毛细管气相色谱法定量测定氮酮

对毛细管柱定量测定氮酮的操作条件进行了探索 选择了以DB 1型石英毛细管色谱柱φ0.53mm×30m,宽口径进样口不分流进样,FID检测器,压力程序升压,柱温箱程序升温,进样量1μL的色谱条件,对氮酮样品进行检测,各组分分离良好 定量检测结果:线性范围为20μg～0.2μg,线性方程:Y=6.0888×106+1.41573×107X,r=0.99997,,加标回收率为100.25%,仪器精密度RSD=0.45%,满足定量分析的要求     

薄层色谱法分析环十五内酯

环十五内酯是一种珍贵的大环麝香类香料,对其定性和定量分析通常使用气相色谱法(GC)和气相色谱一质谱联用法(GC—MS)。但对于以15—羟基十五烷酸为底物经脂肪酶催化合成的环十五内酯,由于产物中残留长链的脂肪酸和脂肪酶。采用溶剂萃取分离有一定难度,尤其是对反应的跟踪测定,GC和GC—MS难以应用。薄层色谱法(TLC)能定性分析环十五内酯。但展开剂、显色剂等的影响没有得到关注。限制了TLC的应用范围。本文建立了一种为酶催化合成环十五内酯提供快速、简便的TLC分析方法。     

微量MOCA快速中间控制测定的薄层色谱法

聚醚-聚丁二烯共聚物弹性体的缩聚过程中,存在着残留微量扩链剂MOCA[4.4′-亚甲基双(2-氯苯胺)]。在多个样品平衡试验中,对它进行快速中间控制对比测定是制备过程的必要环节,参考C.Fenimore实验,以TLC板用等量点样量不同径度地点样于板上,经展开到适当距离后会集束于相同的径度。由此推想此时TLC板的单位面积具有相同的负荷量。本文用简易的TLC法在没有特殊设备下经多次探索其灵敏度和重复性良好。     

薄层色谱法在定量分析中的应用

对薄层色谱的定量方法，即目测法，斑点面积法，洗脱法及扫描法作了简要介绍；对1998-2000年薄层色谱法在医药，食品及其他领域定量分析中的应用进行了综述。     

酰胺反应的薄层色谱法分析

用薄层色谱法监测了二氯乙酰氯与相应的胺合成二氯乙酰胺的反应过程,方法操作简便、快速、准确。     

薄层色谱法测定蕃茄酱中的蕃茄红素

蕃茄红素是蕃茄的特有色素,其含量是蕃茄酱的重要质量指标。现在通用的测定方法为分光光度法,其不仅操作繁烦,而且往往因分离不完全引起偏差。采用薄层色谱法(苯-石油醚为展开剂)可将蕃茄红素(R_t=0.44)、胡罗卜素(R_t=0.66)及几乎停留在原点的其它色素分开,并以双波长薄层扫描测定蕃茄红素的含量。     

薄层色谱法半定量分析抑制光合作用的除草剂的残留

我们采用希尔反应对9种能抑制光合作用的除草剂在薄层色谱(TLC)上的定位及半定量进行了探索。除草剂在薄层板上展开后,喷有小麦嫩叶离体的叶绿体和2,6-二氯酚靛酚钠盐的混合溶液在光照射下,在板上无除草剂的部位水分解,放出氧。2,6-二氯酚靛酚钠盐被还原后,颜色由蓝色变成无色,而板上有除草剂的部位抑制了希尔反应,不能产生氧气。因此,在薄层板上显色的背景是绿色,除草剂的斑点是蓝灰色,据此可以检测除草剂的残留。     

薄层色谱法分析味精废液中氨基酸

发酵法制味精是一个复杂的生化过程。在生成谷氨酸的同时有其它氨基酸或多或少的生成。虽TLC用于氨基酸分离的论文甚多,但用之于味精废液中氨基酸的分析却并不多见。本文用TLC方法以湖南某市味精厂废液作样品,讨论介绍了TLC用于味精废液中氨基酸分析的具体方法。 实验部分 (一)味精废液的取样和处理 1.随机取废液一瓶,离心除去沉淀,加入酒精杀菌、密封。 2.取50ml废液中速离心半小时,取上清液倒入732型阳离子H型交换树脂中浸泡10min,之后     

