Separation of Metalloporphyrins by TLC

JPC – Journal of Planar Chromatography – Modern TLC - Complexes of hydroxy- and alkyloxytetraphenylporphyrins with Cu (II), Zn (II), and Ni (II) have been prepared and their...     

糖类衍生物在毛细管区带电泳下的分离研究

以新合成的1-萘基-3-甲基-5-吡唑啉酮(NMP)为柱前衍生试剂,采用毛细管区带电泳模式考察并优化了糖类衍生物的分离条件。实验采用58.5cm×50μmi.d.毛细管(有效柱长50cm),55mmol/L硼酸盐缓冲溶液(pH9.46),柱温20℃,分离电压22kV,进样10s,在不加任何添加剂的情况下,高效、快速地实现了9种糖的基线分离,并在最优化条件下进行了唐古特白刺实际样品的分离分析,结果令人满意。     

Quantitative Separation of Pd(II) by TLC of Metal Ions on Cerium (IV) Antimonate

Abstract

A quantitative TLC separation of metal ions using cerium (IV) antimonate as the solid phase are described. Using an acetonitrile- HNO₃ solvent Pb²⁺ can be separated quantitatively (2–10 μg) from several other ions. A quantitative spectrophotometric assay using p-nitroso-dimethylaniline is proposed.     

Interpretation of the Mechanisms of Chromatographic Separation on CN-Silica. Part I: TLC of Metal Complexes

JPC – Journal of Planar Chromatography – Modern TLC - The chromatographic behavior of four mixed tris(β-diketonato) complexes of the type [Co(acac)3-n(phacphac)n] (n = 0-3), three...     

Separation of Statin-Type Antihyperlipidemic Drugs by Reversed-Phase TLC

JPC – Journal of Planar Chromatography – Modern TLC -     

Separation of Aminoglycosides by Normal- and Reversed-Phase TLC

JPC – Journal of Planar Chromatography – Modern TLC - The normal-phase (NP) and reversed-phase (RP) thin-layer chromatographic separations of aminoglycosides (streptomycin, kanamycin,...     

阴离子交换分离－脉冲安培检测分析糖类化合物的进展

简述了糖的主要生物学作用及测定糖的主要方法，重点讨论了近年来建立起来的高效阴离子交换色谱－脉冲安培检测（ＨＰＡＥＣ－ＰＡＤ）技术。对此技术的基本理论、应用现状及优缺点进行了较为详细的叙述。     

Influence of Modifier-Free Hydroxide Eluents on the Separation of Carbohydrates by Anion Exchange Chromatography

Eluents based on low hydroxide concentrations are favourable in terms of selectivity for the separation of selected carbohydrates with anion exchange chromatography (AEC) and pulsed amperometric detection. The order of retention of many carbohydrates such as sucrose can be changed simply by selecting the appropriate hydroxide concentration.Instable retention times and weak detection efficiency were observed for hydroxide concentrations below 30mM without modifier. The time dependence of this retention loss was studied by step-changes of the eluent concentration. Linear behaviour with time is observed for all carbohydrates investigated. The slope of the relative decrease of retention is dependent on column capacity and presumably on its carbonate contents.The decrease in retention can be effectively suppressed by using a scavenger column filled with a high-capacity, strong anion exchanger. The variation of retention times were lowered from up to 100% to typically less than 1% during 72h of operation for a 10mM NaOH eluent without any modifier.     

The Use of Reverse-Phase Columns for Separation of Unsubstituted Carbohydrates

Reverse-phase chromatography can be used to separate unsubstituted oligosaccharides using water as the eluent. The retention time of the individual oligosaccharides was found to be dependent on the molecular weight of the oligosaccharide and the type and the anomeric configuration of the linkage. This technique can be used for characterizing polysaccharides based on identification of the oligosaccharide fractions obtained by partial acid hydrolysis or for the isolation and purification of oligosaccharides.     

