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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
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
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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
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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
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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
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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
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Wen‐Jing Zhao Xu‐Yan Chen Yu‐Qian Liu Ping Li Hui‐Jun Li 《Journal of separation science》2020,43(9-10):1755-1772
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
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L. Escuder-Gilabert Y. Martín-Biosca R. M. Villanueva-Camañas M. J. Medina-Hernández S. Sagrado 《Chromatographia》1999,50(5-6):325-332
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
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《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
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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
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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
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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
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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