1) c) separation techniques

Centrifuge separates substances of different densities. More dense components settle in the pellet; less dense components remain in the supernatant.

Paper and thin layer chromatography can be used for separating different substances such as amino acids and sugars

Differing solubility in the solvent used The speed that each solute travels along the chromatogram depends on its differing solubility in the solvent used.

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.

Charged macromolecules move through an electric field applied to a gel matrix. SEPERATES BASED OF CHARGE!

Separates proteins by size alone. SDS–PAGE gives all the molecules an equally negative charge and denatures them, separating proteins by size alone. this means that the proteins can be separated based on their size as they migrate towards the positive electrode. Small proteins travel further through the gel than large proteins.

Iso-electric Point

IEP is the pH at which a soluble protein has no net charge and will precipitate out of solution.

If the solution is buffered to a specific pH, only the protein(s) that have an IEP of that pH will precipitate.

Proteins can be separated using their isoelectric points in electrophoresis

Soluble proteins can be separated using an electric field and a pH gradient. A protein stops migrating through the gel at its IEP in the pH gradient because it has no net charge.