直观推导式演进特征投影法测定不同方法提取的国产血竭中龙血素B的含量

利用HPLC-DAD产生的二维数据和化学计量学方法-直观推导式演进特征投影法（HELP），解析了不同提取方法得到的国产血竭中的重叠色谱峰，并对其中的指标性成分-龙血素B进行了含量测定，结果满意。这表明这化学计量学方法与现代分析手段有机结合，将为中药等复杂体系的分析提供一条新途径。     

直观推导式演进特征投影法分辨枸杞类胡萝卜素的异构体

采用高效液相色谱-二极管阵列检测方法,初步分离了枸杞子中的类胡萝卜素。以乙腈-二氯甲烷(体积比为60∶40)为流动相,流速为1.0 mL/min,用C18柱从枸杞类胡萝卜素中分离出7个峰。但由于类胡萝卜素的结构多样性,尤其是顺反异构体的出现使得分离并不完全。利用所得三维数据提供的信息和化学计量学方法直观推导式演进特征投影法(HELP),对其中某些在二维色谱中被定性为单组分的峰进行解析,结果发现原来在二维色谱中被定性为单组分的峰大多是一些多组分峰。以其中第4个峰为例对其进行解析,得到了该类胡萝卜素的同分异构体色谱流出曲线及紫外光谱信息。该方法表明,化学计量学方法与现代分析手段有机结合,大大降低了此类复杂体系对色谱分离的要求,对同分异构体的分析具有一定的借鉴和指导意义。     

直观推导式演进特征投影法及其在复杂体系分析中的应用

对直观推导式演进特征投影法(HELP)的原理及主要步骤作了简要介绍。综述了HELP的研究情况及其在中草药分析、环境样品分析等领域中的应用，并对该法的优势和发展趋势作出了讨论。     

直观推导式演进特征投影法解析多环芳烃的重叠色谱峰

用高效液相色谱法(HPLC)测定多环芳烃时,因芴、苊和菲,茚(1,2,3-cd)芘和苯并(g,h,i)苝的色谱峰严重重叠而影响测定结果。本研究用高效液相色谱-二极管阵列检测器(DAD)和荧光检测器(FLD)测定多环芳烃,在激发波长λex=230nm,发射波长λem=300～500nm范围内采集重叠峰的HPLC-FLD二维色谱数据,再用直观推导式演进特征投影法(HELP)解析它们的重叠色谱峰,分辨结果令人满意。该方法对重叠组分的分辨下限为0.02mg/L。结果表明,用二维色谱荧光数据解析色谱重叠峰,灵敏度更高,可用于环境样品中多环芳烃的测定。     

直观推导式演进特征投影法在拖尾重叠色谱峰解析中的应用

直观推导式演进特征投影法(HELP)已成功应用于复杂体系的重叠色谱峰解析.当色谱峰拖尾时,演进特征投影图(ELPG)显示的直线段对应的区域中可能含有前面拖尾组分的信息,据此进行HELP解析可能得不到满意结果.选择ELPG上直线段的一部分,即拖尾组分末端,前面组分的信息已基本消失的区域作为选择性区域进行HELP解析.同时,提出一种新的定量方法:用主成分分析法(PCA)分解待测组分标准样品的二维数据,将得到的“标准”色谱引入HELP的定量过程,在色谱峰拖尾或解得谱峰不平滑时,得到更准确的结果.用HELP方法解析了依诺沙星、诺氟沙星和环丙沙星三组分实验体系,结果表明,加入上述措施的HELP可有效改善拖尾重叠色谱峰的解析结果.     

直观推导式演进特征投影法对酶催化反应的过程分析

以丁香酸(syringic acid)为模型化合物, 研究了漆酶(laccase)催化降解木质素(lignin)的复杂生化反应过程, 设计了一种反应过程动态量测系统, 该系统可以在5 s的时间间隔测定反应体系在190～800 nm波长范围内的实时光谱信息. 利用固定窗口因子分析-直观推导式演进特征投影法(FSMWEFA-HELP), 解析反应过程中测得的实时动力学光谱数据矩阵, 得到反应物和中间体的数目及其浓度的变化和纯物质的光谱曲线, 并推导出合理的反应机理. 将所得结果与多元曲线分辨-交替最小二乘(MCR-ALS)方法进行了比较.     

直观推导式演进特征投影算法-气相色谱-质谱联用测定烟叶中挥发性组分

应用气相色谱-质谱法及直观推导式演进特征投影(HELP)算法测定了烟叶中的挥发性组分.取经干燥及粉碎的烟叶样品用加速溶剂萃取法在160℃用乙醇提取15 min,所得提取液经吹氮蒸缩至1.5 mL,取1μL进样分析,采用DB-5MS毛细管柱进行分离.质谱分析采用电子轰击离子源,在质荷比(m/z)30～500范围内进行扫描...     

