化妆品中碘丙炔醇丁基氨甲酸酯的高效液相色谱检测及质谱确证

建立了高效液相色谱(HPLC)-二极管阵列检测器(DAD)测定化妆品中碘丙炔醇丁基氨甲酸酯的方法.化妆品样品经超声提取后,高效液相色谱-二极管阵列扫描检测,并在235 nm波长进行分析.用保留时间结合紫外光谱定性,外标法定量,并采用液相色谱-质谱法确证.碘丙炔醇丁基氨甲酸酯的回收率为92.7%～99.8%,相对标准偏差在0.8%～2.1%之间,定量限为20 mg/kg.     

由液相色谱保留值变化规律式推荐液相色谱分离模式的研究

 提出了液相色谱柱系统选择的二个基本条件，在此基础上应用统计热力学导出保留值当变化规律式，建立了符合色谱柱系统选择条件的液相色谱分离模式的推荐规则，并利用色谱专家系统中液相色谱谱图库的110张谱图，对该分离模式的推荐规则进行了初步验证，结果表明二者能较好地相符。     

当归特征组分的识别与定量对比

 将高效液相色谱模式 /二极管阵列检测与自编紫外光谱库管理软件结合 ,用液相色谱 /紫外光谱以及特征参数研究同种当归多个特征组分的识别及快速定量对比。色谱 /光谱及其特征参数共同表达同种当归 2 3个特征组分 ;探讨定量对比的关键技术 ;定量比较两个同种当归相同组分的浓度差异。多指标表达当归特征组分 ,可用于它们的识别 ;定量手段的建立 ,可对比当归特征组分定量结果的差异性。不用化学对照品 ,便能识别和定量比较当归样品中的多组分。方法简便易行、快速 ,结果的代表性强、重现性良好。     

新型标准品4氯-2-甲基苯胺的制备与表征

制备和纯化了4-氯-2-甲基苯胺标准品。通过高效液相色谱、红外光谱、紫外光谱、质谱、核磁共振谱图的测定，确认了其化学结构。使用质量平衡法和定量核磁共振方法联合定值，并进行了均匀性、短期和长期稳定性的评估和特征值的表征。定值结果为99.8%±0.09%(k=2, P=0.95)。该标准品量值具有溯源性和准确性，可以为监测杀虫脒提供可靠的标样支撑。     

智能色谱法的发展（上）

本文综述了我们在智能色谱方面的发展,包括硬件和软件两个主要部分.第一部分评述了细管径高效液相色谱柱,不可抽提的气相色谱毛细管柱,无阀切换技术,四合一组合检测器和快速扫描紫外光谱检测器;第二部分包括三个应用软件:保留值预测.最佳操作条件预测和全谱图拟含软件,并用大量实验证明了保留值方程的正确性。这些方程用于定性分析及最佳条件选择,文中举出了有关的例子,讨论了细管径高效液相色谱,不可抽提的气相毛细管柱、柱切换系统、组合检测器、快速扫描紫外检测器、曲线拟合方法在智能色谱中的应用。     

由液相色谱保留值变化规律式推荐液相色谱分离模式的研究

提出了液相色谱柱系统选择的二个基本条件,在此基础上应用统计热力学导出保留值变化规律式,建立了符合色谱柱系统选择条件的液相色谱分离模式的推荐规则,并利用色谱专家系统中液相色谱谱图库的110张谱图,对该分离模式的推荐规则进行了初步验证,结果表明二者能较好地相符。     

全二维气相色谱/飞行时间质谱法快速定性分析飞灰样品中的二噁英

建立了全二维气相色谱/飞行时间质谱法 (GC×GC-TOFMS) 快速定性分析飞灰样品中17种二(噁)英的方法.实验证明,采用GC×GC二维特征谱图、TOFMS谱图库检索(自建谱库和NIST库)以及丰度比的定性手段,能在42.5 min内快速分离和定性17种二(噁)英的同分异构体.本方法对大于 0.5 pg/μL (TCDD) 的样品有较好的灵敏度.因此,在二(噁)英分析领域,GC×GC/TOFMS技术可以作为高分辨气相色谱/质谱(HRGC/HRMS)技术的补充和替代.     

