两种色谱法对塑料食品包装袋中邻苯二甲酸酯类化合物的分析

建立了毛细管气相色谱和薄层色谱测定5种邻苯二甲酸酯类化合物（邻苯二甲酸二甲酯（DMP）、邻苯二甲酸二乙酯（DEP）、邻苯二甲酸二丁酯（DBP）、邻苯二甲酸二正辛酯（DOP）和邻苯二甲酸二（2．乙基己基）酯（DEHP））的方法。样品用乙醇浸泡，超声提取，0．5p．m滤膜过滤。进行气相色谱和薄层扫描分析。气相色谱回收率：88．85％-120．19％，精密度RSD为1．6％-3．2％，检出限DMP、DEP、DBP、DOP和DEHP分别为2．0、1．8、2．6、3．2和3．1ng，两种方法均样品用量少，分离效果好。区别在于前者灵敏度、回收率高，后者样品前处理简单、费用低。各有优势。     

薄层色谱法应用于N-乙基-对-薄荷烷-3-甲酰胺的分离和鉴别

研究了用薄层色谱法分离和鉴别在合成N-乙基-对-薄荷烷-3-甲酰胺中所得粗品的各组分。试验表明硅胶H(60型)为最佳吸附剂。敷有此吸附剂的薄层层析板经在110℃活化2 h,所用展开剂为以5与1之比混合的石油醚和丙酮混合溶剂,展开距离最少为14.00 cm,经展开后粗品中4组分得到很好的分离。展开层用碘铋化钾(KBI4)溶液和碱性高锰酸钾溶液喷洒即可清楚地观察到4个色斑,其Rf值依次为0.82,0.67,0.50和0.33,即Rf为0.33的色斑取下作元素分析,所得结果证明此组分即是N-乙基-对-薄荷烷-3-甲酰胺。     

参考JJF-1059对农药多残留分析国标方法NY/T761.1-2004的不确定度评价研究

参考JJF-1059<测量不确定度评定与表示>,对农药多残留分析国标方法NY/1761.1-2004(蔬菜和水果中有机磷、有机氯、拟除虫菊酯和氨基甲酸酯类农药多残留检测方法)进行了不确定度的评价研究.对黄瓜基质上的5种有机磷农药(敌敌畏,乐果,甲基对硫磷,毒死蜱,克线磷),应用国标NY/T761方法进行检测.从标准过程、质量称量过程、体积定容和样品处理过程等方面分析农药残留操作环节的不确定度.结果表明,不同农药或浓度水平之间扩展不确定度并没有显著差异,校准过程占整个不确定度的比重随着待测物浓度水平降低而显著提高.     

Behavior of peptides and computer-assisted optimization of peptides separations in a normal-phase thin-layer chromatography system with and without the addition of ionic liquid in the eluent

The addition of an ionic liquid into the mobile phase appeared to be useful in optimization of chromatographic separation of peptides. Different behavior of peptides in thin-layer chromatography (TLC) was observed after addition of 1-ethyl-3-methylimidazolium tetra fluoroborate to the eluent in comparison to the system without the ionic liquid. Nonlinear dependence of the retention coefficient, R(M), of peptides on the volume percentage of acetonitrile in the eluent was found in normal-phase TLC with and without immidazolium tetra fluoroborate in the mobile phase. In general, R(M) increased with increasing concentration of acetonitrile. In TLC systems without the ionic liquid, R(M) can be described well with a quadratic function. On the other hand, in a TLC system with an ionic liquid as the additive to the mobile phase, the retention behavior is better described with a third-degree polynomial function. The potential usefulness of ionic liquids for optimization of separation of peptides was demonstrated. Optimization of the separation conditions was supported by a commercially available computer program.     

TLC for pharmaceutical analysis in resource limited countries

This review article discusses the sustainability and robust advantages of planar chromatography that are critical to the successful performance of product quality assessments in resource limited areas including field applications. Because of the robustness and ease of use, the training required for successful performance of the high performance thin layer chromatography (HPTLC) assessments is much lower than that of other technologies with comparable reproducibility such as high performance liquid chromatography (HPLC). Some of the successful applications of planar chromatography in resource limited countries are presented. It should be noted that these planar chromatographic technologies have much lower plate counts and therefore separation power than column technologies such as HPLC and gas liquid chromatography (GLC). However in finished pharmaceutical products there are generally few active ingredients which are assessed making the HPTLC adequate for these analyses. In addition at this time there is a much wider array of detection technologies available for HPLC and GLC.     

