高效液相色谱法测定超滤后血清中的假尿苷

用高效液相色谱法（ＨＰＬＣ）直接测定了超滤后血清中的假尿苷（ＰＳＥ）,平均回收率为９７．７８％,在０．０９３～６μｍｏｌ范围内呈线性关系（γ＝０．９９５６）,急性白血病患者血中ＰＳＥ水平显著高于正常对照组（Ｐ＜０．０１）。该方法简单、方便、迅速,可用于恶性病的病情及疗效监测。     

X—射线荧光光谱测定甜瓜中矿质元素

报道了日本理学３０８０Ｅ３型Ｘ－射线荧光光谱仪在测定甜瓜样品旧和微量矿质元素中的的应用。以国家植物标准参考物质（ＧＢＷ）为校准标样，采用真空加热干燥法制备甜瓜样品，所得分析结果与ＩＣＰ－ＡＥＳ对照相吻合。     

扫描定点法在Si/Mo多层膜材料深度剖面分析中的应用

用对比方式对分割成二等分的同一Ｓｉ／Ｍｏ多层非晶薄膜样品分别作了ＲＡＳ－ＰＯＩＮＴ ＭＯＤＥ和ＰＯＩＮＴ ＭＯＤＥ的二次离子质谱深度剖面分析,前者是把ＲＡＳ ＭＯＤＥ（扫描法）与ＰＯＩＮＴ ＭＯＤＥ（定点法）有效结合起来的一种方法,即所谓扫描一定点法。实验证明,扫描一定点法有效地克服了弹坑效应（Ｃｒａｔｅｒ ｅｆｆｓｃｔｓ）。     

聚醚砜流变性能的研究

用锥板流变仪测试了分子量不同的国产聚醚砜（ＰＥＳ）样品的流变性能。结果表明ＰＥＳ具有剪切变稀的特性，所得的粘流活化能与文献报道的ＩＣＩ产品值相近。根据求得的零剪切粘度（ηｏ）与分子量的关系推断样品的分子量已经接按临界分子量（Ｍｃ），并利用转换因子αＩ＝ηｏＴ／ηｏ（ＴＲ）绘制了样品的叠合曲线，得到较好的叠加效果，同时还求得了ＷＬＦ方程的两个经验常数Ｃ１和Ｃ２的数值。     

嵌段—接枝共聚物SPEG与PS（OH）之间的氢键络合导致胶束化的研究

利用原子转移自由基聚合反应合成了以聚苯乙烯－ｂ－聚（乙烯－ｃｏ－丙烯）（ＳＥＰ）为主链、无规分布且数目可控的聚甲基丙烯酸乙酯（ＰＥＭＡ）为支链的嵌段接枝共聚物ＳＰＥＧ,发现在甲苯中因支链ＰＥＭＡ与聚（苯乙烯－ｃｏ－对六氟丙基－α－甲基苯乙烯）「简称ＰＳ（ＯＨ）」的氢键络合作用和ＥＰ嵌段的溶解作用导致了聚集体的胶束化,研究了胶束的尺寸及其分布对ＰＳ（ＯＨ）中羟基含量和共混物组成的依赖性。     

聚醚砜流变性能的研究

用锥板流变仪测试了分子量不同的国产聚醚砜（ＰＥＳ）样品的流变性能．结果表明ＰＥＳ具有剪切变稀的特性，所得的粘流活化能与文献报道的ＩＣＩ产品值相近．根据求得的零剪切粘度（η０）与分子量的关系推断样品的分子量已经接近临界分子量（ＭＣ），并利用转换因子αＩ＝η０Ｔ／η０（ＴＲ）绘制了样品的叠合曲线，得到较好的叠加效果，同时还求得了ＷＬＦ方程的两个经验常数Ｃ１和Ｃ２的数值．     

聚醚醚酮酮（PEEKK）和含联苯结构聚醚醚酮酮（PEBEKK）共聚物的SAXS研究

应用一维电子密度相关函数方法，对含不同联苯结构的ＰＥＥＫＫ－ＰＥＢＥＫＫ共聚物样品小角Ｘ射线散射（ＳＡＸＳ）去模糊强度分析计算表明：ＰＥＥＫＫ－ＰＥＢＥＫＫ共聚物的聚集态结构明显地依赖于共聚物中联苯含量。当联苯含量ｎｂ＝０．３５时，积分不变量Ｑ，长周期Ｌ，平均结晶片层厚ｄ，电子密度差η_ｃ－η_ａ和结晶度Ｗ_（ｃ，ｘ）值为最小，比表面积Ｏ_ｓ为最大。     

