应用于全氟辛烷磺酸萃取富集的全氟癸基修饰毛细管硅胶整体柱的制备及应用

利用溶胶-凝胶法,经过烷氧基硅烷的水解、硅羟基的缩聚、凝胶化、陈化、中孔制备、干燥和表面修饰等步骤制备了全氟癸基修饰的毛细管硅胶整体柱。采用该整体柱对全氟辛烷磺酸(PFOS)进行萃取富集,考察其富集特性和效率,并与传统的C18毛细管硅胶整体柱进行对比。结果表明,全氟癸基修饰毛细管硅胶整体柱(15 cm×75 μm)对PFOS具有更高的吸附量和更好的富集选择性,其平均吸附量可以达到75 ng;样品中PFOS的质量浓度为0.25 mg/L时,富集倍数平均可以达到29倍。此全氟癸基修饰毛细管硅胶整体柱对PFOS具有良好的萃取富集性能,可用于水质中痕量PFOS的萃取富集。     

典型全氟有机酸类化合物的样品前处理与分析方法研究进展

全氟辛烷磺酸（PFOS）和全氟辛烷羧酸（PFOA）是两种典型的全氟有机酸类化合物,也是全氟化合物（PFCs）前体物的最终降解产物,具有肝毒性、胚胎毒性、生殖毒性、神经毒性,检出率最高。在各种被污染的介质中,PFOS和PFOA含量往往很低,基体复杂多样,快速高效的样品前处理技术成为测定的关键环节。目前,国际上对PFOS和PFOA的测定无统一标准,而我国关于PFCs的分析研究落后于国际发展水平。该文介绍了PFOS和PFOA的特性,系统总结和评述了前处理技术（液液萃取、固相萃取、固相微萃取、超声萃取和QuEChERS法）及分析方法（色谱-质谱方法、光谱法、酶联免疫法和电化学法）,以期为PFOS和PFOA的分析监测及标准制定提供参考。     

溶胶-凝胶技术制备毛细管硅胶整体柱及其应用

采用溶胶-凝胶技术合成硅胶整体柱，研究了不同反应物配比对制备毛细管硅胶整体柱的影响，合成了具有高机械强度和化学稳定性的毛细管硅胶整体柱。通过十八烷基修饰得到反相固定相。考察了电渗流行为和电色谱性能。3种芳香胺和4种苯同系物可达到基线分离，柱效高达159000N／m。     

高效液相色谱-串联质谱联用测定人血液中的全氟化合物

采用HPLC-ESI-MS/MS联用技术,建立了分析血样中9种全氟化合物(PFCs)的方法.以13C4标记的PFOS (MPFOS)作为内标物.以C18反相柱为分析柱,甲醇、醋酸铵为梯度洗脱淋洗液,9种分析物包括全氟己烷磺酸(PFHxS)、全氟庚酸(PFHpA)、全氟辛酸 (PFOA)、全氟辛烷磺酸(PFOS)、全氟壬酸(PFNA)、全氟癸酸(PFDA)、全氟十一酸(PFUnDA)、全氟十二酸(PFDoDA)和全氟十四酸(PFTA),在15 min内即可达到良好的分离.在血样前处理中,采用MTBE液-液萃取和固相萃取相结合的方法,进一步净化样品以延长色谱柱寿命;比较了4种固相萃取小柱对全氟化合物的萃取性能,最终选定HLB柱(Waters).本研究还讨论了两种C18反相柱Acclaim 120(50 mm×4.6 mm, 3 μm)和Acclaim120 (250 mm×4.6 mm, 5 μm)(Dionex) 对PFCs的分析性能,在本实验条件下,两种色谱柱具有相似的分离性能及检出限,线性范围在0.1～50 μg/L之间 (r≥0.9957);对于血液样品该方法的检出限在0.03～0.8 μg/L之间.本研究将该方法成功地应用于血样实际样品中全氟化合物的测定,加标回收除PFTA较低外,其它化合物均在74.2%～118.1%之间.     

