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151.
152.
In this article, a novel method termed as temperature-assisted ionic liquid dispersive liquid-liquid microextraction (TA IL-DLLME) combining high performance liquid chromatography with diode array detection (HPLC-DAD) was developed for the determination of anthraquinones in Radix et Rhizoma Rhei samples. The ionic liquid (1-hexyl-3-methylimidazolium hexafluorophosphate) was used to replace volatile organic solvent as an extraction solvent for the extraction of anthraquinones (aloe-emodin, rhein, emodin, chrysophanol and physcion) from Radix et Rhizoma Rhei. Several important parameters influencing the extraction efficiency of TA IL-DLLME such as the type and volume of extraction solvent and disperser solvent, sample pH, extraction time, extraction temperature, centrifugation time as well as salting-out effects were optimized. Under the optimal conditions, the spiked recovery for each analyte was in the range of 95.2-108.5%. The precisions of the proposed method were varied from 1.1% to 4.4% (RSD). All the analytes exhibited good linearity with correlation coefficients (r2) ranging from 0.9986 to 0.9996. The limits of detection for all target analytes were ranged from 0.50 to 2.02 μg L−1 (S/N = 3). The experimental results indicated that the proposed method was successfully applied to the analysis of anthraquinones in Radix et Rhizoma Rhei. 相似文献
153.
反向流动注射化学发光法测定姜黄素 总被引:2,自引:0,他引:2
铁氰化钾氧化鲁米诺在碱性介质中产生化学发光,姜黄素对该体系化学发光具有强烈的抑制作用。因此,利用该化学发光的抑制体系,结合反向流动注射技术,建立了测定大黄类药物姜黄素含量的新方法。在优化的条件下,化学发光抑制信号强度ΔI与姜黄素的浓度分别在1×10-7~1×10-6和1×10-6~1×10-5mol/L范围内呈良好的线性关系,检出限为1×10-9mol/L。对2.0×10-6mol/L的姜黄素进行平行测定10次,得相对标准偏差(RSD)为1.8%。方法应用于中药姜黄中姜黄素(总姜黄素计)的含量测定。 相似文献
154.
Chemical differentiation of volatile compounds in crude and processed Atractylodis Macrocephalae Rhizoma by using comprehensive two‐dimensional gas chromatography with time‐of‐flight mass spectrometry combined with multivariate data analysis 下载免费PDF全文
Gang Cao Hao Cai Jianping Jiang Linjiang Yao Sicong Tu Lin Wang Xiaoqing Ma Baochang Cai 《Journal of separation science》2014,37(9-10):1194-1198
In the present study, comprehensive 2D GC—TOF‐MS combined with multivariate data analysis was applied to analyze the differences of the volatile components in crude and processed Atractylodis Macrocephalae Rhizoma (AMR) samples. As a result, 26 compounds that were found in crude AMR samples disappeared in processed AMR samples, and 19 compounds were newly generated and identified in AMR after processing with wheat bran. Meanwhile, principal component analysis demonstrated that there were significant chemical differences between crude and processed AMR samples, and processing procedure caused obvious quantitative and qualitative changes of volatile components in AMR. The established method could be used to explain the chemical differentiation between crude and processed AMR, and to further understand the processing mechanism of herbal medicines. 相似文献
155.
Li‐Hong Ye Xi‐De Liu Jun Cao Mingrui An Shu‐Ling Wang Jing‐Jing Xu Li‐Qing Peng 《Electrophoresis》2016,37(23-24):3118-3125
A simple, efficient, and green chitosan‐assisted liquid–solid extraction method was developed for the sample preparation of isoquinoline derivative alkaloids followed by microemulsion LC. The optimized mobile phase consisted of 0.8% w/v of ethyl acetate, 1.0% w/v of SDS, 8.0% w/v of n‐butanol, 0.1% v/v acetic acid, and 10% v/v ACN. Compared to pharmacopoeia method and organic solvent extraction, this new approach avoided the use of volatile organic solvents, replacing them with relatively small amounts of chitosan. Under the optimum conditions, good linearity (r2 > 0.9980) for all calibration curves and low detection limits between 0.05 and 0.10 μg/mL were achieved. The presented procedure was successfully applied to determine alkaloids in Rhizoma coptidis with satisfactory recoveries (81.3–106.4%). 相似文献
156.
红外光谱法无损鉴别升麻的研究 总被引:22,自引:2,他引:22
本文利用傅里叶变换红外光谱法和计算机比对软件,快速、直接地测定了15种升麻基源植物,结果表明:各种升麻药村的基源植物由于其化学成分的不同以及各成分间的相对含量的不同,使每种样品都有自己独特的红外谱图。不同科的升麻样品谱图差别较显著;同属不同种的升麻谱图差别较大;同种不同产地、同种同产地不同采集时间的升麻谱图差别较小。该方法具有快速、准确、制样简单不需对样品进行提取分离、保持原性质等特点。 相似文献
157.
《Arabian Journal of Chemistry》2023,16(1):104417
Gualou-Xiebai-Banxia decoction (GXB) is a famous classical traditional Chinese medicine (TCM) formula for the treatment of coronary heart disease (CHD, namely chest stuffiness and pain syndrome in Chinese medicine). Compared with Gualou-Xiebai-Baijiu decoction, which only consists of Trichosanthis Pericarpium (TP), Allii Macrostemonis Bulbus (AMB) and wine, GXB comprises one additional herbal medicine, Pinellinae Rhizoma Praeparatum (PRP). However, due to a lack of kinetic profile studies on GXB, its in vivo components with high exposure remain unknown, making it difficult to interpret bioactive components likely linked to its efficacy, but also fails to provide substance-related evidence for reflecting the compatibility in GXB. The goal of this study was to systematically characterize the kinetic features of GXB in rat plasma and intestine content for revealing its in vivo high-exposure components on the basis of their metabolic fates, and to compare the kinetic differences between GXB and GXB-dePRP (GXB deducted PRP) for describing the chemical contribution of PRP to the compatibility in GXB. Firstly, the metabolic profile of GXB was systematically investigated by UPLC-Q/TOF-MS. Subsequently, quantitative methods for representative xenobiotics in rat plasma and intestine content were respectively validated and developed by UPLC-TQ-MS. Then, the established approaches were successfully applied to characterize the kinetic features of GXB through estimating pharmacokinetic parameters. These results showed that only a few kinds of xenobiotics at low exposure levels were observed in plasma, while various xenobiotics possessed high exposure in intestine content. Among them, steroidal saponins and triterpenoid saponins displayed relatively high exposure in plasma and intestine content, which are likely associated with the therapeutic effects of GXB. Moreover, there were no significant differences between metabolic profiles of GXB and GXB-dePRP, whereas the pharmacokinetic parameters, including area under the concentration–time curve (AUC) and Cmax (p < 0.05) for most xenobiotics in GXB were significantly larger than those in GXB-dePRP, implying that the introduction of PRP improved the bioavailability of constituents from TP and AMB. Altogether, this study laid a solid foundation and provided theoretical guidance for further clarification of bioactive components of GXB, as well as the synergistic effect of PRP to the compatibility in GXB. 相似文献