分子链大尺度取向对非晶态聚对苯二甲酸乙二酯结晶行为的影响

用ＤＳＣ和溶剂诱导结晶（ＳＩＮＣ）的方法对比研究了（ＧＯＬＲ）态和未取向聚对苯二甲酸乙二酯（ＰＥＴ）纤维样品的结晶行为．实验结果表明，样品的大尺度取向可有效地降低样品的冷结晶温度（Ｔｃｃ），证明大尺度取向对样品的结晶行为可起到促进作用．     

刚性链嵌段共聚物的研究（Ⅳ）──聚醚醚酮／苯酞圈型聚芳醚砜有规嵌段共聚物的合成与部分性能

以聚醚醚酮（ＰＥＥＫ）和苯酞圈型聚芳醚砜（ＰＤＣ）齐聚物为原料，通过溶液缩聚法制备了ＰＥＥＫ／ＰＤＣ有规嵌段共聚物系列样品。经ＤＳＣ、ＷＡＸＤ、ＴＧＡ、ＤＭＡ等方法研究表明：共聚物没有微相分离现象；其结晶属于简单正交晶系，ＰＤＣ含量对共聚物结晶行为产生很大影响；热稳定性随ＰＤＣ含量增加而明显降低；共聚物具有优异的力学性能，拉伸强度和储能模量高于ＰＥＥＫ。     

RPS／CPE的反应性共混及其对PS／PE的增容作用

用ＦＴＩＲ、ＤＳＣ等方法研究了含恶唑啉官能力的聚苯乙烯（ＲＰＳ）与氯化聚乙烯（ＣＰＥ）之间的反应。ＲＰＳ、ＣＰＥ、ＰＳ、ＰＥ在不同温度下用反应式挤出要熔融共辊，结果表明，ＲＰＳ／ＣＰＥ对ＰＳ／ＰＥ共混物具有增容作用，提高了共混物的力学性能。此反应性共混适宜在较低温度下进行，对ＲＰＳＣＰＥ共混物还进行了动态力学表征，并与ＲＰＳ进行比较以进一步了解共混物的特征。     

Analysis of Organic Pollutants in Surface Water by Solid-Phase Extraction and Gas Chromatograph-Mass Spectrometry

Solid-phase extraction (SPE) is an emerging chromatographic sample preparation technique. The novel extraction technique can reduce the time and volume of organic solvents required, and alleviate problems associated with the formation of emulsions as compared to conventional liquid-liquid extractions. This study was designed to apply SPE vacuum manifold to determine organic pollutants in surface water of Huan River binding with GC-MSD system.     

Electric Field-Assisted Solid Phase Extraction: Devices, Development and Application with a Cationic Model Compound

This work describes novel devices for electric field-assisted solid phase extraction (E-SPE) and an application was carried out on the antimicrobial marbofloxacin (MAR). Conventional syringe-type SPE cartridges were easily adapted to receive two electrodes that were inserted and positioned below and above the sorbent. The adapted cartridges were coupled to a flow extraction system, which consisted of an electrophoresis power supply, a peristaltic pump and a homemade SPE manifold. These devices were used to apply electric fields during the extraction of MAR from fortified buffer and milk samples. The recovery of MAR was improved (2.3 times) or reduced (4.2 times) in comparison to conventional SPE when the top electrode was used as cathode (E-SPE_(?/+)) or anode (E-SPE_(+/?)), respectively. The results demonstrated that usual SPE cartridges can be easily and inexpensively adapted for applying an electric field in SPE. It was also concluded that the electric field applied in a usual SPE cartridge can be employed as a new suitable approach to enhance the extraction efficiency of ionic compounds in a complex sample matrix.     

Miniaturisation of solid phase extraction method for determination of retinol,alpha- and gamma-tocopherol in human serum using new technologies

The aim of this study was to develop rapid and simple solid phase extraction (SPE) and HPLC methods for simultaneous determination of retinol, gamma- and alpha-tocopherol in human serum using a special auto sampler with micro titration plates.

