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101.
102.
Characterization of chemical constituents and rats metabolites of Shuanghua Baihe tablets by HPLC‐Q‐TOF‐MS/MS 下载免费PDF全文
Lu Zheng Haijian Cong Ming Xue Ting Xiang Zhongqing Yao Bin Wu Wenhui Lin 《Biomedical chromatography : BMC》2015,29(1):75-86
A high‐performance liquid chromatography/quadrupole time‐of‐flight mass spectrometry method was established to detect as many constituents in rat biological fluids as possible after oral administration of Shuanghua Baihe tablets (SBT). An Agilent Poroshell 120 EC‐C18 column was adopted to separate the samples, and mass spectra were acquired in positive and negative modes. First, the fingerprints of SBT were established, resulting in 32 components being detected within 40 min. Among these compounds, 12 were tentatively identified by comparing the retention times and mass spectral data with those of reference standards and the reference literature; the other 20 components were tentatively assigned solely based on the MS data. Furthermore, metabolites in rat plasma and urine after oral administration of SBT were also analyzed. A total of 19 compounds were identified, including 13 prototypes and six metabolites through metabolic pathways of demethylation and glucuronide conjugation. Glucuronidated alkaloids were the main constituents in the plasma, and were then excreted from urine. This is the first systematic study on the metabolic profiling of SBT. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
103.
《Analytical letters》2012,45(12):925-939
Abstract Anodic stripping voltammetry is applied for measurement of copper and zinc in pharamaceutical formulations. Because of the inherent sensitivity and selectivity of stripping voltammetry toward amalgam forming metals, no sample preparation is required (except for acidic dissolution). Copper-zinc intermetallic interferences are eliminated by the addition of an excess of gallium or through utilization of a dual working electrode approach. Automation of this procedure is indicated from flow injection measurments at a rate of 15 per hour. 相似文献
104.
《Analytical letters》2012,45(18):2951-2961
Abstract An isocratic HPLC method was developed and validated for the simultaneous determination of ibuprofen (IBU) and pseudoephedrine hydrochloride (PSE). Chromatography was carried out on an Apex phenyl column using 0.025 M acetic acid, triethylamine solution (pH 4.5) – acetonitrile (80:20, v/v) as mobile phase at a flow rate of 1 mL · min?1. UV detection was performed at a wavelength of 210 nm. The method was validated for specificity, linearity, accuracy, precision, and was successfully applied to pharmaceutical tablets of Rhinadvil®. 相似文献
105.
《Analytical letters》2012,45(14):2521-2534
Abstract In this study, simultaneous determination of caffeine and meclizine dihydrochloride in their binary mixture was conducted by two spectrophotometric methods. In the first method, derivative spectrophotometry, the quantification of caffeine and meclizine dihydrochloride was performed by reading the dA/dλ values at 286.2 nm and 243.4 nm respectively in the first derivative spectra of their mixture in methanol. The relative standard deviation of the method was 0.54% for caffeine and 0.67% for meclizine dihydrochloride. In the second, selective precipitation + derivative spectrophotometry, determination of meclizine dihydrochloride was carried out by precipitation with potassium ferricyanide at pH 2 selectively, then measuring the absorbance of its solution in methanol at 420.8 nm, and determination of caffeine was succeeded by reading the dA/dλ values at 260.6 nm in the first derivative spectra of the remaining solution after precipitation. Relative standard deviation of the method was found to be 0.56% for caffeine and 1.85% for meclizine dihydrochloride. These two methods were applied successfully to a sugar-coated tablet containing these drugs. 相似文献
106.
《Analytical letters》2012,45(8):951-961
Abstract Carbamazepine, a tricyclic antidepressant, has been assayed in its tablets (Tegretol ®) by the application of PMR spectrometry. The proposed method involves comparing the integral of the aromatic and olefinic protons of carbamazepine, in the range 6.60 -7.60 ppm, to that of the singlet of a known amount of hexamethylcyclotrisilazane (at 0.00 ppm) used as internal standard. The method is simple, rapid and accurate. The average percent recovery, of carbamazepine from its tablets, is 96.88 ± 0.93. In addition, the PMR spectrum obtained helps in checking the identity and purity of the drug extracted from its pharmaceutical preparation. 相似文献
107.
《Analytical letters》2012,45(3):424-436
Abstract High‐performance liquid chromatographic (HPLC) and UV derivative spectrophotometric (UVDS) methods were developed and validated for the quantitative determination of nadolol in tablets. The HPLC method was performed on a C18 column with fluorescence detection. The excitation and emission wavelengths were 230 and 300 nm, respectively. A mobile phase composed by acetonitrile‐water containing 0.1% triethylamine (15∶85 v/v) and pH adjusted to 4.6 with formic acid was used. The UVDS method was performed taken a signal at 279.5 nm. The correlation coefficient (r) obtained for both methods was 0.9999. The proposed methods are simple, precise, accurate, and can be used in routine analysis. 相似文献
108.
PLS紫外分光光度法同时测定复方阿斯匹林三组分含量的研究 总被引:1,自引:0,他引:1
复方阿司匹林(APC)是常用的解热镇痛药物,片剂中乙酰水杨酸,咖啡因,非拉西丁的同时测定方法有线性最小二乘法[1],系数倍率法[2]等,由于APC三组分中咖啡因的含量相对较少往往使测定值有较大偏差。本文利用乙酰水杨酸易水解的性质,加入NaOH溶液使之完全水解为水杨酸钠间接求得乙酰水杨酸含量,同时在浓度校正及样品测定时适当增加咖啡因浓度而使各组分浓度差别减小,利用PLS法测定三组分含量。1 PLS法分析原理偏最小二乘法(PartialLeastSquares简称PLS)是一种多组分同时测定的新计算方法。与双波长分光光度法[3],线性规划法[4]比较,它… 相似文献
109.
小波变换近红外光谱结合径向基神经网络快速分析异福片 总被引:3,自引:0,他引:3
应用小波变换(WT)处理近红外漫反射光谱结合径向基神经网络(RBFNN)建立快速分析异福片中利福平和异烟肼含量的模型(WT-RBFNN)。用小波变换的低频系数作为RBFNN的输入节点, 研究了网络参 数包括隐含层神经元数和径向基宽度(SC)对模型的影响。与经典的RBFNN和PLS相比较表明, WT-RBFNN模型压缩了原始光谱, 除去了噪音和背景的影响, 拟合效果很好。优选的WT-RBFNN模型对校正集样品 中利福平、异烟肼的交互验证均方根误差(RMSECV)分别为0.006 04和0.004 57;对预测集样品预测均方根误差(RMSEP)分别为0.006 39和0.005 87。同时预测集样品中利福平和异烟肼与RP-HPLC测定结果 的回归系数(r)分别为0.995 22和0.993 92, 相对误差在2.300%以下。这些结果显示了该方法建模的稳健性和模型的预测精度均很高, 同时此方法具有非破坏、无污染、可在线检测等优点, 对替代常规药物 分析方法有重要的意义。 相似文献
110.
微波消解ICP-AES法测定牛黄解毒片中的微量元素 总被引:14,自引:2,他引:12
采用HNO3-H2O2消解体系对牛黄解毒片样品进行微波消解制样,利用ICP-AES法同时测定了牛黄解毒片中As,Ca,Mg,Al,Mn,Sr,Ba,Se,Ni,Cd,Cu,Zn,Mo和Pb等14种微量元素的含量,对样品的前处理条件进行了探讨,通过添加标准回收实验,验证了分析数据的可靠性。结果表明, 该方法快速、简便、数据准确可靠, 结果令人满意, 适合常规分析。 相似文献