高效液相色谱法结合化学计量学测定千里光中四种活性成分的含量

建立了测定千里光不同部位中绿原酸,芦丁,金丝桃苷和槲皮素含量的高效液相色谱-二极管阵列检测(HPLC-DAD)方法。采用Phenomenex C18色谱柱(250×4.6mm,5μm),以乙腈-水(含0.3%的甲酸)为流动相,流速1.0mL/min,梯度洗脱,检测波长350nm,柱温35℃,运用直观推导式演进特征投影法(HELP)对重叠峰进行分辨。实验结果表明:四组分分别在各自相应浓度范围内线性关系良好,线性相关系数均大于0.998,平均加样回收率在82.64%~94.82%之间,相对标准偏差为2.94%~9.36%。该方法简单、快速、准确、可靠,适用于千里光中四种成分的同时测定。     

反相高效液相色谱检测丹参药材中4种丹参酮的含量

建立了测定丹参药材中4种丹参酮含量的反相高效液相色谱法，色谱条件：流动相为水(含0．5％三乙胺)-甲醇-四氢呋喃(45／55／5，V／V／V)，流速为1mL/min；PDA检测波长254m；4种成分丹参酮Ⅰ、丹参酮ⅡA、隐丹参酮和二氢丹参酮的加样回收率在95．1％-101．2％之间，线性范围为0．08-2μg。该方法准确，稳定，重现性好。根据该色谱条件，测定了不同产地的丹参药材，结果表明：该色谱方法准确检测了生药中4种丹参酮的含量，适合于丹参药材的质量控制。     

丹参中3种丹参酮的超临界二氧化碳萃取及液相分析

 用超临界CO2 流体及共溶剂乙醇萃取丹参中的 3种丹参酮 ,分别采用正交设计法和系统法考察了萃取中的主要影响因素 ;采用高效液相法 (HPLC) ,在甲醇 水 (体积比为 80∶2 0 )溶液为流动相和检测波长为 2 80nm的条件下 ,以外标法检测了萃取产物中 3种丹参酮的含量。实验得到的最佳条件为 :萃取压力 2 0MPa ;萃取温度 4 5℃ ;分离温度 35℃ ;共溶剂 95 % (体积分数 )乙醇 ;流量 1 0mL/min。建立的HPLC测定方法简便快捷 ,准确度高 ,重现性良好 ,相关系数r为 0 9994～ 0 9998,相对标准偏差RSD为 2 37%～ 3 4 7%。     

微柱高效液相色谱法测定丹参中的几种有效成分

研究了用微柱高效液相色谱法测定丹参中的4种有效成分(丹参素,原儿茶酸,原儿茶醛,丹酚酸B)的方法。丹参样品中的几种有效成分用体积分数40%的甲醇超声振荡提取,然后以WatersXterraTMRP18(1.0×50mm,2.5μm)微柱为固定相,甲醇和体积分数1%的HAc溶液梯度洗脱为流动相分离,在该色谱条件下,丹参中的4种有效成分在4.0min内可达到基线分离;用紫外二极管矩阵检测器检测。方法标准回收率为97%~102%,相对标准偏差为1.6%~2.3%。用此方法可测定几种丹参样品中的有效成分。     

丹参药材水溶性成分的高效液相色谱指纹图谱研究

采用高效液相色谱法(HPLC)对贵州铜仁丹参基地的丹参药材进行了指纹图谱研究。实验采用Zorbax SB-C18色谱柱 (5 μm, 4.6 mm i.d.×250 mm),以乙腈-0.4%(体积分数)冰醋酸水溶液为流动相,乙腈的体积分数在70 min内由0线性 增加到40%;流速1.0 mL/min;柱温25 ℃;检测波长254 nm。以19个主要共有峰为评价指标,采用国家药品监督管理局推荐 的“计算机辅助中药指纹图谱相似度计算软件”计算处理,建立了铜仁地区丹参药材的HPLC共有指纹图谱。该法操作简单 ,精密度、稳定性和重现性良好,有助于加强丹参药材的质量控制。     

微波辅助萃取与超声波萃取丹参中丹酚酸B的比较研究

本文对微波辅助萃取和超声波萃取丹参中丹酚酸B进行了比较研究,并用高效液相色谱法(HPLC)测定了丹参中丹酚酸B.考察了微波辅助萃取和超声波萃取参数的影响,在各自最佳萃取条件下进行了丹参中的丹酚酸B提取率的比对,结果表明:微波辅助萃取6 min的提取率高于超声波萃取30 min的提取率.微波辅助萃取法与超声波萃取法相比具有省时、高效和溶剂用量少的特点.利用指纹图谱比较了两种萃取方式提取的化学成分的差异,结果显示两种萃取方法提取的主要成分组成基本相同,其共有成分比例相近.     

