RP12 - separation of species via thin layer chromatography Flashcards
Define stationary phase
A solid or liquid in chromatography held by a solid support
Define mobile phase
A liquid or gas that moves through the stationary phase
What is the stationary phase made up of?
Aluminium oxide or silicon oxide
What is the use of thin layer chromatography?
Separate a mixture into its constituent parts for analysis
Describe the process of TLC
Add solvent to a jar and seal
Draw pencil line 1cm from bottom of TLC plate
Spot samples along pencil line using capillary tube
Add TLC plate to jar, ensuring solvent is below pencil line
Solvent rises up plate, bringing sample components up
Draw line where solvent finishes
Allow plate to dry
If spots are colourless, use UV
Why cant ink be used on TLC plate
Will dissolve in solvent and contaminate TLC
What determines the Rf value of a spot
Solubility in mobile phase and retention by stationary phase
Why do different amino acids have different Rf values?
They have different polarities that affect the retention in the stationary phase or solubility in the mobile phase
