Precipitation
Precipitation — The formation of an insoluble solid from a solution, often caused by pH changes, high concentration, or mixing incompatible solvents during peptide handling.
What Is Precipitation?
Precipitation is the formation of an insoluble solid from a solution, used in peptide research for crude purification, concentration, and removal of contaminants. Peptide precipitation can be intentional (purification step) or unintentional (aggregation during storage or formulation).
Precipitation Methods
- TCA/acetone: 10-20% TCA or cold acetone precipitates peptides from complex mixtures for proteomic sample prep
- Ammonium sulfate: Salting-out precipitation at defined saturation percentages
- pH adjustment: Precipitation at pI where peptide has zero net charge and minimum solubility
- Anti-solvent: Diethyl ether or MTBE addition to precipitate peptides from organic solutions
Frequently Asked Questions
What is Precipitation?
The formation of an insoluble solid from a solution, often caused by pH changes, high concentration, or mixing incompatible solvents during peptide handling.
Why is Precipitation important in peptide research?
Precipitation is a fundamental concept in chemistry as it relates to peptide science. It directly influences experimental design, compound characterization, and the reliability of research outcomes across biochemistry and molecular biology disciplines.