It is represented by Greek letter α (alpha) and is also known as alpha level.

TLS Online TPP Program

#Id: 2780

#Unit 13. Methods in Biology

The basis of all forms of chromatography is the distribution or partition coefficient (Kd), which describes the way in which a compound (the analyte) distributes between two immiscible phases.

TLS Online TPP Program

#Id: 2781

#Unit 13. Methods in Biology

A chromatogram is a pictorial record of the detector response as a function of elution volume or retention time, It consists of a series of peaks or bands.

TLS Online TPP Program

#Id: 2782

#Unit 13. Methods in Biology

The retention time tR for each analyte has two components

 i - dead time, tM. &

ii - adjusted retention time, t’R.

TLS Online TPP Program

#Id: 2783

#Unit 13. Methods in Biology

t’R is characteristic of the analyte and is the difference between the observed retention time and the dead time:

TLS Online TPP Program

#Id: 2784

#Unit 13. Methods in Biology

Retention factor (k) is simply the additional time that the analyte takes to elute from the column relative to an unretained or excluded analyte that does not interact with the stationary phase and which, by definition, has a k value of 0. Thus

TLS Online TPP Program

#Id: 2785

#Unit 13. Methods in Biology

The ratio VS/VM is referred to as the volumetric phase ratio, b. Hence: