Electrophoretic behavior study and determination of some active components in Chinese medicinal preparations by capillary electrophoresis

Chemical comparison of two dosage forms of Hemp Seed Pills by UHPLC-Q-ToF-MS/MS and multivariate statistical techniques

Hemp seed soft gel capsule (HSSGC) is a modernised dosage form that is derived from a traditional Chinese patent medicine, Hemp Seed Pills (HSP). Two dosage forms claim the same therapeutic effects; however, their chemical components and chemical equivalency are unclear. In the present study, an ultra performance liquid chromatography coupled with time-of-flight mass spectrometry (UHPLC-ToF-MS)-based chemical profiling approach was proposed to rapidly evaluate the chemical differences between HSP and HSSGC as model dosage forms. Samples of the two dosage forms were subjected to UHPLC-ToF-MS analysis. The datasets of retention time (TR) and mass-to-charge ratio (m/z) pairs, ion intensities and sample codes were processed with principal component analysis (PCA) and partial least squares discriminate analysis (PLS-DA) to holistically compare the difference between these two dosage form samples. A clear classification trend was observed in the score plot, and a loading bi-plot was generated in which the variables are correlated with the group and the samples that were observed. The important chemical components that caused differences among the samples were explored with a Variables Importance Projection (VIP) index. Using the proposed approach, global chemical differences were found between the two dosage forms and among samples of the same dosage form. The most important components that are related to the differences were identified and most of them were attributed to Fructus Aurantii Immaturus. It is suggested that this newly established approach could be used for pre-clinical trial chemical equivalence study or the quality evaluation of the traditional medicinal products with large variations in quality.

Determination of active components in Chinese medicinal preparations by capillary electrophoresis

The determination of paeoniforin, paeonol, and censenoside Rg1 in traditional Chinese medicinal preparations, Tze Po San Pien pills and Liuwen Dihuang pills has been investigated by micellar electrokinetic capillary electrophoresis with borate buffer (20 mM), sodium dodecylsulfate (30 mM) and acetonitrile (20%) as background electrolytes (pH 9.30), 20 kV applied voltage and 203 nm UV detection. The effects of SDS concentration, borate, buffer pH, and organic modifier on electrophoretic behavior and separation are discussed. Regression equations revealed linear relationships between the peak-area of each component and the content with the correlation coefficients from 0.9982 to 0.9999. In addition, the levels of the active compounds in two kinds of traditional Chinese medicinal preparations were easily determined with the recoveries from 93.1% to 108.2%.

Determination of icariin and metabolites in rat serum by capillary zone electrophoresis: rat pharmacokinetic studies after administration of icariin

A simple and rapid method for determination of icariin (ICA) and its two metabolites, icaritin (ICT) and desmethylicaritin (DICT), by capillary zone electrophoresis has been developed and validated. Optimum separation of ICA, ICT, and DICT was obtained on 43.6 cm x 50 microm capillary using sodium tetraborate (30 mmol/L), monobasic sodium phosphate (50 mmol/L)-acetonitrile (50:50, v/v) (pH 10.0) as running buffer. Carbamazepine (CMP) was used as internal standard (IS). The temperature and voltage were optimized at 25 degrees C and 12 kV, respectively. The limit of detection of ICA was 1.0 mg/L (S/N = 3) by UV detection at 270 nm. The elaborated method was tested in vivo after administration of a single dose of 120 mg ICA/kg to healthy rats. Calculated parameters confirmed usefulness of the method in rat pharmacokinetic studies on ICA.

Simultaneous determination of some active ingredients in anti-viral preparations of traditional Chinese medicine by micellar electrokinetic chromatography

A simple and rapid micellar electrokinetic chromatography method was developed for the simultaneous determination of quercetin, gentiopicrin, forsythin, chlorogenic acid and caffeic acid in anti-viral preparations of traditional Chinese medicine (apTCM). In this method, the effects of buffer pH, concentration of the borax and SDS, organic modifiers, applied voltage and temperature on the separation were tested and discussed. The results showed that the fi ve analytes could be well separated within 11 min under conditions of 40 mM borax (pH 9.65) containing 20 mM SDS, 20 kV, at 25 degrees C. In the tested concentration range, regression equations revealed good linear relationships (correlation coefficients 0.9920-0.9991) between the peak areas and corresponding concentrations. In addition, a multiple linear regression QSPR model was constructed to predict the migration times of the analytes and the results were satisfactory. The method was validated by analysis of the five compounds in three representative apTCM samples with recoveries ranging from 89.2 to 106.6%.

Simultaneous determination of gallic acid, albiflorin, paeoniflorin, ferulic acid and benzoic acid in Si–Wu decoction by high-performance liquid chromatography DAD method

A high-performance liquid chromatographic method was applied to the determination of gallic acid, albiflorin, paeoniflorin, ferulic acid and benzoic acid in Si-Wu decoction and other 13 combinations of the formula. These five compounds were analyzed simultaneously with a Zorbox SB C-18 column by gradient elution using 0.01% (v/v) phosphoric acid-acetonitrile as the mobile phase. The flow rate was 1 ml min(-1), and detection was set at 230 nm. The recovery of the method was in the range of 94.8-103.1%, and all the compounds showed good linearity (r>0.9995) in a relatively wide concentration range. The result indicated that the content of these five compounds changed after decocting process. The contents of paeoniflorin, albiflorin, ferulic acid and gallic acid increased and that of benzoic acid decreased significantly.

SPE-HPLC method for the determination and pharmacokinetic studies on paeoniflorin in rat serum after oral administration of traditional Chinese medicinal preparation Guan-Xin-Er-Hao decoction

A new HPLC method for the determination of paeoniflorin in rat serum with solid-phase extraction (SPE) for preconcentration is introduced. Paeoniflorin and an internal standard (pentoxifylline) were extracted from serum by means of SPE using cartridges with octadecyl chemically bound phase. The HPLC separation was then performed on a reversed-phase C(18) column using acetonitrile-water (18:82, v/v) as eluting solvent system, and UV detection at 230 nm to measure the analyte with a limit of quantitation about 10 ng ml(-1). The calibration curve for paeoniflorin was linear (r=0.9938) in the concentration range of 10-1200 ng ml(-1), both intra- and inter-day precision of the paeoniflorin were determined and their coefficience of variation did not exceed 10%. The validated method has been successfully applied for pharmacokinetic studies of paeoniflorin from rat serum after oral administration of Guan-Xin-Er-Hao decoction.

Capillary electrophoresis with field-enhanced stacking for rapid and sensitive determination of strychnine and brucine

A new capillary electrophoresis procedure with field-enhanced stacking concentration for the analysis of strychnine and brucine is established. After optimization of the separation and concentration conditions, the two alkaloids can be separated within 5 min and quantified with high sensitivity (The detection limits were 1.0 ng mL(-1) for strychnine and 1.4 ng mL(-1) for brucine). The method was useful for qualitative and quantitative analysis of strychnine and brucine in Strychnos nux-vomica L with recovery of 105.1% for strychnine and 98.4% for brucine.