Separation Techniques Flashcards
What is a centrifuge used for?
To separate substances with differing density
In a centrifuge where do the more dense components lie?
They settle in the form of a pellet
In a centrifuge where do the less dense components lie?
They remain in the supernatant
What are the different types of chromatography?
-paper chromatography
-thin layer chromatography
-affinity chromatography
What can paper chromatography and thin layer chromatography be used for?
To separate different substances such as amino acids and sugars
What does the speed that each solute travel along the chromatography depend on?
The differing solubility in the solvent used
What is affinity chromatography used to separate?
Proteins
What is the principal of affinity chromatography?
A solid matrix or gel column is created with specific molecules bound to the matrix or gel. Soluble target proteins in a mixture with a high affinity for these molecules become attached to them as the mixture passes down the column. Other non-target molecules with a weaker affinity are washed out
What is gel electrophoresis used to separate?
Proteins and nucleic acids
What is the principal of gel electrophoresis?
Charged macromolecules move through an electric field applied to a gel matrix
What are the two types of gel electrophoresis?
Native gels and SDS-PAGE
What do native gels separate proteins by?
Shape size and charge because the native gels don’t denature the molecules.
What can SDS-PAGE separate?
Proteins by size alone, because the SDS-PAGE gives all the molecules an equally negative charge and denatures them
Apart from the use of a centrifuge, chromatography or gel electrophoresis how else can proteins in a mixture be separated?
By use of their isoelectric points
What is an isoelectric point?
The pH at which a soluble protein has no net charge and will precipitate out of a solution.