Separation of vitamins was performed at ambient temperature using monolithic column on a HPLC containing rack changer for micro titration plates. As the mobile phase methanol with flow rate 2.5 mL min^?1 was used. The injection volume was 20 µL. Retinol was detected at 325 nm, gamma- and alpha-tocopherol were carried out at 295 nm, respectively. The total time of analysis was 1.8 minutes. Extraction method was developed using Spe-ed 96 C18, 100 mg/2 mL micro titration plates and SPE vacuum manifold. The consumption of the sample was 50 µL. Time of the analysis for 96 samples on one micro titration plate was 1.5 hour. In order to validate the developed method, precision, accuracy, linearity, detection and quantitation limits were evaluated. This method is suitable for rapid automated large-batch analysis of retinol, alpha- and gamma-tocopherol in small sample volumes of human serum.     

Solid-Phase Extraction and LC with Fluorescence Detection for Analysis of PAHs in Rainwater

The efficiency of extraction of polycyclic aromatic hydrocarbons (PAHs) from rainwater by solid-phase extraction (SPE) with three different types of cartridge, and analysis by high-performance liquid chromatography with fluorescence detection, are discussed in this paper. Three cartridges were investigated but only one was suitable. After equilibration in a desiccator for 65–80 h or in ambient air for 90–100 h the SPE cartridges were activated with 5 mL dichloromethane then 5 mL 2-propanol. The volume of sample passed through the cartridges was 50 mL; after loading of the sample the cartridges were dried under vacuum for approximately 20 min by application of a pressure of 15 mbar to the SPE manifold. The PAHs were eluted with 5 mL dichloromethane–hexane, 50:50 (v/v). The flow rate used for conditioning, sample loading, and elution was 2.5 mL min⁻¹, achieved by application of a pressure of 6 mbar. For analysis of PAHs in rainwater, recovery was between 67 and 99%, the relative standard deviation varied between 2 and 5%, and the detection limits of the method were less than 16.9 ng L⁻¹ for several PAHs. These optimum conditions were used for analysis of rainwater collected between June 2002 and May 2003 at two sites in Alsace (eastern France) and 17 PAHs were quantitatively determined. Concentrations varied between 1.6 and 968.1 ng L⁻¹.     

固相萃取技术在磺胺类药物残留分析中的研究进展

磺胺类药物(Sulfonamides,SAs)残留与食品安全水平息息相关。存在SAs残留的基质复杂多样,开发快速、高效、高选择性的前处理方法是检测的关键。固相萃取(SPE)具有较少的溶剂使用量、绿色环保、高选择性、高灵敏度、节省时间、成本低、能与不同检测手段兼容等特点,已被广泛应用于SAs残留的前处理过程。该文简要介绍了移液枪头式SPE、磁性SPE、分子印迹SPE、管内SPE和其他SPE模式,并总结了它们在SAs残留检测分析中的研究进展。     

Solid-phase extraction for multiresidue analysis of organic contaminants in water

To overcome the limitations of the detection systems associated with gas or liquid chromatography, a sample pretreatment is required with the objective to provide a sample fraction enriched with all the target analytes and as free as possible from other matrix components. There is now no doubt that solid-phase extraction (SPE) has now become the method of choice for carrying out simultaneously the extraction and concentration of many compounds in aqueous samples. Many recent applications of SPE to multiresidue analysis are reviewed with an emphasis on the importance of the choice of the sorbent and of the sample volume. SPE is particularly well adapted to multiresidue analysis including compounds from a wide range of polarity or characterized by various physico-chemical properties. However, SPE is not completely free from practical problems inherent to the nature of the compounds or to the coupling to the chromatographic systems. Many examples are reported to illustrate these problems which can in most cases be circumvented. New developments in SPE are also reviewed.     

Determination of polynuclear aromatic hydrocarbons in aerosol by solid-phase extraction and gas chromatography-mass spectrum

The optimum procedures for clean up aerosols in silica solid-phase extraction (SPE) cartridge prior to the analysis of polynuclear aromatic hydrocarbons (PAHs) by gas chromatography–mass spectrum (GC–MS) in selected ion monitoring detection mode have been investigated. The silica SPE cartridge is activated by dichloromethane and hexane, and then dried up by vacuum in SPE instrument for about 5 min. The sample volume loaded on the cartridge is 3 ml and after loading the sample the cartridge was dried in vacuum for 5 min. The PAHs were eluted from the cartridge by 3 ml 20% dichloromethane in hexane. The flow-rate of sample loading and eluting was controlled in about 1 ml min⁻¹. The aerosols collected on the campus of Beijing Normal University from August 2001 to July 2002 have been processed with these optimum procedures and 16 EPA priority pollution PAHs in the aerosols have been quantitatively determined.     

Determination of niacin in infant formula and wheat flour by anion-exchange liquid chromatography with solid-phase extraction cleanup

Niacin content must be included on food labels of infant formula products and bakery products containing enriched flour. Liquid chromatographic (LC) determination of niacin in complex food matrixes is complicated by the presence of endogenous compounds that absorb at the commonly used wave-length of 260 nm. Also, the presence of particulate matter in the standard sulfuric acid extraction procedure results in reduced life of LC columns and precolumns. A simple, rapid, solid-phase extraction (SPE) procedure for separation and cleanup of niacin from a complex food matrix digest has been developed. By using a vacuum manifold with the SPE column system, multiple samples can be processed quickly and efficiently for LC analysis, compared with gravimetric column cleanup. Sulfuric acid sample digest is passed over an aromatic sulfonic acid cation-exchange (ArSCX-SPE) or a sulfonated Florisil SPE column. Niacin is eluted with 0.25M sodium acetate-acetic acid, pH 5.6 buffer in vacuo. LC chromatograms of the resulting eluate are free of interference from other components absorbing at 260 nm at the retention time of niacin. Validation of the method was obtained from agreement of analytical results on available reference materials. For both SPE methods, values for niacin in SRM 1846 Infant Formula (milk-based powder) were within uncertainty ranges of the certified value. Use of several calibration procedures (the LC computer program, a peak area response graphic standard curve, or the method of standard additions) with both SPE procedures resulted in niacin values for 3 RM-Wheat Flours (not certified for niacin) in agreement (90-105%) with their respective values reported in the literature. Several commercial wheat flours showed a broad 260 nm interference, resulting in high niacin values. Niacin recoveries from spiked soy-based liquid infant formulas ranged from 95-107% with the ArSCX-SPE column. Calibration curves of niacin were linear up to 400 micrograms/mL, with a detection limit of 0.2 microgram/mL.     

Fluorimetric determination of fluoride in a flow assembly integrated on-line to an open/closed FIA system to remove interference by solid phase extraction

A simple flow injection fluorimetric method for fluoride determination is proposed. The method is based on the enhanced fluorescence of quercitin-Zr(IV) complex when fluoride ion is present in the sample. An open/closed FIA manifold with a mini-column of Dowex 50W X8 resin was used to remove the most important interference (aluminum). The two FIA assemblies were integrated on-line to automate the pretreatment of the water sample and fluoride determination. The calibration graph was linear over the range 0.1-3.0 mug ml(-1) of fluoride with a correlation coefficient of 0.999 and LOD 0.06 mug ml(-1). The relative standard deviation was 2.5% and the sample throughput was 52 h(-1) without pretreatment and 10 h(-1) with pretreatment of the sample. The method was applied to the determination of fluoride in water samples.     

固相萃取吸附材料在植物激素样品前处理中的应用新进展

植物激素在植物生长过程中具有重要作用,调节植物生长、发育及抗逆的各个过程。植物激素超微精准定量分析一直是植物生理学研究的瓶颈问题。植物激素的准确、高效检测目前大多是基于液相色谱-串联质谱联用技术。样品前处理是植物激素色谱-质谱分析中必不可少的一个步骤,直接影响后续检测方法的灵敏度和准确性。在植物激素各种前处理方法中,固相萃取(SPE)技术应用非常广泛。在萃取小柱基础上发展了多种新形式(分散固相萃取、磁性固相萃取、固相微萃取等,称之为SPE相关方法)。在上述SPE相关方法中,吸附材料的选择均是关键因素,决定了样品前处理过程的目标物提取、净化和富集效果。碳基材料(包括碳纳米管、石墨烯、碳氮化合物等)和有机骨架材料(包括金属有机骨架、共价有机材料)拥有结构可设计、比表面积大、稳定性良好等特性,非常适合作为吸附材料。分子印迹聚合物和超分子化合物依靠主-客体特异性分子识别作用,能显著提高样品前处理方法的选择性。本文重点针对植物激素样品前处理中的SPE技术,综述了近5年来上述几类功能化吸附材料的最新应用进展,并对其发展趋势进行展望。