高效除草剂快杀捭标准物质的制备及表征

从快杀捭工业品出发，经活性炭纯化、硅胶柱层分离制得快杀稗标准物质，并进行熔点、高效液相色谱、紫外光谱、元素分析、红外光谱、质谱、核磁共振等方法的表征，以高效液相色谱法测得该标准品的纯度在99%以上。     

倍硫磷的气相色谱/红外光谱检测

倍硫磷是我国常用农药品种，也是是 口大米的必检项目之一。本文应用气相色谱／红外光谱联用方法，探索了倍硫磷的最佳色谱条件，获得其气以谱／红外光谱图，并依靠已有的气相红外谱库进行了检索，拟建立倍硫磷的气相色谱／红外谱库，以用于农产品中该农药的GC／FTIR监控。     

水溶性维生素高效液相色谱分析方法的自动设计

应用计算机技术在人类专家水平上进行实际样品的高效液相色谱分析方法的设计一直是人们追求的目标。我们在研制色谱专家系统的过程中,注意到正在发展的一些色谱专家系统中的问题,首次把人工智能的研究方法和某些数学算法相结合,同时建立了为检验推理正确与否的谱图库。为了在人类专家水平上自动地进行高效液相色谱分析方法的设计,我们在IBM PC/XT微机上发展了带有快速扫描光二极管列阵检测器的全盘自动化高效液相色     

中药方剂化学成分液质联用分析中标准质谱库的建立和应用

利用电喷雾离子化四级杆飞行时间串联质谱(ESI-Q-TOF)技术,以四物汤类方为例,建立了类方成分的液质联用分析质谱库。利用Masslynx工作站的Chromalynx模块的检索和与质谱库比较的功能,可以快速鉴定色谱图中各个色谱峰。此方法可应用于液质联用检测系统的谱库检测,提高了对类方成分鉴定的效率和可靠性。本质谱库共收录了液质联用条件下57个四物汤类方标准品的质谱信息,包括正负离子模式下各成分的保留时间、准分子离子峰及其碎片离子的精确质量数。该质谱库支持标准NIST谱图检索及比对方法,可自动完成总离子流色谱图中各色谱峰的识别、质谱图提取及鉴定。     

Tandem mass spectral library of microcystins and related compounds

The initial version of the new tandem mass spectral library of microcystins, toxic metabolites of cyanobacteria, and related compounds, is considered. There are 75 spectra of 28 compounds entered in the library. The library was tested by corresponding library searches which led to the true positive rate of ≥73%. A library search performance and enlargement of the library are discussed.     

Multiple on‐line HPLC coupled with biochemical detection methods to evaluate bioactive compounds in Danshen injection

On‐line high performance liquid chromatography (HPLC) coupled with three biochemical detection (BCD) methods was applied to evaluate bioactive components in Danshen injection. On‐line HPLC‐photo‐diode array–fluorescence detection based on the fluorogenic substrate 7‐acetoxy‐1‐methyl quinolinium iodide, was built to search acetylcholinesterase (AChE) inhibitors in Danshen injection. On‐line HPLC coupled with the scavenging assay of 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) and 2,2′‐azinobis (3‐ethylbenzothiazoline‐6‐sulfonic acid) (ABTS) free radicals was developed to screen antioxidants. The three active profiles were obviously different. Radical scavenging profiles revealed seven strong peaks in the chromatographic fingerprint possessing obvious free radical inhibition effects, while some minor peaks exhibited stronger AChE inhibition activities. The main radical scavengers and AChE inhibitors were identified by HPLC‐MS. Several unknown ingredients showing strong AChE inhibition activities needed further identification except protocatechuic aldehydrate, salvianolic acid H or I and lithospermic acid. The on‐line multiple on‐line HPLC‐BCD methods will provide powerful tools in the field of pharmacognosy for fast‐track identification of interesting and/or novel bioactive compounds.     

高效液相色谱-圆二色检测法分析甲霜灵的对映体纯度

以手性农药甲霜灵为研究对象,使用非手性高效液相色谱在不拆分对映体的条件下,利用圆二色检测器所测的各向异性系数(g)测定手性对映体纯度。实验结果表明,g与对映体过剩率(ee)具有良好的线性关系;通过比较g所测ee与手性色谱所测的ee,二者所测ee相对平均偏差小于3.0%,说明该方法具有较高的准确性,可应用于手性化合物对映体纯度的测定。     

Determination of Six Bioactive Compounds in Buyang Huanwu Decoction by High Performance Liquid Chromatography Coupled with Electrospray Mass Spectrometry

A high performance liquid chromatography (HPLC) coupled with an electrospray mass spectrometry (ESI-MS) method was developed for the determination of six bioactive compounds in a Buyang Huanwu decoction (BYHWD), which was composed of seven spices of Traditional Chinese Medicines (TCMs). The separations were performed on a Shim-pack (VP-ODS) C₁₈ analytical column (5 μm, 250 × 4.6 mm ID, Shimadzu, Kyoto, Japan) with the column temperature maintained at 30°C. A linear gradient elution of A (0.1% formic acid solution) and B (100% acetonitrile) was used at a flow rate of 0.8 mL/min. The six compounds in BYHWD were identified by an Agilent-1100 HPLC system with a photodiode array detector coupled with an LC/MSD Trap SL electrospray ion mass spectrometer, and the contents of these compounds were determined by a Shimadzu 20A HPLC system coupled with a LCMS-2010EV quadrupole mass spectrometer. The standard calibration curves were linear with regression coefficient r² > 0.99. The intra-day and inter-day precisions of this method were evaluated with the relative standard deviation values (less than 2.06% and 2.88%, respectively). The recoveries of the six investigated compounds exceeded 96%. This method was successfully used to determine the six target compounds in BYHWD.     

