流动注射-化学发光法测定扑热息痛

基于在0.5mol.L-1氢氧化钠介质中,扑热息痛对鲁米诺-过氧化氢体系的化学发光具有显著的抑制作用,提出了流动注射-化学发光法测定扑热息痛含量的方法。在优化的试验条件下,扑热息痛的化学发光强度与其质量浓度在4.5×10-5～1.5×10-2g.L-1范围内呈线性关系,方法的检出限(3σ)为9.0×10-7 g.L-1。此法用于扑热息痛片的分析,测得加标回收率在93.3%～106.7%之间,测定值的相对标准偏差(n=6)在2.6%～3.0%之间。     

偶合反应流动注射化学发光法测定扑热息痛

基于扑热息痛还原铬(Ⅵ)和铬(Ⅲ)催化鲁米诺-过氧化氢的化学发光,建立了氧化还原偶合反应流动注射化学发光法测定扑热息痛的新方法.方法线性范围为4.0×10-9～4.0×10-5mol/L,检出限为1.0×10-9 mol/L.对4.0×10-7 mol/L扑热息痛平行测定8次,其标准偏差为2.7%.已将该方法用于片剂中...     

扑热息痛片剂药品的近红外光谱法非破坏定量分析

现代近红外光谱分析技术将近红外光谱 (NIR)法同计算机科学和化学计量学结合 ,实现了对样品进行无损非破坏性定量分析 .该法具有速度快、操作简单及所需样品少等特点 ,能够实现样品分析的时间同步、地点同步及无损非破坏分析 .为实现生产过程中即时、在线的质量控制提供了新的手段[1 ] .本文应用人工神经网络 [2 ]与近红外漫反射光谱相结合对扑热息痛片剂药品进行了非破坏快速定量分析 .用扑热息痛片剂药品的近红外漫反射光谱数据、一阶导数光谱数据及二阶导数光谱数据分别建立了 ANN模型 ,预测未知样品 ,讨论了影响网络的因素 ,使用了新…     

流动注射化学发光法测定扑热息痛

研究发现在碱性条件下 ,扑热息痛对鲁米诺 -铁氰化钾体系发光反应具有强烈的抑制作用 ,据此建立了流动注射化学发光测定痕量扑热息痛的新方法。扑热息痛浓度在 4 .0× 1 0 - 5～1 .0× 1 0 - 3g L范围内与发光强度呈良好的线性关系 ;检出限 ( 3σ)为 2 .4× 1 0 - 6 g L。相对标准偏差 (C =8.0× 1 0 - 4 g L ,n =1 1 )为 2 .3 %。方法用于片剂中扑热息痛含量测定 ,结果与标准方法一致。讨论了此体系发光机理     

扑热息痛分子印迹聚合物应用于固相萃取的研究

以扑热息痛为印迹分子,丙烯酰胺为功能单体,乙二醇二甲基丙烯酸酯为交联剂合成了棒状的印迹聚合物;把其装于自制的固相萃取柱中,研究了以乙腈和水为溶剂时扑热息痛在柱上的保留行为;通过优化清洗、洗脱条件,使扑热息痛和与其具有相似结构的非那西丁、对叔丁基苯酚在柱上得到了很好的分离;同时也测定了治疗感冒的药物海王银得菲中扑热息痛的含量,其回收率可达94．3％．     

氧化石墨烯/铁氰化铈修饰玻碳电极同时测定扑热息痛和咖啡因

采用滴涂法和电沉积法制备了氧化石墨烯/铁氰化铈(CeFe(CN)6)纳米复合膜修饰玻碳电极。用扫描电镜对氧化石墨烯和氧化石墨烯/CeFe(CN)6纳米复合膜进行了表征。分别用循环伏安法和差分脉冲伏安法研究了扑热息痛和咖啡因在修饰电极上的电化学行为。结果表明,在0.1 mol/L醋酸盐缓冲溶液(pH5.0)中,扑热息痛和咖啡因在此修饰电极上具有良好的电化学行为,扑热息痛和咖啡因分别在1.0×10-7～6.0×10-5mol/L和1.0×10-6～1.3×10-4mol/L浓度范围内与电化学响应信号呈良好的线性关系,相关系数分别为0.990和0.992;信噪比为3时,扑热息痛和咖啡因检出限分别为5.0×10-8mol/L和5.2×10-7mol/L。将本方法用于人尿样品分析,回收率为96.1%～105.4%。     

新铜试剂分光光度法测定片剂中的对乙酰氨基酚含量及其反应机理的研究

使用分光光度法测定扑热息痛中主要化学成分对乙酰氨基酚的含量。结果表明:在0.04~8.00 mg·L-1范围内对乙酰氨基酚含量与吸光度(A)呈良好的线性关系,其线性方程:A=0.1210c+0.0261,相关系数r=0.9968。表观摩尔吸光系数为1.8×104 L·mol-1·cm-1,平均回收率为100.2%,相对标准偏差RSD为1.51%。该实验所用仪器简单,且操作方便、快速。用该方法测定扑热息痛片剂对乙酰氨基酚的含量,取得了较好的效果。     

