Chromatography solvent systems

Chromatography solvent system, hexane-diethyl ether-acetic acid (80 20 1) in a chromatography jar... 

B 2. Why is acetic acid added as a minor component (l°/o) of the chromatography solvent system ... 

Small funnel and qualitative grade filter paper Silica gel thin-layer plates (20 X 20 cm and 5 X 10 cm) Chromatography solvent system, hexane-diethyl ether-acetic acid (80 20 1) in a chromatography jar... 

The [...coloured solid/liquid] residue was purified by [flash chromatography (solvent system) or distillation, b.p. L°C at W mmHg or recrystallization, m.p. T°C], to provide the title compound as a [.coloured solidAiquid] M g, XX% yield, This says how the product was purified - choose the appropriate statement and insert the required information. 

Paper Chromatography.—Solvent systems have been developed for the separation of trichloromethyl- phenyl-, and pentafiuorophenyl-phosphonic and -phosphinic acids. Phosphoramidates and their hydrolysis products have been chromatographed, using triethylamine as a buffer. Silica gel on glass-fibre sheets may be used to separate inositol from its phosphate and to analyse phosphatide glyceryl ethers. ... 

Martin, M. Classification of countercurrent chromatography solvent systems on the basis of the capillary wave- 11. length. Anal. Chem. 1994, 66(1), 168. 

Solvent system does play very important role in the isolation and extraction of psilocybin. It is quite evident from the early phase of research activities that very polar solvent, such as methanol or mixtures of ethanol and water, is most suitable for the isolation of psilocybin. The polar properties of the phosphate group make psilocybin soluble in water and methanol (polar solvent), and as a result solubility decreases with the decrease in polarity, i.e., less soluble in polar solvent. In comparison, psilocin is less polar and thus readily soluble in polar solvent, such as 1-chlorobutane. For thin layer chromatography, solvent systems comprising of n-butanol + acetic acid + water (20 10 10) or methanol + con. ammonia solution (100 1.5) may be used to develop the plates, and visualization of the blue spots on fluorescent background can be made using ultraviolet (UV) light at 254 and 365 nm. The absorption characteristics of both... 

A(ii). Flash Silica Chromatography, solvent system CHCI3 / CH30H/conc.NH40H... 

Instmmental methods of analysis provide information about the specific composition and purity of the amines. QuaUtative information about the identity of the product (functional groups present) and quantitative analysis (amount of various components such as nitrile, amide, acid, and deterruination of unsaturation) can be obtained by infrared analysis. Gas chromatography (gc), with a Hquid phase of either Apiezon grease or Carbowax, and high performance Hquid chromatography (hplc), using siHca columns and solvent systems such as isooctane, methyl tert-huty ether, tetrahydrofuran, and methanol, are used for quantitative analysis of fatty amine mixtures. Nuclear magnetic resonance spectroscopy (nmr), both proton ( H) and carbon-13 ( C), which can be used for quaHtative and quantitative analysis, is an important method used to analyze fatty amines (8,81). 

Benzene, which has been used as a solvent successfully and extensively in the past for reactions and purification by chromatography and crystallisation is now considered a very dangerous substance so it hasto be used with extreme care. We emphasise that an alternative solvent system to benzene (e.g. toluene, toluene-petroleum ether, or a petroleum ether to name a few) should be used first. However, if no other solvent system can be found then all operations involving benzene have to be performed in an efficient fumehood and precautions must be taken to avoid inhalation and contact with skin and eyes. Whenever benzene is mentioned in the text an asterisk e.g. C Hg or benzene, is inserted to remind the user that special precaution should be adopted. 

Geraniol [106-24-1] M 154.3, b 230 , d 0.879, n 1.4766. Purified by ascending chromatography or by thin layer chromatography on plates of kieselguhr G with acetone/water/liquid paraffin (130 70 1) as solvent system. Hexane/ethyl acetate (1 4) is also suitable. Also purified by GLC on a silicone-treated column of Carbowax 20M (10%) on Chromosorb W (60-80 mesh). [Porter Pure Appl Chem 20 499 7969.] Stored in full, tightly sealed containers in the cool, protected from light. 

These workers used binary solvent systems over a range of mole fractions to determine, for each solute, the constants a and b of equation (8.2). For methyl and phenacyl esters, TLC was used, while overpressured layer chromatography (OPLC) was used for dansyl amino acids. Nurok and co-workers (11) also evaluated how the quality of a simulated separation varies with changing solvent strength by using the inverse distance function (IDF) or planar response function (PRF), as follows ... 

Countercurrent chromatography (CCC) refers to a chromatographic technique which allows the separation of solutes in a two-phase solvent system subjected to a gravitational field. Two immiscible liquid phases, constituted by one or more solvents or solutions, are submitted to successive equilibria, where the solutes to be separated... 

Purification of the activation products (PMs). The methylamine activation product dissolved in methanol is purified by chromatography, first on a column of silica gel using a mixed solvent of chloroform/ethanol, followed by reversed-phase HPLC on a column of divinylbenzene resin (such as Jordi Reversed-Phase and Hamilton PRP-1) using various solvent systems suitable for the target substance (for example, acetonitrile/water containing 0.15% acetic acid). 

Thin layer chromatography of (-)-DAG on Silica Gel G using the solvent system, benzene methanol acetone acetic acid (70 20 5 5), shows one spot with Rf 0.7. 

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