计算机辅助一清片径向展开薄层色谱定性与定量方法初探

径向薄层色谱法（RTLC）是一种将样品呈圆形或环状点样,然后将展开剂从中心向外沿径向输送的薄层色谱方法。在一定的展开距离内,RTLC是一种分离快速、扩散小、不拖尾的高效分离和半制备方法。目前关于RTLC分离的报道较多,但对RTLC定性和定量的报道较少。该文采用自编程方式结合图像处理软件,实现RTLC图像数字化处理,形成RTLC数字化图谱,并对RTLC进行定性与定量方法学验证,建立了一清片RTLC定性与定量方法。辅助计算机技术,对一清片径向展开薄层色谱定性与定量方法进行初探。结果表明,该方法用于RTLC定性的可靠度较好,但用于RTLC的定量,仍有不足之处,这可能与实验环境条件等有关。通过搭载更好的分离和数据采集设备,RTLC会有适合的用武之地。计算机图像处理和自编程方法的结合给了RTLC和其他一些分析相关的技术广阔的发展前景。相信未来在计算机技术的辅助下,薄层色谱技术会迈上一个新的台阶。     

浸渍硅胶薄层色谱板分离钴和镍及数字图像分析法定量(英文)

Thin layer chromatography(TLC) of cobalt and nickel has been performed on silica gel layers induced with alkali mediated cellulose extract.A novel combination of 10% aqueous solutions of Tween-20 and potassium thiocyanate in 1∶1(v/v) was identified as the best mobile phase for the selective separation of Co2+from Ni2+on the impregnated Silica Gel G layers.The chromatographic characteristics of the cations were studied and the limits of detection as well as the limits of quantification for Co2+and Ni2+were determined.The quantitative estimation of the cations was achieved from the digital image analysis of respective chromatograms.The proposed quantitative method was successfully applied with 0-0.50% error for the determination of Co2+from Ni2+in spiked samples of bauxite,soil and rock containing common cations such as Al3+,Fe2+,Ti4+,Zn2+,Mn2+,Cu2+,Cr6+,Mg2+,etc.under the optimized chromatographic conditions.     

离子色谱-紫外检测法测定饲料中的胍基乙酸

通过对色谱柱、流动相洗脱、样品前处理等条件进行优化,建立了一种检测饲料中胍基乙酸含量的离子色谱法。在甲磺酸线性梯度洗脱条件下,样品经Dionex IonPacTMCS16阳离子交换柱分离,用紫外检测器于200 nm波长处进行检测。在0.5~200 mg/L范围内,中胍基乙酸色谱峰面积与质量浓度呈良好的线性关系(相关系数r2=0.999 9)。配合饲料和浓缩饲料中胍基乙酸的检出限为4.5 mg/kg、定量限为15 mg/kg,复合预混合饲料中胍基乙酸的检出限为9.0 mg/kg、定量限为30 mg/kg。该方法对添加量在15 mg/kg~60 g/kg范围内的禽用配合饲料、猪用配合饲料、浓缩饲料、复合预混合饲料中胍基乙酸的回收率均大于94%。该方法性能指标可满足饲料中胍基乙酸含量的检测需求。     

柱前衍生高效液相色谱法测定二乙醇胺脱氢产物亚氨基二乙酸和甘氨酸

以对甲苯磺酰氯(PTSC)为衍生剂,建立了柱前衍生高效液相色谱(HPLC)测定二乙醇胺脱氢产物中亚氨基二乙酸(IDA)和甘氨酸(Gly)含量的分析方法。IDA和Gly与衍生剂在碱性(pH 11)条件下于45℃反应15 min,进行柱前衍生,并利用高效液相色谱-质谱对衍生产物进行定性分析。衍生化产物采用VP-ODS色谱柱(200 mm×4.6 mm,5μm)分离,以0.03 mol/L醋酸铵溶液(pH 5.5)为流动相A、乙腈为流动相B(体积比为87∶13),进行等度洗脱,流速为1 mL/min,并采用配有紫外检测器的高效液相色谱仪测定,检测波长为235 nm。该法在IDA质量浓度为900~2 100 mg/L、Gly质量浓度为20~100 mg/L的范围内线性关系良好,相关系数(R2)均大于0.999。IDA和Gly的检出限(LOD)分别为0.089 7 mg/L和0.026 2 mg/L,加标回收率分别为98.7%~99.3%和98.0%~99.5%,相对标准偏差(RSD)分别为0.89%~1.23%和0.95%~1.11%(n=3)。该法具有反应条件温和、准确性高的特点,可用于工艺生产中IDA和Gly含量的测定。     