扑热息痛分子印迹膜电化学传感器的制备

以邻苯二胺为功能单体,扑热息痛为模板,采用循环伏安法在玻碳电极表面电聚合形成邻苯二胺电聚合膜,经无水乙醇将模板分子洗脱,制得扑热息痛分子印迹膜电极.通过方波伏安法研究此印迹传感器的分析性能,建立了以K3[Fe(CN)6]为活性电子探针的间接分析法.实验表明,该传感器具有高选择性和灵敏度.在2.0×10-6 ～8.0×1...     

扑热息痛分子印迹聚合物膜选择性结合和渗透性质的研究

采用紫外光引发原位聚合的方法制备了具有支撑膜的扑热息痛分子印迹聚合物膜. 紫外分光光度法证明了模板分子与功能单体之间存在相互作用, 并据此选择了聚合反应时合适的溶剂. 用傅立叶红外光谱和扫描电镜分别测定了膜的结构和表面形貌. 渗透实验结果表明渗透时所用溶剂对渗透结果有重要影响. 合适的渗透溶剂可提高印迹膜对模板分子的渗透选择性.     

导数光谱多组分标定法对阿司匹林、扑热息痛及水杨酸的同时测定

采用导数光谱多组分标定法,根据中心合成设计建立标定集和预测集,将PLS和PCR应用于阿司匹林、扑热息痛及水杨酸混合物的零阶和一阶导数光谱,从而实现了混合物中各组分的同时测定.实验结果表明,阿司匹林、扑热息痛及水杨酸的吸收光谱严重重叠;由于各组分零交叉点重合,零交叉点比光谱-导数分光光度法无法同时测量混合物中各组分的含量...     

优化迭代目标转换因子分析法在多组分混合物红外光谱解析中的应用

优化迭代目标转换因子分析法在多组分混合物红外光谱解析中的应用何锡文,陈鼎,王永泰（南开大学化学系、中心实验室,天津,３００００７１）关键词因子分析,相关性,红外光谱因子分析是一种多元统计方法,用其解析多组分混合物的红外光谱已有报道［１,２］。迭代目标...     

Multivariate curve resolution combined with gas chromatography to enhance analytical separation in complex samples: A review

This review describes the major advantages and pitfalls of iterative and non-iterative multivariate curve resolution (MCR) methods combined with gas chromatography (GC) data using literature published since 2000 and highlighting the most important combinations of GC coupled to mass spectrometry (GC–MS) and comprehensive two-dimensional gas chromatography with flame ionization detection (GC × GC-FID) and coupled to mass spectrometry (GC × GC–MS). In addition, a brief summary of some pre-processing strategies will be discussed to correct common issues in GC, such as retention time shifts and baseline/background contributions. Additionally, algorithms such as evolving factor analysis (EFA), heuristic evolving latent projection (HELP), subwindow factor analysis (SFA), multivariate curve resolution-alternating least squares (MCR-ALS), positive matrix factorization (PMF), iterative target transformation factor analysis (ITTFA) and orthogonal projection resolution (OPR) will be described in this paper. Even more, examples of applications to food chemistry, lipidomics and medicinal chemistry, as well as in essential oil research, will be shown. Lastly, a brief illustration of the MCR method hierarchy will also be presented.     

迭代目标转换因子分析光度法同时测定钇和其它稀土合量

以三氯偶氮胂为显色剂，根据钇(Y^3 )与其它稀土组分的显色络合物吸收光谱差别较大的特点，提出应用迭代目标转换因子分析光度法同时测定钇和其它烯土合量的计算光度分析法，通过对不同组成的人工模拟样品和龙南稀土氧化物标准样中的钇和其它稀土合量的测定，取得了满意的结果。     

Time shift correction in second-order liquid chromatographic data with iterative target transformation factor analysis

When the generalized rank annihilation method (GRAM) is applied to liquid chromatographic data with diode-array detection, an important problem is the time shift of the peak of the analyte in the test sample. This problem leads to erroneous predictions. This time shift can be corrected if a time window is selected so that the chromatographic profile of the analyte in the test sample is trilinear with the peak of the analyte in the calibration sample. In this paper we present a new method to determine when this condition is met. This method is based on the curve resolution with iterative target transformation factor analysis (ITTFA). The calibration and test matrices are independently decomposed into profiles and spectra, and aligned before GRAM is applied. Here we study two situations: first, when the calibration matrix has one analyte and second, when it has two analytes. When the calibration matrix has two analytes, we selectively determine the time window for the analyte to be quantified. There were considerably fewer prediction errors after correction.     

