathway was studied. Yohimbine provided good signals corresponding to the protonated molecular ion [M + H]+. The method is reliable and reproducible, and the detection limit is 0.1 ng mL-1. The method was validated in the concentration range 0.1–50 μg mL−1; the intra- and interday precision ranged from 1.36% to 2.73% and the accuracy was 96.5–108.2%. The mean recovery of yohimbine was 97.1–101% with a relative standard deviation (RSD) <1.93%. The LC-IT/MS method was successfully applied to determine the yohimbine in P. yohimbe.

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This study aims to develop and validate a high-performance size-exclusion chromatography (HPSEC) method to determine the amount of polymer in cefmetazole sodium for injection and to compare this method with gel chromatography. A Zenix SEC-150 column was used with the mobile phase of phosphate buffer solution (pH 7.0; 0.01 M)—acetonitrile (90:10 v/v) at a flow rate of 0.8 mL min−1 and a detection wavelength of 240 nm. The polymer was quantified by an external standard method with self-control, and the amount was expressed by the percentage of cefmetazole. The HPSEC method was validated for specificity, linearity, and precision. The chromatographic conditions, chromatographic performances, sensitivity, linearity, and precision of the developed HPSEC method and gel chromatography were compared, and both methods were subsequently used to determine the amount of polymer from seven batches of samples. The HPSEC method was fully validated. The time of isocratic elution for sample assay was less than 14 min. The results of comparison indicate that the developed HPSEC method was superior to gel chromatography. The Student t test results also showed significant difference in the amount of polymer from the samples obtained by the two methods. Thus, the HPSEC method with two obvious advantages, the superior sensitivity and a shorter analysis time, is more suitable for determination of polymer amount in cefmetazole sodium for injection to control the quality of the product.

Open access