A quantitative measure of the reliability of searches of spectral libraries

A quantitative measure of library search reliability has been developed. Applications of the quantitative reliability metric (QRM) for evaluating the reliability of library searches for unknown target spectra and the use of this measure to detect the failure of a library search caused by noise, contaminant peaks and missing library spectra are discussed. The effects of noise and composite infrared spectra of mixtures on the QRM are examined for test sets of 561 infrared spectra. The QRM is also used to evaluate the performance of a search of an infrared library compressed by eigenvector projection.     

A combinatorial approach to recognition of chirality: preparation of highly enantioselective aryl-dihydropyrimidine selectors for chiral HPLC

A parallel library of 108 4-aryl-1,4-dihydropyrimidine (DHPM) enantiomers, which are potential selectors for chiral HPLC separations, was synthesized using the single-step Biginelli multicomponent condensation. The individual compounds were screened by observing the enantioselectivity for resolution on a "brush-type" L-(3,5-dinitrobenzoyl)leucine-based chiral stationary phase, and separation factors alpha up to 12 were achieved. The best candidates from the library contained an ortho-substituted aromatic group at C4 carbon atom of the pyrimidine ring and an alkyl substituent at N1 nitrogen atom. Resolution of the enantiomers of the lead compound, 4-(9-phenanthryl)-DHPM 8, using semipreparative chiral HPLC followed by attachment to monodisperse macroporous aminomethacrylate beads, provided the novel polymer based chiral stationary phase with good enantioselectivities in the resolution of several pi-acidic aryl-dihydropyrimidines and derivatized profens. In addition, 3,5-dinitrobenzamido derivatives of alpha-amino acids could be resolved under normal phase HPLC conditions with separation factors up to 8.     

2,6-Diketopiperazines from amino acids, from solution-phase to solid-phase organic synthesis

A method to prepare 1,3-disubstituted 2,6-diketopiperazines (2,6-DKP) as useful heterocyclic library scaffolds in the search of new leads for drug discovery is described. The method can be used in solution-phase and solid-phase conditions. In the key step of the synthesis, the imido portion of the new molecule is formed in solution through intramolecular cyclization, under basic conditions, of a secondary amide nitrogen on a benzyl ester. A Wang resin carboxylic ester is used as the acylating agent under solid-phase conditions, allowing the cyclization to take place with simultaneous cleavage of the product from the resin ("cyclocleavage"). The synthetic method worked well with several couples of amino acids, independently from their configuration, and was used for the parallel synthesis of a series of fully characterized compounds. The use of iterative conditions in the solid phase (repeated addition of fresh solvent and potassium carbonate to the resin after filtering out the product-containing solution) allowed us to keep diastereoisomer content below the detection limit by HPLC and (1)H NMR (200 MHz).     

Fast gradient elution reversed-phase liquid chromatography with diode-array detection as a high-throughput screening method for drugs of abuse. II. Data analysis

In Part I of this work, we developed a method for the detection of drugs of abuse in biological samples based on fast gradient elution liquid-chromatography coupled with diode array spectroscopic detection (LC-DAD). In this part of the work, we apply the chemometric method of target factor analysis (TFA) to the chromatograms. This algorithm identifies the target compounds present in chromatograms based on a spectral library, resolves nearly co-eluting components, and differentiates between drugs with similar spectra. The ability to resolve highly overlapped peaks using the spectral data afforded by the DAD is what distinguishes the present method from conventional library searching methods. Our library has a mean list length (MLL) of 1.255 and a discriminating power of 0.997 when both retention index and spectral factors are considered. The algorithm compares a library of 47 different compounds of toxicological relevance to unknown samples and identifies which compounds are present based on spectral and retention index matching. The application of a corrected retention index for identification rather than raw retention times compensates for long-term and column-to-column retention time shifts and allows for the use of a single library of spectral and retention data. Training data sets were used to establish the search and identification parameters of the method. A validation data set of 70 chromatograms was used to calculate the sensitivity (correct identification of positives) and specificity (correct identification of negatives) of the method, which were found to be 92% and 94%, respectively.