Analysis of PAHs in air-borne particulates in Hong Kong City by heuristic evolving latent projections

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直观推导式演进特征投影法对环境样本中多环芳烃的定性定量分析

基于新近发展的直观推导式演进特征投影法(HELP), 本文提出了一个对二维数据进行同时定性定量的分析方法, 并将其成功地用于环境样本中多环芳烃化合物定量解析。对于一维色谱难以定量的重叠峰, HELP方法充分利用色谱、光谱两方面的选择性信息, 得到了具有真实物理意义的唯一解。在定性分辨结果的基础上, 本文还提出了三种可能的定量方法。这种二维数据的解析新方法, 能大幅度地降低对色谱分离条件的要求, 可直接用于复杂实际样本的定性定量分析。     

丹参木质素及其单体含量的测定

本文建立了一种准确、快速的检测丹参中木质素及其单体含量的方法.采用Klason法和紫外分光光度法分别对丹参根和茎中酸不溶性木质素(Klason木质素)和酸溶性木质素含量进行了测定;运用硫代酸解法并结合气相色谱-质谱法(GC-MS)分别对丹参根和茎中各木质素单体组成进行了分析.结果显示,总木质素在丹参根和茎中的含量分别为...     

Quality evaluation of Salvia miltiorrhiza Bge. by ultra high performance liquid chromatography with photodiode array detection and chemical fingerprinting coupled with chemometric analysis

An ultra high performance liquid chromatography with photodiode array detection method is developed for the simultaneous quantitative determination of five water‐soluble compounds including danshensu, protocatechualdehyde, rosmarinic acid, salvianolic acid B, and salvianolic acid A in Salvia miltiorrhiza Bge. samples. Through method optimization, the five compounds all expressed good linearity (R² > 0.9990) in a wide concentration range together with satisfactory accuracy, precision, and stability. Moreover, through qualitative analysis of the chemical fingerprint combined with similarity analysis, hierarchical cluster analysis, principle component analysis, and partial least‐squares discriminate analysis, we determined that the 13 batches of Salvia miltiorrhiza Bge. were similar in internal quality and the differences resulted from various cultivation environments, recovery elements, and others. Seen from the results of hierarchical cluster analysis and principle component analysis, the classification of 13 batches was in accordance, and partial least‐squares discriminate analysis technique was more suitable than the principle component analysis model to provide a distinct classification of test samples on the basis of their different components. Moreover, a permutation test verified the rationality of partial least‐squares discriminate analysis and variable importance plot showed that peaks 37 and 38 were the most significant variables in distinguishing the Salvia miltiorrhiza Bge. samples. The idea of the quantitative and qualitative analysis of Salvia miltiorrhiza Bge. was convenient, sensitive, and comprehensive, which could be applied to evaluate the quality of more traditional Chinese medicines.     

Determination of Pharmacokinetics of Tanshinone II A in Mouse Plasma and Brain by High Performance Liquid Chromatography

High performance liquid chromatography (HPLC) method was developed to measure the concentration of tanshinone IIA (Ts IIA) in mouse plasma and brain. The method was applied to preliminary study on pharmacokinetics of Ts IIA in mouse plasma and brain. After an administration of 8.0 mg kg⁻¹ of Ts IIA by an intravenous injection, plasma and brain samples were collected and extracted by liquid-liquid extraction with ethyl acetate and determined by HPLC. This method has a linear range from 0.05 to 7.12 mg l⁻¹ with correlation coefficients of 0.9984 in plasma and a linear range from 0.022 to 2.37 mg l⁻¹ with correlation coefficients of 0.9988 in brain. The limits of quantitation in plasma and brain were 0.050 and 0.022 mg l⁻¹, respectively, and the limits of detection were 0.026 and 0.017 mg l⁻¹, respectively. The intra-day and inter-day precisions were less than 10.3%. The developed method was selective, accurate, and sensitive and can be applied to determine the concentration of Ts IIA in mouse plasma and brain quantitatively after intravenous administration of Ts IIA. It was suitable for the pharmacokinetic study of Ts IIA. The plasma concentration-time curve was fitted as three-compartment model. The peak concentration of Ts IIA in mouse plasma was 1.58 mg l⁻¹, and the value of the areas under the plasma concentration-time curve (AUC 0-t) was 68.18 mg l⁻¹ min⁻¹. The concentration of Ts IIA in mouse brain achieved the peak value of 0.17 mg l⁻¹ 5 min after mainlined, and Ts IIA could be still detected in brain 480 min after mainlined. The results indicated that Ts IIA readily penetrated the blood-brain barrier and could stay in the brain for a long time.     

Discrimination of Acori Tatarinowii Rhizoma and Acori Calami Rhizoma based on quantitative gas chromatographic fingerprints and chemometric methods

This study was conducted to investigate the chemical differences between Acori Tatarinowii Rhizoma and Acori Calami Rhizoma using gas chromatography with mass spectrometry and chemometric methods. Quantitative fingerprints were established. A total of 90 volatile compounds were identified and quantified using heuristic evolving latent projection and retention index. An efficient model based on partial least squares‐discriminant analysis coupled with variable iterative space shrinkage approach was developed to distinguish Acori Tatarinowii Rhizoma from Acori Calami Rhizoma. The correct rate was 95.83%, and the area under the receiver operating characteristic curve was 100%. Finally, three volatiles, namely, camphor, longicyclene, and δ‐cadinene, were selected as key discrimination factors between Acori Tatarinowii Rhizoma and Acori Calami Rhizoma. The proposed protocol can serve as a valid strategy for quality control and screening of potential bioactive components of herbal medicines.