金纳米粒子修饰毛细管硅胶整体柱的制备及其电色谱性能研究

通过毛细管硅胶整体柱表面修饰十八烷基硫醇金纳米粒子,制备了一种新型毛细管电色谱固定相.制备金纳米粒子修饰整体柱时,采用溶胶-凝胶法制备毛细管硅胶整体柱,并在其表面化学修饰3-巯基丙基三甲氧基硅烷;通过巯基基团固载金纳米粒子于整体柱上,再共价键合十八烷基硫醇于金纳米粒子表面.以甲苯为探针,对理论塔板高度与流动相线速度之间...     

纺织品中全氟辛酸及全氟辛磺酰基化合物的气相色谱-μECD测试方法

建立了超声波辅助萃取-气相色谱-微电子捕获检测器测定纺织品中全氟辛酸(PFOA)及全氟辛磺酰基化合物(PFOS)的方法。通过单因子选择实验、正交实验等方法建立了纺织品中PFOA和PFOS的超声波萃取方法和PFOA的衍生反应条件。并采用加大流速和降低温度的方法,实现了3种PFOA和PFOS混合物的气相色谱分离及测试。方法的检测限为0.00591~0.02319μg/g;精密度为2.1%~9.7%;加标回收率为92.2%~101.9%。方法适用于纺织品中痕量PFOA和PFOS的监测分析。     

丙基脲硅胶毛细管整体柱的制备及性能研究

采用溶胶-凝胶技术在毛细管中原位合成硅胶整体柱,通过表面化学修饰技术制备了极性的丙基脲硅胶整体柱.对所制备的整体柱柱性能进行了评价,考察了极性物质在该整体柱上的保留行为,并对其可能的保留机理进行了探讨.研究表明,该柱在亲水作用电色谱模式下能有效分离苯酚类极性小分子化合物.     

溶胶-凝胶法制备毛细管硅胶整体柱的研究进展

毛细管硅胶整体柱作为一种新型的分离介质,在色谱领域显示出了强大的生命力。本评述介绍了溶胶-凝胶法制备毛细管硅胶整体柱的方法,重点分析了溶胶-凝胶法制备毛细管硅胶整体柱的影响因素,总结了近几年毛细管硅胶整体柱在高效液相色谱和电色谱中的应用。     

全氟辛酸和全氟辛烷磺酸人体暴露途径解析及其污染控制技术*

全氟辛酸（PFOA）和全氟辛烷磺酸（PFOS）是人工合成全氟化合物的典型代表。近年来,大量的环境调查数据表明它们普遍存在于多种环境介质、生物体甚至人体中,呈现出全球分布的态势,具有环境持久性和生物富集性,对人体健康存在潜在的危害,已成为一类新的环境持久性有机污染物而引起人们广泛的关注。本文介绍了PFOA和PFOS的环境来源和传输途径,解析了人体暴露的三种主要途径以及在食物、饮用水和空气/灰尘中的污染现状,并就围绕着它们所开展的污染控制技术方面的研究进行了评述。在此基础上,通过分析目前研究中所存在的问题,对今后的发展方向和研究重点进行了展望。     

液相色谱-串联质谱法快速测定电子电气产品中全氟辛酸和全氟辛烷磺酸

建立了液相色谱-串联质谱法快速测定电子电气产品中全氟辛酸(PFOA)和全氟辛烷磺酸(PFOS)的分析方法。采用加速溶剂萃取提取样品中PFOA和PFOS,二氯甲烷作溶剂,外标法定量,LC-MS/MS分析时间1 m in。电子电气产品中PFOS不同加标质量分数(0.25,0.75和1.25 mg/kg)的平均回收率分别为:91.6%、92.8%和94.7%;PFOA不同加标质量分数(0.50,1.25和2.25 mg/kg)的平均回收率分别为:90.1%、91.5%和93.4%;PFOS和PFOA测定的相对标准偏差分别为2.8%~3.3%和4.2%~4.9%。测定了金属框架涂层和氟聚合物材料中PFOS和PFOA的含量,PFOS含量分别为16μg/m2和0.89%,PFOA未检出     