Application of multivariate curve resolution methods to on-flow LC-NMR

The application of evolving window factor analysis (EFA), subwindow factor analysis (SFA), iterative target transformation factor analysis (ITTFA), alternating least squares (ALS), Gentle, automatic window factor analysis (AUTOWFA) and constrained key variable regression (CKVR) to resolve on-flow LC-NMR data of eight compounds into individual concentration and spectral profiles is described. CKVR has been reviewed critically and modifications are suggested to obtain improved results. A comparison is made between three single variable selection methods namely, orthogonal projection approach (OPA), simple-to-use interactive self-modelling mixture analysis approach (SIMPLISMA) and simplified Borgen method (SBM). It is demonstrated that LC-NMR data can be resolved if NMR peak cluster information is utilised.     

校正变换矩阵法及其在多组分直接同时测定中的应用

将目标变换因子分析中自由浮动技术引入多元校准中，提出了一种新的多组分同时校准法———校正变换矩阵法。该法用于四组分氨基酸人工混合样品分析，结果令人满意，通过与传统目标变换因子分析法比较研究，表明该法用于组分光谱严重共线的波长范围时，其校准能力大大优于传统目标变换法。     

计算机模拟研究目标转换因子分析分辨重迭溶出伏安峰

本文用计算机模拟研究目标转换因子分析分辨重迭溶出伏安峰．设计了两个计算机程序（ＳＰＧＲＥＬＥＰ）和（ＥＬＥＣＴＴＦＡ）用于伏安图模拟和目标转换因子分析，采用了伏安图全部信息和矩阵处理技术．ＥＬＥＣＴＴＦＡ程序用于确定组分数，验证组分种类和进行未知重迭溶出伏安图的定量分析．实验结果表明本方法是成功的，甚至对严重重迭溶出伏安图亦可奏效．     

Simultaneous polarographic analysis of pyrazine and its methyl derivatives by iterative target transformation factor analysis

The polarographic waves of pyrazine and its methyl derivatives are seriously overlapping, so they cannot be determined individually by polarographic methods without a prior separation. In this paper, a chemometric approach, iterative target transformation factor analysis (ITTFA), is developed and applied to the determination of mixtures of pyrazines at trace level (2.0–9.0 × 10⁻⁶moll⁻¹) by using differential pulse polarography (DPP) and a static mercury drop electrode (SMDE). Different from the general ITTFA method, only one-dimensional measurement data of n − 1 standards and an unknown were used in this work. It produced acceptable results with average recoveries in the 96–108% range and relative standard errors in the 3.4–9.5% range.     

Determination of orotic acid in urine by capillary zone electrophoresis in tandem-coupled columns with diode array detection

Analytical potentialities of capillary zone electrophoresis in the separation system with tandem-coupled columns to the spectral identification and determination of orotic acid (OA) in urine by diode array detection (DAD), coupled to the separation system via optical fibers, were investigated. A very significant “in-column” clean-up of OA from urine matrix was reached in the separation stage of the tandem by combining a low pH (2.8) with complexing effects of electroneutral agents [- and β-cyclodextrins, poly(vinylpyrrolidone) and 3-(N,N-dimethyldodecylammonio)propanesulfonate]. Due to this, its DAD spectral data could be acquired in the detection stage of the tandem with almost no disturbances by matrix co-migrants. The concentration limits of detection obtained under such working conditions for a 200-nl sample load of OA and 320 μm I.D. capillary tubes were 3.5 μmol/l (218 nm) and 0.4 μmol/l (280 nm). Using chemometry procedures (target transformation factor analysis, fixed size moving window-evolving factor analysis, orthogonal projection approach and fixed size moving window–target transformation factor analysis) in processing of the acquired spectral data, the presence of OA in the loaded urine matrix could be confirmed with confidence when its concentration was 10 μmol/l or slightly less.     

Resolving co-eluting chromatographic patterns by means of dissimilarity analysis in iterative target transformation factor analysis

The initialization of concentration vector for iterative target transformation factor analysis (ITTFA) and identification of pure or key variables are the important issue in MCR. In this study, dissimilarity analysis and evolving factor analysis (EFA) are combined to find the selective or key variables and subsequently obtain initial estimates of the concentration vectors for resolution of gas chromatography/mass spectrometry (GC/MS) data by ITTFA. For systems containing components with highly similar mass spectra, a new constraint setting the elements out of elution window to 0 is used to improve convergence rate and accuracy of results. Tested by standard mixture of two wax esters and real GC/MS data of gasoline 97#, dissimilarity based ITTFA could obtain accurate results (average Dot product of concentration vectors, average deviation of peak area ratio and average similarity of mass spectra are 0.9929, 0.0228 and 981.0, respectively).