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1.
反相离子对色谱法测定硫代硫酸根和碘离子的研究   总被引:4,自引:0,他引:4  
张晓彤  云自厚 《色谱》1997,15(1):57-59
首次利用S2O2-3和I-与Hg-EDTA二元络合物通过柱前衍生形成EDTA-Hg-S2O3和EDTA-Hg-I两种三元络合物的方法,实现了对S2O2-3和I-的间接反相离子对色谱分离和紫外检测。在ZorbaxODS柱上,用甲醇∶水=23∶77作流动相,内含对离子TBA+3.0mmol/L,EDTA1.0mmol/L,NaNO32.0mmol/L和缓冲剂KH2PO4-Na2HPO4(pH7.0),紫外254nm检测。S2O2-3和I-的最小检出限分别为61.1ng和37.6ng。方法简便,选择性好。  相似文献   

2.
毛细管胶束电动色谱法测定夏枯草中两种有效成分   总被引:12,自引:0,他引:12  
建立了毛细管胶束电动色谱法(MEKC)同时分离和测定夏枯草中齐墩果酸和熊果酸异构体含量的新方法。以15mmol/L磷酸氢二钠(Na2HPO4)、15mmol/L硼砂(Na2B4O7)、10mmol/L十二烷基硫酸钠(SDS)、5%(V/V)乙醇的缓冲溶液作为运行电解质溶液,在20min实现了齐墩果酸和熊果酸的基线分离。同时也研究了SDS浓度和有机溶剂(乙醇)浓度对待测物质分离的影响。研究了不同提取  相似文献   

3.
李萍  于泓  崔凌飞  关良智  刘双全 《色谱》1998,16(1):65-67
首先用碱熔融法分解试样,然后加抗坏血酸将试液中的Fe3+还原为Fe2+,再用离子色谱法测定试液中的Fe2+,Mg2+和Ca2+。采用Shim-packIC-Cl阳离子交换柱分离样品离子,以0.25mmol/L乙二胺-0.50mmol/L柠檬酸(pH4.50)为流动相,以CDD-6A电导检测器检测,使被测组分得到满意的分离和检测。Fe,Mg和Ca的加标回收率均在90%以上。测定结果与原子吸收光谱法测定结果相近。  相似文献   

4.
王志  孙亦梁  王丹丹 《色谱》1997,15(5):378-380
 研究了同分异构体药物头孢Ⅳ号和氨苄青霉素及其目标生物合成前体三肽D-苯丙氨酸-L-半胱氨酸-D-缬氨酸、L-苯丙氨酸-L-半胱氨酸-D-缬氨酸的毛细管区带电泳分离。结果表明,采用含12mmol/L二甲基β-环糊精(DM-β-CD)的50mmol/LTris-H3PO4缓冲溶液(pH2.3)既可将头孢Ⅳ号和氨苄青霉素分离,又可将D-苯丙氨酸-L-半胱氨酸-D-缬氨酸、L-苯丙氨酸-L-半胱氨酸-D-缬氨酸分离。  相似文献   

5.
研究了同分异构体药物头孢Ⅳ号和氨苄青霉素及其目标生物合成前体三肽D-苯丙氨酸-L-半胱氨酸-D-缬氨酸、L-苯丙氨酸-L-半胱氨酸-D-缬氨酸的毛细管区带电泳分离。结果表明,采用含12mmol/L二甲基β-环糊精(DM-β-CD)的50mmol/LTris-H3PO4缓冲溶液(pH2.3)既可将头孢Ⅳ号和氨苄青霉素分离,又可将D-苯丙氨酸-L-半胱氨酸-D-缬氨酸、L-苯丙氨酸-L-半胱氨酸-D-缬氨酸分离。  相似文献   

6.
本文研究了新水溶性5,10,15,20-四(4-甲氧基-3-磺酸苯基)卟啉[T(4-MOP)PS4]的反相高效液相色谱(HPLC)分离条件。采用ShimpackPREP-ODS半制备色谱柱,用含有10mmol/L四乙基碘化铵的乙腈-水(体积比25:75)为流动相,流速18mL/min,于418nm波长下检测。[T(4-MOP)PS4]与合成中生成的杂质组分完全分离。经此制备的卟啉纯度高,已成功地应用于自来水样中微量钴、锌、铜离子的HPLC测定中。  相似文献   

7.
用反相高效液相色谱法分离和测定丁烯二酸的顺反异构体   总被引:7,自引:0,他引:7  
建立了分离和测定丁烯二酸的2个异构体-顺丁烯二酸和反丁烯二酸的反相高效液相色谱法。以Shim-pack CLC-ODS柱为分析柱,以甲醇-水(体积比5:2),用磷酸调至pH3.0)为流动相,流速0.7mL/min,检测波长为220nm,外标法定量。顺、反丁烯二酸的检出限分别为0.10和0.075mg/L(S/N=2);相对标准偏差分别为0.47%和0.54%(n=3)。二者的线性范围均为10~60  相似文献   

