Module 3d: Chromatography Flashcards
Refers to the group of techniques used to separate complex mixtures on the basis of different physical and chemical interactions between the compounds and the stationary phase.
Chromatography
Four basic components in any chromatographic technique:
- stationary phase
- mobile phase
- column
- eluate
Component that carries the complex mixture (sample)
mobile phase
component which can either be solid or liquid through which the mobile phase flows
stationary phase
component that holds the stationary phase
column
The separated components
eluent
5 separation mechanisms of chromatography
- ion-exchange
- partition
- adsorption
- size exclusion
- affinity mechanisms
Separation mechanism that is based on the differences or magnitude of their ionic charge.
ion-exchange chromatography
An exchangable ion found in close proximity with the fixed charge to maintain electrochemical neutrality.
counterion
Ion exchange chromatography used primarily for strongly acidic groups
Cation-exchange particles
acids have high H+ that can exchange with negatively charged stationary phase
Ion exchange chromatography used primarily for strongly basic quarternary amines with positive charges.
anion exchange packings
basic solutions have less H+ and adhere to negatively charged stationary phase
Chromatography involving separation of solutes based on their differential distribution of between two immiscible liquids
partition chromatography
partition chromatography separates solutes based on
the difference in solubility of the solute molecules between the stationary and mobile phase
Partition chromatography is classified into
gas liquid chromatography
liquid liquid chromatography
Liquid liquid chromatography is further classified into:
normal phase
reverse phase
Normal phase LLC has
stationary - polar
mobile - non- polar
Reverse phase LLC has
stationary - non polar
mobile - polar
Version of partition chromatography wherein analytes elute in order of increasing polarity
hydrophilic interaction chromatography
Separation technique based on the differences between the adsorption and desorption of solutes at the surface of a solid.
Adsorptiom chromatography
adsorption chromatography is also known as
liquid- solid chromatography
In adsorption chromatography, the molecules that are most soluble in the mobile phase move the ___________
fastest
Separation method based on the molecular sizes and shape
Size exclusion/ steric exclusion chromatography
In size exclusion chromatography, the molecules that remain entirely in the mobile phase are large or small??
large
Process where hydrophilic gel isused in separation of enzymes, antibodies and proteins.
Gel filtration
example of hydrophilic gels
dextran
agarose
Process where hydrophobic gel is used to separate triglycerides and fatty acids
Gel permeation