薄层色谱法检测槟榔中糖精含量

在湖南长沙、湘潭等地素有嚼食槟榔的传统习惯,每年要消耗槟榔干果数10t.槟榔在精制过程中,常加入糖精以增加甜度.作为化工产品的糖精,毫无营养价值,对人的致癌性目前尚有争论.我国食品中糖精限量一般为不超过0.159·kg~(-1),故检测槟榔中糖精含量有卫生学意义.糖精的测定方法目前有薄层色谱法、电极法、比色法、紫外光谱法、高压液相色谱法等.但是较简便的方法还是首推薄层色谱法,该法是测定食品中糖精的国标法.我们在已有工作的基础上,参照国标法,选用硅胶GF_(254)作吸附剂,测定了210件槟榔样品中糖精含量,结果满意.     

色谱法研究杂多酸Ⅶ: 杂多酸薄层色谱分离及测定

本文研究了杂多酸的TBA及无机阳离子两种不同类型盐的薄层色谱特性,探讨了实验条件对两种类型杂多酸盐薄层色谱分离的影响, 选择合适的条件可使杂多酸盐各组分得到分离。以薄层色谱扫描仪对分离后的样品斑点进行扫描测定, 得到满意的结果。     

STUDY ON THE DETERMINATION OF TRACE BISMUTH(Ⅲ) BY THIN-LAYER RESIN PHASE SPECTROPHOTOMETRY

In this paper, a new thin-layer ion-exchange resin phase analytical method is introduced. It is based on that, the bismuthous cation can associate with iodic anions, so as to formed an anioncomplex [BiI-4] in a strong acidic environments. This anion complex can also exchanges with a weaker anions on the surface active site of anion exchange resin, so that a [R+] [BiI-4] solid phase binary associational system is produced. Owing to the solid system is a great many dispersive particulates, it can be pressed to a thin-layer by press tools of the so called "thin-layer resin phase"or "resin phase ", and using this solid association system spectrophotometry for the determination of trace metals. So it can increase the analytical sensitivity. This association system exhibits maximum absorbance at 460nm, and obeys Beer's law over the concentration range 0. 01ug/ml～1.20ug/ml of bismuthous(Ⅲ). It has a molar absorptivity of 7.1 ×105 [L/mol cm]. It indicated the resin phase spectrophotometry is a sensitive analytical method for trace bismuthous. It is 18 times higher than routine aqueous spectrophotometry. The relative standard deviations is 1.82% (n=6) for the measurements of 0. 5ug/ml Bi(Ⅲ). The detection limit of Bismuthous(Ⅲ) is 1.4 ×10-8mol/L. The method has applied to the analysis Bi(Ⅲ) in environmental water samples.     

STUDY ON THE DETERMINATION OF TRACE BISMUTH(III) BY THIN-LAYER RESIN PHASE SPECTROPHOTOMETRY

1.INTRODUCTIONThinlayerresinphasespectrophotometryisanewanalyticalmethodinthefieldofspectrophotometricanalysis;ittakesitssourceattheliquid-liquidextractiontechniquesincombinedwithclassicalspectrophotometricanalysis.Thesubstanceofproposedmethodisaccordingtounderprinciplesthatthetargetmetalionswasassociatedwithsomeligandsinaqueousphase,thentoformedaternaryormulticomponentcomplexions,suchasanioncomplexes.Aftertheassociationreactionwasfinished,thecomplexionswillassociatedwithaion-exchangeresin…     

A novel approach to the qualitative and quantitative assay of HPTLC plates: Second and fourth derivative recording of spectrophotodensitograms

