Protein Precipitation (Salting Out): Concentrates and fractionates proteins using ammonium sulfate cuts from complex mixtures.

Antibody Enrichment: Precipitates immunoglobulins from serum or ascites as a primary purification step.

Hydrophobic Interaction Chromatography (HIC): Provides high-salt conditions to promote binding and enables stepwise reduction for elution.

Protein Crystallization: Serves as a precipitant component in crystallization screens to drive nucleation and crystal growth.

Sample Clarification: Selectively precipitates contaminants to clarify cell lysates and conditioned media.

Biomolecule Concentration: Concentrates proteins and macromolecular complexes by selective salting out prior to downstream analysis.

Phase Separation with PEG: Facilitates aqueous two-phase separations (PEG–salt systems) for partitioning of target proteins.

Solubility and Stability Studies: Modulates ionic strength to map protein solubility curves and assess aggregation thresholds.

Buffer Formulation: Used to prepare high-salt buffers that modulate protein–protein and protein–ligand interactions during purification.