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Different terms and comparison of TLC and paper chromatographic techniques?


Different terms and comparison of TLC and paper chromatographic techniques?
Rf  Value:
 Paper and thin-layer chromatographic techniques includes those apparatus of a mixture which are  symbolize according to their relative mobility Rf  value
Equation of mobility factor:

 Rf = Distance travelled by component /Distance carried out by solvent .
  Dismally Rf values remains not constant for any given solute,sorbent,solvent
Chromatographic factors:

Chromatographic factors are given as follows:
 Quality of the stationary phase
Layer thickness humidity
Development distance and temperature.
Thin-Layer Chromatography:
Thin-layer chromatography TLC was first discovered in 1938


      
Replacement of Thin-layer chromatography:
Thin-layer chromatography has chiefly replace the paper chromatography due to following reasons
It is faster, more sensitive and more reproducible.
Resolution in thin-layer chromatography:
 Resolution speed in Thin-layer chromatography is  at a larger speed  as compared to paper chromatography due to the particles which are present on the plate are smaller in size and more sequencly arranged as compared to the fibers of the paper.

Experimental conditions for separation in column chromatography:
                                                                 
Conditions for an  experiment may  be change easily to obtain partition and can be used for column chromatography.
 Though thin-layer and column chromatography  cannot be interchanged due to following differences
e.g binders which are used in the thin-layer chromatographic plates vapor-phaseaatmospher of equilibrium in the tan of TLC and so on.




Advantages in Thin-layer chromatography:
TLC technique has following  advantages such as amount of  sample in high amount, put in low cost, Possible analysis of many samples and standards at the same time, preparation of sample in minimum amount and  plate which can be store for later identification and quantification.
Implement of TLC in different fields:

TLC can be used in different fields which includes environmental, clinical, forensic, pharmaceutical, food, flavors, and cosmetics.
Implement of TLC in food industry:

In food industry TLC can  be used for control of quality.
Example:
For example, corn and peanuts  which are to be examined  for aflatoxins or mycotoxins following to their processing into corn meal and peanut butter.
Implement of TLC in different  analysis fields:

Common process of thin-layer chromatography uses a thin ca. 250 µm thick layer of sorbent may be  stationary phase which is bound within a non-reactive support in a planar configuration. The support which is made on a glass plate commonly the size may be 20 cm × 20 cm but sheets of plastic and aluminum foil also are used.
Precoated plates:
Precoated plates are also available having different layer thicknesses, are available on commercial scale with a great variety of sorbents  which includes chemically modified silicas.
TLC sorbents:
Four frequently used TLC sorbents are silica gel
alumina
diatomaceous earth  
cellulose.
Modified silicas for TLC which contains polar may be non polar groups, so both normal and reversed-phase  separation process can  be carried out.

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