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161.
A novel dispersive admicelle solid‐phase extraction method based on sodium dodecyl sulfate‐coated Fe3O4 nanoparticles was developed for the selective adsorption of berberine, coptisine, and palmatine in Gegen‐Qinlian oral liquid before high‐performance liquid chromatography. Fe3O4 nanoparticles were synthesized by a chemical coprecipitation method and characterized by using transmission electron microscopy. Under acidic conditions, the surface of Fe3O4 nanoparticles was coated with sodium dodecyl sulfate to form a nano‐sized admicelle magnetic sorbent. Owing to electrostatic interaction, the alkaloids were adsorbed onto the oppositely charged admicelle magnetic nanoparticles. The quick separation of the analyte‐adsorbed nanoparticles from the sample solution was performed by using Nd‐Fe‐B magnet. Best extraction efficiency was achieved under the following conditions: 800 μL Fe3O4 nanoparticles suspension (20 mg/mL), 150 μL sodium dodecyl sulfate solution (10 mg/mL), pH 2, and vortexing time 2 min for the extraction of alkaloids from 10 mL of diluted sample. Four hundred microliters of methanol was used to desorb the alkaloids by vortexing for 1 min. Satisfactory extraction recoveries were obtained in the range of 85.9–120.3%, relative standard deviations for intra‐ and interday precisions were less than 6.3 and 10.0%, respectively. Finally, the established method was successfully applied to analyze the alkaloids in two batches of Gegen‐Qinlian oral liquids.  相似文献   
162.
Suan‐Zao‐Ren granule is widely used to treat insomnia in China. However, because of the complexity and diversity of the chemical compositions in traditional Chinese medicine formula, the comprehensive analysis of constituents in vitro and in vivo is rather difficult. In our study, an ultra high performance liquid chromatography with quadrupole time‐of‐flight mass spectrometry and the PeakView® software, which uses multiple data processing approaches including product ion filter, neutral loss filter, and mass defect filter, method was developed to characterize the ingredients and rat serum metabolites in Suan‐Zao‐Ren granule. A total of 101 constituents were detected in vitro. Under the same analysis conditions, 68 constituents were characterized in rat serum, including 35 prototype components and 33 metabolites. The metabolic pathways of main components were also illustrated. Among them, the metabolic pathways of timosaponin AI were firstly revealed. The bioactive compounds mainly underwent the phase I metabolic pathways including hydroxylation, oxidation, hydrolysis, and phase II metabolic pathways including sulfate conjugation, glucuronide conjugation, cysteine conjugation, acetycysteine conjugation, and glutathione conjugation. In conclusion, our results showed that this analysis approach was extremely useful for the in‐depth pharmacological research of Suan‐Zao‐Ren granule and provided a chemical basis for its rational.  相似文献   
163.
A novel averagely linear‐quantified fingerprint method was proposed and successfully applied to monitor the quality consistency of alkaloids in powdered poppy capsule extractive. Averagely linear‐quantified fingerprint method provided accurate qualitative and quantitative similarities for chromatographic fingerprints of Chinese herbal medicines. The stability and operability of the averagely linear‐quantified fingerprint method were verified by the parameter r . The average linear qualitative similarity (improved based on conventional qualitative “Similarity”) was used as a qualitative criterion in the averagely linear‐quantified fingerprint method, and the average linear quantitative similarity was introduced as a quantitative one. was able to identify the difference in the content of all the chemical components. In addition, was found to be highly correlated to the contents of two alkaloid compounds (morphine and codeine). A simple flow injection analysis was developed for the determination of antioxidant capacity in Chinese Herbal Medicines, which was based on the scavenging of 2,2‐diphenyl‐1‐picrylhydrazyl radical by antioxidants. The fingerprint–efficacy relationship linking chromatographic fingerprints and antioxidant activities was investigated utilizing orthogonal projection to latent structures method, which provided important pharmacodynamic information for Chinese herbal medicines quality control. In summary, quantitative fingerprinting based on averagely linear‐quantified fingerprint method can be applied for monitoring the quality consistency of Chinese herbal medicines, and the constructed orthogonal projection to latent structures model is particularly suitable for investigating the fingerprint–efficacy relationship.  相似文献   
164.
Xiao‐Qing‐Long‐Tang is a traditional Chinese formula used for the treatment of cold syndrome, bronchitis, and nasal allergies for thousands of years. However, the in vivo integrated metabolism of its multiple components and the active chemical constituents of Xiao‐Qing‐Long‐Tang remain unknown. In this study, a method using ultra high performance liquid chromatography coupled with quadrupole time‐of‐flight tandem mass spectrometry was established for the detection and identification of the metabolites in human and rat urine after oral administration of Xiao‐Qing‐Long‐Tang. A total of 19 compounds were detected or tentatively identified in human urine samples, including eight prototypes and 11 metabolites. Also, a total of 50 compounds were detected or tentatively identified in rat urine samples, including 15 prototypes and 35 metabolites detected with either a highly sensitive extracted ion chromatogram method or the MSE determination using Mass Fragment software. Our results indicated that phase Ⅱ reactions (e.g. glucuronidation and sulfation) were the main metabolic pathways of flavones, while phase I reactions (e.g. demethylation and hydroxylation) were the major metabolic reaction for alkaloids, lignans, and ginger essential oil. This investigation provided important structural information on the metabolism of Xiao‐Qing‐Long‐Tang and provided evidence to obtain a more comprehensive metabolic profile.  相似文献   
165.
The extraction adsorbent was fabricated by immobilizing the highly specific recognition and binding of aptamer onto the surface of Fe3O4 magnetic nanoparticles, which not only acted as recognition elements to recognize and capture the target molecule berberine from the extract of Cortex phellodendri , but also could favor the rapid separation and purification of the bound berberine by using an external magnet. The developed solid‐phase extraction method in this work was useful for the selective extraction and determination of berberine in Cortex phellodendri extracts. Various conditions such as the amount of aptamer‐functionalized Fe3O4 magnetic nanoparticles, extraction time, temperature, pH value, Mg2+ concentration, elution time and solvent were optimized for the solid‐phase extraction of berberine. Under optimal conditions, the purity of berberine extracted from Cortex phellodendri was as high as 98.7% compared with that of 4.85% in the extract, indicating that aptamer‐functionalized Fe3O4 magnetic nanoparticles‐based solid‐phase extraction method was very effective for berberine enrichment and separation from a complex herb extract. The applicability and reliability of the developed solid‐phase extraction method were demonstrated by separating berberine from nine different concentrations of one Cortex phellodendri extract. The relative recoveries of the spiked solutions of all the samples were between 95.4 and 111.3%, with relative standard deviations ranging between 0.57 and 1.85%.  相似文献   
166.
Radix Sophorae flavescentis is generally used for the treatment of different stages of prostate cancer in China. It has ideal effects when combined with surgical treatment and chemotherapy. However, its active components are still ambiguous. We devised a comprehensive two‐dimensional PC‐3 prostate cancer cell membrane chromatography system for screening anti‐prostate cancer components in Radix Sophorae flavescentis . Gefitinib and dexamethasone were chosen as positive and negative drugs respectively for validation and optimization the selectivity and suitability of the comprehensive two‐dimensional chromatographic system. Five compounds, sophocarpine, matrine, oxymatrine, oxysophocarpine, and xanthohumol were found to have significant retention behaviors on the PC‐3 cell membrane chromatography and were unambiguously identified by time‐of‐flight mass spectrometry. Cell proliferation and apoptosis assays confirmed that all five compounds had anti‐prostate cancer effects. Matrine and xanthohumol had good inhibitory effects, with half maximal inhibitory concentration values of 0.893 and 0.137 mg/mL, respectively. Our comprehensive two‐dimensional PC‐3 prostate cancer cell membrane chromatographic system promotes the efficient recognition and rapid analysis of drug candidates, and it will be practical for the discovery of prostate cancer drugs from complex traditional Chinese medicines.  相似文献   
167.
