Why ascending method of paper chromatography is preferred, Biology

Assignment Help:

Why Ascending Method of Paper Chromatography is Preferred?

The ascending method is preferred because of the simplicity of the set up. In actual method the substance to be separated is applied as a spot in a suitable solvent with the help of a capillary tube and hot blower. The paper is then suspended vertically inside a sealed chamber to make its lower end dip into a solvent. Due to capillary action, the solvent ascends along the filter paper that forms the mobile phase, while the water held immobile by the cellulose fibres of the paper forms the stationary phase.

After the solvent front has run almost to the upper end of the filter paper, the latter is removed from the chamber and dried. The paper is then suitably stained to locate separate functions as coloured spots. Sometimes, to enhance the resolution of the spots and to verify the authenticity of the material, the chromatogram is subjected to two dimensional paper chromatography. After it is run in single dimension in one solvent system, it is dried and rotated to 900 and rechromatographed using a second altogether different solvent system. Finally the filter paper is dried and stained. The spots are better resolved after chromatography in the second dimension. In descending paper chromatography, the filter paper is suspended vertically down from the solvent chamber at the top so that the liquid and the solutes migrate down the paper.


Related Discussions:- Why ascending method of paper chromatography is preferred

Microfilaments - cytoskeletal structures, MICROFILAMENTS Discovered ...

MICROFILAMENTS Discovered by Pelvitz. These are smallest cell structure. These are non-living structures. These are solid structures, consists of actin protein (c

Disease occurrence due to climate change in animals, Disease occurrence due...

Disease occurrence due to climate change The movement of animal diseases across physical and political boundaries threatens food security and creates a global public co

Principles of haccp, Principles of HACCP A) Determine the  Critical  Co...

Principles of HACCP A) Determine the  Critical  Control  Points  (CCPs) B) Establish  Critical Limit(s) C) Establish a  System  to  Monitor Control of the  CCP D) Esta

Explain the uses of hydrocolloids, Explain the uses of hydrocolloids In...

Explain the uses of hydrocolloids In particular, hydrocolloids can provide water for increasing the flexibility (plasticizing) of other food components. These can also affect i

Delimitation and limitation, Delimitation and Limitation: There may  b...

Delimitation and Limitation: There may  be many  aspects of the problem that need  to be  explored, but  it  is difficult to  cover all aspects in  a single research study bec

Aortic valve replacement with replacement of aortic root, Aortic Valve ...

Aortic Valve Replacement with Replacement of Aortic Root :  When there is aneurysm of ascending aorta with aortic regurgitation, aortic root replacement is done. This

Define the historical example of neuroscience, Normal 0 false ...

Normal 0 false false false EN-IN X-NONE X-NONE

How poor selection of food causing the underweight, How Poor Selection of F...

How Poor Selection of Food causing the Underweight? Poor Selection of Food: Poor selection of food along with irregular eating habits may be responsible for insufficient food

Determine the final cell volume, Find the initial osmotic pressure at room ...

Find the initial osmotic pressure at room temperature for a cell if the only ions present are KCl and NaCl on either side of the membrane. Assume the concentrations for K+ and Na+

Describe coronary spasm, Q. Describe Coronary Spasm? Usually spasm deve...

Q. Describe Coronary Spasm? Usually spasm develops at the site of subcritical or critical stenoses, but it may also occur in angiographically normal coronary arteries, the so c

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd