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321.
不同溶剂在微波条件下对4种不同产地丹参进行快速提取,用紫外分光光度计对相同溶剂的提取物进行对比研究,发现其紫外光谱存在差异,可用于不同产地丹参的鉴别.  相似文献   
322.
Fast and sensitive monitoring of drug‐induced liver and kidney injury in early stage is beneficial. An ultrafast liquid chromatography with tandem mass spectrometry assay was developed and validated to simultaneously determine ten endogenous biomarkers in serum and urine, including hippuric acid, phenylacetylglycine, 5‐oxoproline, cholic acid, taurine, indoleacetic acid, 3‐indoxyl sulfate, guanidinosuccinic acid, guanidinoacetic acid and uric acid. A CAPCELL CORE PC column (2.1 × 150 mm, 2.7 μm) was adopted for analytes separation. Gradient elution was performed with acetonitrile and water containing 5 mM ammonium acetate. Simple protein precipitation was applied in sample preparation. Good linearities were achieved with all the regression coefficients above 0.9911. Accuracy was 2.9–14.2% in serum and 4.1–14.6% in urine. The mean recovery was above 70% with acceptable matrix effects. The method was applied to monitor injury induced by Euphorbiae pekinensis Radix with a subacute rats model. All the biomarkers showed obvious concentration changes during the injury period. Furthermore, several biomarkers showed significant changes in earlier stage when compared with the current clinical serum bio‐parameters. The method might be helpful for early diagnosis of drug induced liver and kidney injury in clinical after tested on more drugs.  相似文献   
323.
A high-performance liquid chromatographic (HPLC) method coupled with ultraviolet (UV) and electrospray ionization time-of-flight mass spectrometry (ESI-TOF/MS) was established for simultaneous qualitative and quantitative determination of nine phenolic acids and six diterpenoids in Radix et Rhizoma Salviae Miltiorrhizae (RRSM). The optimal chromatographic conditions were achieved on a Zorbax C(18) column by gradient elution with 0.1% (v/v) aqueous formic acid and acetonitrile as mobile phase at the flow rate of 1.0 mL/min. The detection wavelength at 281 nm was chosen to determine the 15 bioactive components, namely danshensu (1), protocatechuic acid (2), protocatechuic aldehyde (3), caffeic acid (4), rosmarinic acid (5), lithospermic acid (6), salvianolic acid B (7), salvianolic acid A (8), salvianolic acid C (9); dihydrotanshinone I (10), cryptotanshinone (11), tanshinone I (12), methylene tanshiqunone (13), tanshinone IIA (14) and miltirone (15). Additionally, LC-ESI-TOF/MS was used to make definite identification of the constituents in samples in comparison with those reference compounds. The validation of the method included tests of linearity, sensitivity, repeatability, stability and recovery. The proposed method was successfully applied to quantify the 15 components in 21 samples; significant variations were demonstrated in the contents of the samples from diverse species and origins. The developed method could be used to effectively and comprehensively evaluate the quality of RRSM for its clinical safety and efficacy.  相似文献   
324.
In order to determine isoflavone glycosides (calycosin‐7‐O‐β‐d ‐glucoside and formononetin‐7‐O‐β‐d ‐glucoside) and aglycones (calycosin and formononetin), a simple HPLC method with isocratic elution employing hydroxypropyl‐β‐cyclodextrin (HP‐β‐CD) as a mobile phase additive was developed. Various factors affecting the retention of isoflavone glycosides and aglycones in the C18 reversed‐phase column, such as the nature of cyclodextrins, HP‐β‐CD concentration, and methanol concentration, were systematically studied. The results show that HP‐β‐CD, as a very effective mobile phase additive, can markedly reduce the retention of isoflavone glycosides and aglycones, and the decrease magnitudes of isoflavone aglycones are more than those of their glycosides. The role of HP‐β‐CD in the developed HPLC method is attributed to the formation of the inclusion complexes between isoflavone glycosides (or aglycones) and HP‐β‐CD. So, the apparent formation constants of the isoflavone glycosides (or aglycones)/HP‐β‐CD inclusion complexes also were investigated. Isoflavone glycosides (and aglycones) form the 1:1 inclusion complexes with HP‐β‐CD, and the isoflavone aglycones/HP‐β‐CD complexes are more stable than the isoflavone glycosides/HP‐β‐CD complexes. Finally, the optimized method was successfully applied for the determination of isoflavone glycosides and aglycones in Radix Astragali samples.  相似文献   
325.
Angelicae Radix (AR) and Ligustici Rhizoma (LR) are both derived from the Umbelliferae plants and contain similar organic acids as their bioactive compounds. Nine of these organic acids, including nicotinic acid, protocatechuic acid, phthalic acid, folinic acid, p-hydroxybenzoic acid, folic acid, vanillic acid, caffeic acid, and ferulic acid were separated by HPLC and CE. Detection at 210 nm with a linear gradient containing 20 mM KH2PO4 (pH 3.5) and H2O-CH3CN in HPLC and with a buffer solution containing 10 mM LTAC, 2 mM Na2HPO4, 9 mM Na2B4O7(pH 9.56), and CH3CN in CE were found to be the most efficient eluents for this separation. The contents of the nine components in crude extracts of either AR or LR could easily be determined within 60 min by LC and within 20 min by CE. The structures of the individual peaks in the LC chromatogram were identified by LC-MS. The effects of buffers on the separation and validation of the two methods were examined.  相似文献   
326.
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   
327.
用原子吸收光谱法,对生地熟地中镁、铜、锌、铁、锰、镉、钴7种矿物元素进行了测定,发现生地与熟地中Fe的含量都很高,熟地的补血作用可能与Fe元素的存在形态发生变化有关,使更多的Fe^3+与血浆转铁蛋白结合。另外,AAS法具有良好的准确度和精确度,测定结果准确、可靠。测定结果可为以后生地、熟地中矿物元素与药效间的关系以及新药的开发、研制等奠定一定的理论基础。  相似文献   
328.
徐长卿中药中丹皮酚含量的测定   总被引:1,自引:0,他引:1  
采用紫外分光光度法测定了徐长卿中药中丹皮酚的含量。丹皮酚在1—8μg/mL具有良好的线性关系,徐长卿中丹皮酚含量为0.9676%,平均加标回收率为101.21%。该方法简便、快捷、准确、重现性好,可作为检测徐长卿中丹皮酚含量的一种好方法。  相似文献   
329.
索建兰  袁佳妹 《光谱实验室》2012,29(3):1620-1623
探讨多因素实验条件对白芷的提取工艺参数的影响,以欧前胡素和异欧前胡素的含量为指标,以乙醇浓度、乙醇用量、提取时间、提取次数为因素进行单因素试验。结果表明,白芷的最佳提取工艺参数为:以8倍量80%乙醇提取3次,每次lh。  相似文献   
330.
山豆根和北豆根挥发性成分的对比分析   总被引:5,自引:1,他引:4  
采用GC-MS对山豆根和北豆根的挥发性化学成分进行了分析。通过谱图检索和解析,从山豆根中确定了35种挥发性成分,从北豆根中确定了31种。其中北豆根中的化合物类型较多,含氮化合物和含氧杂环化合物明显较北豆根多。两种中草药中量最多的都是脂肪酸,但山豆根为十八碳二烯酸、十六碳酸和六碳酸;北豆根为十三碳烯酸。  相似文献   
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