Raw Arecae Semen, the seed of Areca catechu L., as well as Arecae Semen Tostum and Arecae semen carbonisata are traditionally processed by stir‐baking for subsequent use in a variety of clinical applications. These three Arecae semen types, important Chinese herbal drugs, have been used in China and other Asian countries for thousands of years. In this study, the sensory technologies of a colorimeter and sensitive validated high‐performance liquid chromatography with diode array detection were employed to discriminate raw Arecae semen and its processed drugs. The color parameters of the samples were determined by a colorimeter instrument CR‐410. Moreover, the fingerprints of the four alkaloids of arecaidine, guvacine, arecoline and guvacoline were surveyed by high‐performance liquid chromatography. Subsequently, Student's t test, the analysis of variance, fingerprint similarity analysis, hierarchical cluster analysis, principal component analysis, factor analysis and Pearson's correlation test were performed for final data analysis. The results obtained demonstrated a significant color change characteristic for components in raw Arecae semen and its processed drugs. Crude and processed Arecae semen could be determined based on colorimetry and high‐performance liquid chromatography with a diode array detector coupled with chemometrics methods for a comprehensive quality evaluation.  相似文献   
168.
We utilized ultra‐high performance liquid chromatography with tandem mass spectrometry and dispersive solid‐phase extraction to develop a new method for the detection of nine analytes (scopolamine, cephaeline, strychnine, hyoscyamine, brucine, hydrastine, ajmalicine, colchicine, and oleandrin) in herbal cosmetics. Acetonitrile/water and 2‐propylaminoethylamine were used to disperse and purify during the dispersive solid‐phase extraction step. The analytes were separated by a Waters UPLC HSS T3 column and detected through electrospray ionization source in the positive mode with multi‐reaction monitoring conditions. Under the optimal conditions, the calibration curves were linear in the range of 0.2–100.0 μg/L with the correlation coefficients higher than 0.995. The method limit of quantitation (S/N = 10) were 5.0 μg/kg for oleandrin and 1.0 μg/kg for the other eight alkaloids. The mean recoveries at three spiked concentration levels of 1.0–10.0 μg/kg were in the range of 86.9–116.5% with the intra‐day relative standard deviations (n  = 6) ranging from 2.4 to 8.8%, and inter‐day relative standard deviations ranging from 2.7 to 5.7%. This method is accurate, simple and rapid, and has been applied to the quality supervision of herbal cosmetics in Guangzhou.  相似文献   
169.
170.
The quality consistency of Yinqiaojiedu tablets (YQJDTs) was monitored by extracting their electrophoretic fingerprint and marker compound data that were obtained using capillary electrophoresis. To select the suitable background electrolyte, wing‐shape method was proposed. A background electrolyte composed of 103.1 mM boric acid, 51.6 mM sodium borate, 9.8 mM disodium hydrogen phosphate, and 15.6 mM sodium dihydrogen phosphate was used to separate compounds. Under the optimized conditions, the content of three marker compounds was determined in 25 YQJDT samples. The capillary electrophoresis fingerprints were developed simultaneously, then 25 samples from two manufacturers were clearly divided into two clusters based on the principal component analysis. In fingerprint assessments, systematic quantified fingerprint method was adopted for integrative quality discrimination of YQJDTs from both qualitative and quantitative perspectives, by which the qualities of 25 samples were well differentiated. In addition, partial least squares model was established to explore fingerprint–efficacy relationship between the fingerprints and the antioxidant activities in vitro, providing clinically useful information for quality control. The proposed method was reliable and comprehensive, which could be used for a valuable reference to monitor the quality consistency of traditional Chinese medicines.  相似文献   
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