One of the limitations due to lack of resolution for a given pair of analytes in TLC or HPTLC is the need to optimize the system. In Practice this requires time, rerunning of the sample in different developing solvents, and a great deal of expertise on the part of the analyst. In our experience, application of first and second derivative recording techniques to HPTLC facilitates and speeds the whole process, permitting qualitative and quantitative assay of most unresolved spots. Consequently, we have now extended our instrumental capabilities to fourth derivative measurements. For this purpose, we have added a homemade electronic unit in series with the one previously used for first and second order derivatives. Thus, we have been able to evaluate the potential advantages of higher order derivatives for HPTLC analysis of unresolved components in various pharmaceutical products. A comparison of second and fourth order derivative measurements of seriously overlapping HPTLC components in a sample of preservatives used in the pharmaceutical industry suggests that the lower order derivatives might be a better choice in view of the higher accuracy and precision of the corresponding data. This is supported by the results of other applications, such as the assay of a commercial colorant, and a syrup formulation. The observed lack of precision of fourth order measurements stems from the fact that although the second and higher order derivatives produce narrower bandwidths, thus contributing to improved resolution, the signal to noise ratio decreases and satellite peak interactions increase, thus rendering correct discrimination of the fine structural detail of overlapping components more difficult.     

薄层扫描法测定银杏外种皮中白果酸含量

报道了一种简单、灵敏、准确测定银杏外种皮中白果酸含量的方法——薄层色谱扫描法。线性范围为1．0～5．0μg／点，纯品的相对标准偏差为1．29％(n=6)，平均回收率为99．7%，方法简便、重现性好。     

离子色谱法测定蔬菜硝酸盐含量

建立了化学抑制电导检测离子色谱法定性定量分析蔬菜硝酸盐含量的方法。阴离子分离柱DionexAS14柱(4mm×250mm),保护柱IonPacAG14(4mm×50mm)。流动相为1.7mmol.L-1NaHCO3,1.8mmol.L-1Na2CO3。流速1.2mL.min-1,自动连续再生抑制装置SRS-ULTRA4mm。线性范围为0.1~100.0mg.L-1,线性关系为0.9997,检出限为0.05mg.L-1。应用此法,测定了多种蔬菜硝酸盐含量。方法操作简单、快速、基体干扰少、灵敏、准确。     

脂肪和芳香磺酸盐的离子色谱分析方法研究

试用流动相与多维分离离子色谱法分析己烷磺酸、辛烷磺酸、十二烷基磺酸钠、十二烷基苯磺酸钠等磺酸盐,并将两种方法作了对比.流动相离子色谱法选用2mmol·L~(-1)四丁基氢氧化铵(TBAOH)作离子对试剂,乙腈作有机改进剂做梯度淋洗,并采用12.5mmol·L~(-1)H_2SO_4作再生液,电导检测.多维分离用电导检测,1.8mmol·L~(-1)Na_2CO_3/1.7mmol·L~(-1)NaHCO_3淋洗液做等浓度淋洗.该方法的检出限为0.75～11.50mg·L~(-1),线性范围为0.75～30mg·L~(-1),方法用于石油样品的分析得到满意结果.     

毛细管气相色谱法测定水中挥发性卤代烃

选择HP 1大口径厚液膜通用型熔融石英毛细管柱(30m×0.53mm×2.65μm),ECD检测器,吹扫 捕集法富集样品,研究了测定10种挥发性卤代烃的最佳色谱条件。结果表明,水样体积为5.00ml时,标准偏差<0.07μg·L-1,RSD<4.0%,加标回收率为94.0%～107.0%,10种物质的检出限在0.07～0.19μg·L-1之间。方法用于河水样品中的组分测定,结果满意。     

离子色谱法测定除锈剂中钼酸根

通过单纯形优化法选择测定MoO2-4的最佳色谱条件,淋洗液组成为4.866mmol·L-1Na2CO3＋1.5mmol·L-1 NaOH。同时采用该分析方法测定除锈剂(磷化剂)中的MoO2-4,得到了良好的重现性和线性,样品的回收丰大于95％。     

气相色谱法测定多泥沙水体中挥发性卤代烃

应用气相色谱-电子捕获检测器(ECD)检测法测定了多泥沙的黄河水样中挥发性卤代烃。用吹扫捕集法作试样预处理。为降低卤代烃在水溶液中的溶解度,采用了饱和氯化钠溶液作为专用电解质,因而也提高了方法的灵敏度,按优化的分析条件,对4种卤代烃作了试验。结果表明,四者分离良好,检出限在0.01~0.20μg.L-1之间。加标回收率在95.0%~103.0%之间。