基于分子络合的分散液液微萃取与高效液相色谱联用检测环境水样中2种苯氧羧酸类除草剂

建立了基于分子络合的分散液液微萃取（DLLME）方法,以磷酸三丁酯为萃取剂,以甲醇为分散剂,与高效液相色谱联用检测了环境水样中麦草畏和2,4-二氯苯氧乙酸（2,4-D酸）2种苯氧羧酸类除草剂,对影响前处理效果的因素（包括水样的pH值、萃取剂的种类和体积、分散剂的种类和体积、反萃液的pH值、反萃液的体积和盐浓度等）进行了详细考察,在最佳萃取条件下（水样体积10 mL,水样的pH值为0~1.0、100 μL磷酸三丁酯萃取剂、1000 μL甲醇分散剂、0.01 mol/L的氢氧化钾反萃液的体积为80 μL）,2种苯氧羧酸类除草剂在0.50~1000 μg/L范围内具有良好的线性,相关系数不小于0.9985,麦草畏和2,4-D酸的检出限分别为0.44 μg/L和0.49 μg/L,富集倍数分别为85和90,在实际样品中的加标回收率为75.7%~104.0%。该方法基于分子络合反应机理,将新型萃取剂磷酸三丁酯应用于分散液液微萃取,与HPLC联用实现了麦草畏和2,4-D酸的富集与检测,为环境水样中苯氧羧酸类除草剂的检测提供了新的前处理方法。     

Evaluation of porous graphitic carbon as stationary phase for the analysis of fatty acid methyl esters by liquid chromatography

Summary Polyunsaturated fatty acids have been analysed as methyl esters by liquid chromatography on porous graphitic carbon and the results compared with those obtained on octadecyl bonded phases. Chromatographic behaviour on octadecyl bonded phases arises principally as a result of hydrophobic interactions with the bonded phase. Because the retention of analytes is greater on porous graphitic carbon than on octadecyl phases, organic mobile phases are required. When the number of double bonds is low (ca 1–3), the behaviour of porous graphitic carbon is similar to that of octadecyl bonded phases, but when this number increases stronger interactions with the flat surface of the graphite appear, resulting in new selectivity. These two ‘reversed-phase’ systems are considered complementary for separation of different fatty acid methyl esters. An additional advantage of porous graphitic carbon is that it enables isolation of hexadecartrienoic and hexadecadienoic acids, which are not available commercially.     

基于脂肪酸的漂浮液滴固化分散液液微萃取-高效液相色谱法联用测定酒类样品中的4-乙基苯酚和4-乙基愈创木酚

建立了基于脂肪酸的漂浮液滴固化分散液液微萃取（FA-DLLME-SFO）方法,与高效液相色谱联用检测了酒类样品中的4-乙基苯酚和4-乙基愈创木酚。该方法萃取时间仅需4 min,仅需脂肪酸、氨水和硫酸3种对环境友好的试剂。对影响方法萃取效率的因素（包括样品的体积、萃取剂的种类和用量、氨水和硫酸的体积以及盐的加入量）进行了详细的考察。在最佳萃取条件下（10 mL样品,100 μL辛酸萃取剂,110 μL 25%～28%（质量分数）的氨水,0.8 mL 98%（质量分数）的浓硫酸,3.0 g NaCl）,4-乙基苯酚和4-乙基愈创木酚在0.02～1.0 mg/L范围内呈良好的线性关系,相关系数分别为0.9997和0.9999,相对标准偏差（n=3）分别为6.2%和3.5%,检出限分别为6.33和5.81 μg/L,富集倍数分别为79和86。在啤酒和白葡萄酒样品中,加标回收率为81.4%～108.7%,相对标准偏差（n=3）小于8.9%。该方法简单、对环境友好,可用于酒类样品中4-乙基苯酚和4-乙基愈创木酚的检测。     

不粘锅涂层中全氟辛酸及其盐的气相色谱法测定

采用气相色谱建立了不粘锅涂层中全氟辛酸及其盐(PFOA)残留量的测定方法。样品用乙腈在175℃、10.3 MPa下用快速溶剂萃取仪萃取20 min;通过对衍生化试剂、用量、反应时间的优化,选用1∶20的乙酰氯-无水甲醇衍生化试剂。用HP-1毛细管柱(25 m×0.20 mm i.d.,0.33μm)分离,气相色谱/电子捕获检测器测定。PFOA的定量下限为5μg/kg。4个添加水平的平均回收率在96%~105%,相对标准偏差为1.81%~4.91%。