Paper chromatography capillary action

Paper chromatography or more of 12 autonomic symptoms (e.g. shortness of breath, dizziness, palpitations, sweating). Separation of a mixture of compounds on filter paper according to their relative solubility in organic solvents that diffuse through the paper by capillary action. 

When analysts speak of paper chromatography, they mean that a piece of moist paper is used as the inert and stationary phases, the sample is placed as a small diameter spot at one end, and the components are eluted by having the mobile phase pass through the paper by capillary action. 

Paper chromatography is the simplest of the chromatographic techniques, and is often used to separate dyes in a mixture. In this technique the stationary phase is made up of water molecules that are trapped in the cellulose fibres of paper. The mobile phase is the aqueous or organic solvent that moves up the paper by capillary action. This capillary action is caused by the forces between the cellulose fibres of the paper and the solvent. Dyes that are more soluble in the solvent than they are in the water molecules of the stationary phase move rapidly up the paper, while those that are more soluble in the water are not carried as far up the paper (Figure 21.17). 

The main origin of multidimensional chromatography lies in planar chromatography. The development of paper chromatography, i.e. the partition between a liquid moving by capillary action across a strip of paper impregnated with a second liquid... 

The procedure of paper and thin-layer chromatography. A Application of the sample. B Setting plate in solvent chamber. C Movement of solvent by capillary action. D Detection of separated components and calculation of Rf. 

In paper chromatography and thin layer chromatography (TLC), the sample rises up by capillary action through a solid phase. 

Additional variations entail using columns of different sizes, made of different materials, and operated at different pressures and temperatures. For narrow-bore columns the walls can be coated with a sorbent layer and the packing removed (open tubular or capillary chromatography). Alternately one can do away with the column entirely, using an open granular bed (thin-layer chromatography, TLC) or a simple sheet of paper (paper chromatography, PC) into which liquids flow by capillary action (Section 4.7). 

Series of chromatograms showing the separation of black ink. Chromatography is an analytical process, which separates a compound into its constituent chemicals. Chromatography paper is dipped vertically in a solvent with the ink painted on it (left). Capillary action draws the solvent up through the paper (center) and dissolves the ink. As the solvent travels up the paper, it takes the various chemicals in the ink with it, separating them into a series of colored bands. (Courtesy of Andrew Lambert Photography/ Science Photo Library)... 

Carefully place the strip of chromatography paper into the beaker and allow the solvent to migrate by capillary action. It is important that the beaker remain undisturbed during this process. 

Paper chromatography (PC), a form of partition chromatography using paper as the stationary phase and capillary action as the driving force. 

Thin layer chromatography requires no pressure but instead relies on the capillary action of a solvent through a paper-like sheet of sorbent. Each constituent travels a different distance and the constituents are thus separated. Analysis is done manually, typically using various coloring or fluorescing reagents. 

Planar chromatography type of chromatography where the stationary phase is a flat film in the form of a thin layer of material coated onto a rectangular glass or inert plastic support plate (TLC) or as a paper sheet (PC). The mobile phase moves through the stationary phase by capillary action. 

In paper or thin-layer chromatography, the absorbent paper or layer of finely divided silica acts as both a support and a stationary phase, also trapping stationary solvent as the bulk solvent passes through by capillary action. In gas chromatography (GC) the stationary phase is usually a thin layer of oil on the inner surface of a long capillary tube, through which is pumped an inert carrier gas (the mobile phase) carrying the volatile sample molecules. 

Chromatography techniques include many specific technologies, but all involve passing the mixture through a stationary phase. The various components in the mixture will have different degrees of affinity for this stationary phase and will thus be separated. This affinity may be based upon charge, relative solubility, or adsorption. The major types of chromatography are capillary-action (paper and thin layer), column, gas-liquid, and counter-current. 

If the mobile phase is a gas or a supercritical fluid, it is necessary to let it flow through a tube, a so-called column, that contains the stationary phase. In the case of liquid chromatography one can choose between a column or planar geometry because the mobile phase can move through a sheet of paper or a thin layer by capillary action. If a column is used, the mobile phase is forced through it by pressure generated by a pump or by a gas stored in a pressurized cylinder. (As a preparative laboratory technique, liquid chromatography is also performed in columns packed with coarse stationary phases in this case simple hydrostatic pressme may be sufficient.)... 

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