8.
新显色剂5,10,15,20-四(3-溴-4-磺酸苯基)卟啉,即T(3-BrP)PS_4,与Co(Ⅱ)、Zn(Ⅱ)、Cu(Ⅱ)离子生成螯合物,可在岛津CLCODS柱上用离子对反相高效液相色谱法(HPLC)分离。流动相为27+73的乙腈+水,内含20mmol/L的乙酸+乙酸钠缓冲液(pH6.0)和10mmol/L的四乙基碘化铵(TEA·I)。检测波长为420nm。应用于茶叶、桔皮和紫米中微量钴、锌,铜离子的测定中,结果满意。  相似文献   

9.
反相离子对高效液相色谱法分离和测定铝、镓和铟   总被引:9,自引:2,他引:7  
以芪-4,4‘-双(1-偶氮)-3,4-二羟基苯-2,2’-二磺酸铵(芪唑)为柱前衍生试剂,采用反相离子对高效液相色谱法分离和测定铝,镓和铟。在spherex C18柱上,用浓度为12mmol/L的SDS,浓度为20mmol/l pH3.5的AHc-NaAc的甲醇-水溶液作流动相,检测波长为506nm。  相似文献   

10.
系统地研究了碱性条件下(pH8~10.8)As3+,As5+,MA,DMA和AB等砷化合物在PRP-X100阴离子交换柱上的保留行为。用火焰原子吸收光谱(FAAS)测定从HPLC分离的砷化合物,即通过一根1m×0.23mmi.d.不锈钢毛细管,将HPLC柱出口与FAAS的雾化器连接起来,采用乙炔/空气火焰,在193.7nm处测定。具体研究了两个流动相(20mmol/LNH4HCO3和2.5mmol/L对-羟基苯甲酸-1.0mmol/L苯甲酸水溶液),并系统研究了pH值和缓冲液浓度对上述5个砷化合物的保留时间的影响,发现对于20mmol/LNH4HCO3体系,在pH8.7时,AB,As3+,DMA可以得到完全分离,通过梯度洗提(pH8.7到9.8,流速1.65mL/min),在15min内上述5个砷化合物可以得到良好分离;对于2.5mmol/L对-羟基苯甲酸-1.0mmol/L苯甲酸体系,在pH9.0及流速1.5mL/min时,可以在12min内将上述5个砷化合物分离。  相似文献   

11.
微柱液相色谱的研究进展   总被引:13,自引:0,他引:13  
介绍了微柱液相色谱(μ-LC)。从理论上简单讨论了μ-LC的柱特性、色谱洗脱效应和柱外效应等一系列问题,综述了μ-LC的柱技术的最新进展,讨论了μ-LC对仪器和附件的要求,特别是微流量输液和检测技术,还探讨了μ-LC与多维色谱、质谱等技术的联用。  相似文献   

12.
建立了反向模式-强阳离子交换-反向模式(Reversed phase-strong cation exchange-reversed phase)二维色谱平台测定人血浆中甲氨蝶呤浓度的方法。样品经三氯醋酸沉淀蛋白后,在ASTON C8一级柱(100 mm×4.6 mm,5μm)上完成初分离,通过六通阀切换,经ASTON SCX中间级(20 mm×4.6 mm,5μm)二次分离和储存,在SAC C8二级柱(100 mm×4.6 mm,5μm)上完成最后分离,并测定。一级柱流动相为10 mmol/L醋酸铵-乙腈(90∶10,V/V,以醋酸调至p H 3.8),流速为1.0 m L/min;中间级流动相为10 mmol/L H3PO4溶液(p H 3.0);二级柱流动相为50 mmol/L醋酸铵-乙腈(87∶13,V/V,以醋酸调至p H 5.2),流速为1.2 m L/min,检测波长306 nm。单次分析时间4 min,线性范围0.09~5.1μmol/L,检出限为0.005μmol/L,日内RSD小于1.8%,日间RSD小于3.5%,相对回收率99.1%~101.25%,绝对回收率85.7%~86.4%。本方法简便、准确,适合日常血药浓度监测和药代动力学研究。  相似文献   

13.
The present study described the preparation and application of a reversed-phase/zwitterionic/hydrophilic interaction liquid chromatography stationary phase, named as SIL-PS. The SIL-PS was prepared through a four-step reaction, chemical bonding, nucleophilic addition, SN1 substitution, and sulfonation on the silica matrix. It was featured with C12 alkyl chain, quaternary ammonium, tertiary amine, and sulfonate groups. After SIL-PS was packed into the stainless steel column (150?× 2.1 mm i.d.), chromatographic parameters, including acetonitrile content, pH, and ionic strength of the mobile phase, and the column temperature, were systematically investigated to study the retention mechanism. Electrostatic adsorptive/repulsive, partition, and hydrogen-bonding interactions were demonstrated to contribute to the retention. The stability of the SIL-PS was satisfactory, with relative standard deviations of retention factors of 1.93, 2.08, and 1.90% for loxoprofen, adenosine, and liquiritin, respectively. Additionally, to investigate the separation selectivity, the non-steroidal anti-inflammatory drugs, nucleobases/nucleotides, and alkaloids/glycosides were separated; the HPLC fingerprinting of the Cortex phellodendri extract was also conducted, and the separation performance was superior to that of the C18 column in terms of peak shape, resolution, and analytical time. The results revealed that the prepared SIL-PS possessed multifunctionalities for multiretention and could be promising for complicated samples.  相似文献   