Separation of Sulphonium Salts by Ion Chromatography: Five- and Six-Membered Cyclic Sulphonium Salts

Abstract

Several cyclic 5-and 6-membered sulphonium compounds were separated by ion pair chromatography on a opti-dbb ion pair column. The salts show specific retention behavior when using different mixtures of acetonitrile and aqueous sodium perchlorate solutions as eluents. The increase of retention times with extending chain length of the alkyl group R and with ring size is due to an increase of the solute molecular surface areas which were also calculated. The obtained retention parameters give additional information for structural determination.     

Improved Separation of Polyols and Carbohydrates by High Performance Liquid Chromatography

Abstract

A reliable High Performance Liquid Chromatographic analysis of glucose-fructose-sucrose-sorbitol and mannitol is developed. A Sugar Pak I column at 85°C is used employing water as the mobile phase. The separation is completed within 20 minutes, and the resolution is very acceptable.     

液相色谱法分离金属螯合物的进展

综述了用薄层液相色谱法和柱液相色谱法分离金属螯合物的进展及其在金属离子分析方面的应用。     

薄层色谱法分离菠菜色素及胡萝卜素含量测定

采用薄层色谱法分离菠菜叶片中的色素,并对其胡萝卜素的鉴别和含量测定.以硅胶G作为吸附剂,石油醚/乙醇/丙酮=3/2/1(体积比)的混合溶液为提取剂,石油醚/丙酮=2/1(体积比)的混合溶液为展开剂为最佳条件,提取和分离菠菜色素.菠菜中的胡萝卜素用薄层扫描仪在波长464.5nm条件下进行测定.结果表明,胡萝卜素在0.03～0.21μg范围内呈现良好的线性关系(r=0.999 8),加标回收率为95.25%～96.44%,相对标准偏差为0.59%.该方法的重复性、稳定性均满足分析的需要.     

Direct Phenylamination of 6-Aminonaphthacenequinones Promoted by Metal Salts

6-Amino-5,12- and -5,11-naphthacenequinones react with aniline in the presence of cobalt, copper, and manganese salts, resulting in replacement of hydrogen in the peri-position with respect to the carbonyl group by phenylamino group and formation of 11- and 12-phenylamino-6-amino(phenylamino)-5,12- and -5,11-naphthacenequinones.     

TLC Separation of Metal Ions Using Di(n-butyl)dithiophosphoric Acid and Neutral Organophosphorus Ligands

JPC – Journal of Planar Chromatography – Modern TLC - Thin-layer chromatographic separation of U(VI), Th(IV), the lanthanides Ln(III), (La(III), Ce(III), Pr(III), Sm(III), Gd(III),...     

The Effect of Secondary Chromatography on Quantitative TLC

Most of TLC analysis are performed in the UV and visible spectral region by measuring reflectance with a slit-scanning densitometer or a CCD camera (1-3). However, such measurements are restricted only to the surface of the TLC plate and do not take into account the vertical sub-surface concentration distribution governed by secondary chromatography (4-7) within the sorbent. It is therefore important to investigate effects connected with secondary chromatography in order to reveal their origin, and to. estimate their impact on the results of TLC measurements and their reproducibility.     

Separation of some antihistamines on impregnated TLC silica plates

Different metal salts have been tried as impregnating reagents for developing TLC separation schemes for some antihistamines on silica gel 'G' plates, using a new solvent system benzene + dimethyl formamide + acetic acid (30:10:7). Spots were visualized by spraying with a solution of Dragendroff's reagent.     

烷基磷酸酯盐分离技术的研究及波谱表征

通过对常压硅胶柱色谱分离条件的研究,实现了对工业合成烷基磷酸酯盐的分离。对两种分离产物进行IR、^1H-NMR、^31P-NMR和原子发射光谱分析,确定出其结构,验证了用常压硅胶柱色谱分离烷基磷酸单酯和双酯盐的可行性,并对硅胶柱色谱分离烷基磷酸酯盐进行了初步探讨。     

金属盐添加剂对甲醇羰基化反应的助催化研究

以[Rh(CO)2Cl]2为催化剂,以Sn、Pb、Cr、Zr金属盐作为添加剂,在催化甲醇羰基化制乙酸的反应中系统考察了不同添加剂对反应的影响.试验证明,含有添加剂的反应体系具有更高的催化活性和选择性,其中乙酸的时空收率最高达到40mol/(L·h)以上.