Pharmaceutical Analysis

It is measurable concept,quantitavely determined by the ratio of useful output to total input.or it is defined as the ability to produce something with a  minimum amount of effort.

Eluate: It is the liquid substance used to remove ( the adsorbed substance) by washing with a solvent, mostly in chromatography.

The portion of the sample contained in the mobile phase.

Elution is the process of extracting one material from another by washing with a solvent ; as in washing of loaded ion-exchange resins to remove captured ions

This technique most widely used in this technique small quantity of the sample solution is introduced at the top of column. Pure solvent is then poured down the column this gives rise to differential migration of solutes In mobile phase.Each solute emerges from the Column exit depending on its partition coefficient.If the partition coefficient for the solutes in the sample are sufficiently different the mixture separates out into bands which migrate at different rates for s.p than sample components represents small fraction of column capacity 

Extractions are a way to separate a desired substance when it is mixed with others. The mixture is brought into contact with a solvent in which the substance of interest is soluble, but the other substances present are insoluble.