溶胶-凝胶杂化整体柱修饰及在多环芳烃检测中的应用

利用点击反应对含叠氮基的溶胶-凝胶整体柱进行了表面修饰,制备了C₆-硅胶杂化整体萃取柱。实验以多环芳烃为分析对象,考察了制备和修饰条件对萃取效率的影响,在优化的条件下,新制备的整体柱对萘、菲、芘和苯并[a]芘的萃取富集倍数分别达到95.9、114.2、103.2和57.8。萃取实验的日内和日间精密度(RSD)分别小于5.5%(n=8)和7.3%(n=10)。建立的管内固相微萃取-高效液相色谱检测16种常见多环芳烃方法的检出限(S/N=3)达到0.08~3.72 μg/L,定量限(S/N=10)达到0.26~12.40 μg/L。土壤中多环芳烃分析的加标回收率为82.4%~110.6%, RSD为2.6%~7.9%(n=3)。与美国国家环境保护局检测土壤中多环芳烃的方法比较,结果一致,准确性高。实验表明,该方法萃取效率高,灵敏可靠,操作简便,重现性好,可满足土壤等样品中痕量多环芳烃检测的要求。     

纤维素键合型手性整体柱的制备及其在快速手性分离中的应用

采用N-丙烯酰琥珀酰亚胺(NAS)为基质单体,乙二醇二甲基丙烯酸酯(EDMA)为交联剂,原位聚合制备聚(NAS-co-EDMA)毛细管整体柱,并通过化学键合法将自合成的纤维素-三(4-甲基苯甲酸酯)(CTMB)共价键合到整体柱上,制备用于快速手性分离的纤维素键合型手性整体柱.优化了整体柱制备和衍生化条件;通过对固定相红...     

A Silica Monolithic Column with Chemically Bonded l-Pipecolic Acid as Chiral Stationary Phase for Enantiomeric Separation of Dansyl Amino Acids by CEC–MS

A silica monolithic column chemically modified with l-pipecolic acid as chiral stationary phase has been developed for chiral separation of dansyl amino acids by capillary electrochromatography–mass spectrometry (CEC–MS). The monolithic column was prepared by a sol–gel process and subsequent chemical modification by l-pipecolic acid as chiral selector with 3-glycidoxypropyltrimethoxysilane as spacer. Interestingly, it was found that the l-pipecolic acid-modified monolithic column can hold copper(II) ions tightly after loading Cu(II) ions during column preparation and conditioning and allows CEC separation to be conducted based on chiral ligand exchange with MS detection by a mobile phase without copper ions. It has been demonstrated that the chiral monolithic column operates well for enantioseparation of several dansyl amino acids by CEC–MS.

     

微流控芯片分析系统中硅胶整体柱和膜滤复合预处理单元的构建

以改性C18反相硅胶整体柱为微流控芯片分析系统中固相萃取介质材料, 构建不同功能单元的样品预处理微分析系统, 实现了血清样品中痕量盐酸多巴酚丁胺的富集. 初步构建了单一改性硅胶微柱固相萃取预处理单元, 测试得到了改性硅胶整体柱对血清中痕量盐酸多巴酚丁胺的平均富集倍数为77.2, RSD为12.35％. 为了提高测试的精密度, 进而设计含膜复合式预处理芯片, 探讨了不同预处理单元对血清样品中痕量盐酸多巴酚丁胺富集效率的影响, 优化设计了外接式硅胶整体柱-亲和膜微芯片固相萃取预处理单元, 复合式的反相硅胶整体柱对血清中微量盐酸多巴酚丁胺的平均富集倍数提高到89.4, RSD为4.37％. 结果显示了该预处理单元在血清中痕量药物富集的可行性和有效性.     

Enantioseparation on cellulose dimethylphenylcarbamate-modified zirconia monolithic columns by reversed-phase capillary electrochromatography

This work reports the preparation of monolithic zirconia chiral columns for separation of enantiomeric compounds by capillary electrochromatography (CEC). Using sol–gel technology, a porous monolith having interconnected globular-like structure with through-pores is synthesized in the capillary column as a first step in the synthesis of monolithic zirconia chiral capillary columns. In the second step, the surface of the monolith is modified by coating with cellulose tris(3,5-dimethylphenylcarbamate) (CDMPC) as the chiral stationary phase to obtain a chiral column (CDMPCZM). The process of the preparation of the zirconia monolithic capillary column was investigated by varying the concentrations of the components of the sol solution including polyethylene glycol, water and acetic acid. CDMPCZM is mechanically stable and no bubble formation was detected with the applied current of up to 30 μA. The enantioseparation behavior of the CDMPCZM columns was investigated by separating a set of 10 representative chiral compounds by varying the applied voltage and pH and organic composition of the aqueous organic mobile phases.     

胃蛋白酶亲和有机聚合物毛细管整体柱的制备及性能考察

以热引发原位聚合方法制备了聚（甲基丙烯酸缩水甘油酯（glycidyl methacrylate,GMA）-乙二醇二甲基丙烯酸酯（ethyleneglycol dimethacrylate,EDMA））毛细管整体柱,对整体柱的性能进行了表征。结果表明,柱内部结构均匀、渗透性好;整体柱能够实现苯等中性小分子化合物的分离,具有反相色谱特征,重现性和稳定性良好。利用整体柱环氧基团的活性,采用间接法,以戊二醛为连接臂制备胃蛋白酶亲和手性整体柱。在毛细管电色谱模式下进行了柱分离性能研究,并对缓冲液pH值和运行电压等分离条件进行了考察。结果表明,亲和整体柱对4种碱性手性药物（奈福泮、氨氯地平、西酞普兰、扑尔敏）有拆分效果,奈福泮、氨氯地平、西酞普兰能达到基线分离。本文为蛋白质亲和毛细管电色谱整体柱的制备和应用提供了新的思路和方法。     

Cyclodextrin-modified monolithic columns for resolving dansyl amino acid enantiomers and positional isomers by capillary electrochromatography

We describe beta- and gamma-cyclodextrins (beta- and gamma-CD)-modified monolithic columns prepared by sol-gel process and chemical modifications. The monolithic silica column was fabricated inside a fused-silica capillary with 100 microm inner diameter by sol-gel process. The monolithic silica matrix was chemically modified chiral selectors of beta- or gamma-CDs with a spacer of 3-glycidoxypropyltrimethoxysilane by on-column reactions. Gamma-CD-modified monolithic column has successfully been applied for the separation of dansyl amino acid enantiomers. Beta-CD-modified monolithic column has been used for the separation of the positional isomers of o-, m-, and p-cresols and the enantioseparation of racemates of benzoin and several dansyl amino acids by capillary electrochromatography, respectively. For the separation of neutral positional isomers, a positive electric field was applied. However, for the separation of negatively charged analytes, a negative electric field was applied at the inlet of column. The separation efficiency of 5.0 x 10(4) theoretical plates/m for dansyl-L-threonine was obtained at electric field strength of -300 V/cm in the mobile phase of 50 mM 2-(N-morpholino)ethanesulfonic acid (MES)-Tris/methanol (70/30) buffer at pH 7.0. L-enantiomers were eluted as the first peak. Scanning electron micrograph showed that monolithic columns have the morphology of continuous skeleton and large through-pores.     

Preparation of high efficiency and highly retentive monolithic silica capillary columns for reversed-phase chromatography by chemical modification by polymerization of octadecyl methacrylate

High efficiency and highly retentive monolithic silica capillary columns were obtained by polymerization of octadecyl methacrylate using alpha,alpha'-azobis-isobutyronitrile (AIBN) as a free radical initiator. Hybrid type monolithic silica columns (25 cm total length x 200 microm I.D.) prepared from a mixture of tetramethoxysilane and methyltrimethoxysilane were used as a support. The effects of the monomer and the radical initiator concentrations in the reaction mixture were examined. The performance of the columns was tested in terms of column efficiency and retention behavior by using alkylbenzenes and a few other compounds as solutes and compared with that of hybrid monolithic silica columns modified with octadecylsilyl-(N,N-diethylamino)silane (ODS-DEA). Highly retentive monolithic silica columns were obtained by polymerization at high monomer concentrations. Although a decrease in column efficiency was observed with the increase in the monomer concentration in a feed mixture, an improvement in efficiency was achieved (a plate height value lower than 10 microm) by increasing an initiator concentration without significant variations in column retention properties. Results obtained by polymerization using other monomers are also presented to demonstrate the applicability of the preparation method.