14.
Alkaloids are a widespread group of basic compounds in herbal medicines and have attracted great interest due to various pharmaceutical activities and desirable druggability. Their distinctive structures make chromatographic separation fairly difficult. Peak tailing, poor resolution, and inferior column‐to‐column reproducibility are common obstacles to overcome. In order to provide a valuable reference, the methodologies and/or strategies on liquid chromatographic separation of alkaloids in herbal medicines proposed from 2012 to 2019 are thoroughly summarized.  相似文献   

15.
Summary In micellar liquid chromatography (MLC), the hydrophobicity of a compound is the predominant factor in its retention and interaction with micelles. A non-linear empirical model can describe the dependence between the retention factor (logk) in MLC and the logarithm of partition coefficients octanol-water (logP). An algorithm based on such a model has been used to makelogP predictions. Retention data for series of neutral compounds eluted with different mobile phases and alkyl-bonded stationary phases have been used to test the predictive ability of the algorithm. The results of this approach are compared with those obtained from automatic computational software packages.  相似文献   

16.
《Analytical letters》2012,45(6):411-414
Abstract

A Thermal Energy Analyzer has been interfaced to a high performance liquid chromatograph. The hplc-TEA system can be used for analysis of nanogram amounts of N-nitroso compounds.  相似文献   

17.
Summary An HPLC procedure is described for the determination of caffeine in pharmaceutical preparations. A Spherisorb octadecylsilane ODS-2 C18 analytical column and spectrophotometric detection at 273 nm were used. The chromatographic behaviour of caffeine with different micellar eluents containing sodium dodecyl sulphate (SDS) is described. The determination of caffeine in pharmaceutical preparations was performed by use of a mobile phase containing 0.05 M sodium dodecylsulphate (SDS) and 1.5% propanol at pH7. At a 6.0 g mL–1 concentration level the peak area and peak height repeatability were 2.6 and 2.4%, respectively. The application of the proposed method to the analysis of five pharmaceutical formulations, using peak heights as the dependent variable, gave recoveries between 85 and 104% of the values declared by the manufacturers. The proposed procedure for the determination of caffeine is rapid (15 min per sample), reliable and free from interferences.  相似文献   

18.
考察了烷基酚聚氧乙烯醚在反相色谱、正相键合色谱、硅胶吸附色谱、体积排阻色谱4种不同液相色谱分离模式中的分离效果,分别采用Kromasil C_(18)(250 mm× 4.6 mm,5 μm)、Agilent ZORBAX NH2(250 mm× 4.6 mm,5 μm)、Waters Spherisorb S3W(150 mm×2.0 mm,3 μm)和Shodex MSpak GF-310 2D(150 mm×2.0 mm,5 μm)色谱柱,以225 nm为紫外检测波长,对不同液相色谱分离模式的流动相组成、梯度洗脱条件、柱温、流速等进行了优化,并对烷基酚聚氧乙烯醚在不同液相色谱分离模式中的保留机理进行了初步探讨.结果表明,正相键合色谱实现了烷基酚聚氧乙烯醚的最佳分离;硅胶吸附色谱和体积排阻色谱的分离效果较正相键合色谱稍差.  相似文献   

19.
Summary This paper presents the, chromatographic retention of Co(II), Ni(II) and Cu(II) as diethyldithiocarbamate complexes in the presence of hexadecyltrimethylammonium bromide/ethanol/water systems, as mobile phase, by reversed phase high performance liquid chromatography. The presence of an organic modifier reduces the retention times and improves the efficiency. In order to evaluate the interaction between the metal complexes and the mixed micellar system the values of solute binding constants are calculated in, two ways: a) Arunyanart and Cline-Love's treatment and b) multiple regression analysis taking account of the ethanol percentages.  相似文献   

20.
Summary The internal cyclization of a new phenyldiazene liquid crystal (called A), with an activated methylene group in theortho position to the diazo linkage, has been studied. The kinetics of cyclization were studied at different temperatures and followed by HPLC. Separations were performed on a 30 cm×0.4 cm silica column withn-heptane-tetrahydrofuran-acetonitrile, 190∶20∶5 (v/v), as mobile phase. The Van't Hoff plot (of ln reaction constantk against 1000/T) gives a mean activation energy of 101.3±2.1 kJ mol−1. The analytical properties of A and the final compound B during the decomposition were investigated by gas chromatography on home-made glass capillary columns coated with A. The retention times of the solutes tested became constant when the B/A ratio reached 5, which corresponds to 83% cyclization. The nematic phase of B has interesting properties enabling the separation of the isomers of decalin, the positional isomers of diethylbenzenes and phenols, and some polyaromatic hydrocarbons and their derivatives.  相似文献   

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