Ammonium Sulfate Precipitation

Ammonium Sulfate Precipitated IgG from Antisera

Immunoglobulin G (IgG) fractions are prepared from serum or antisera using classical ammonium sulfate precipitation techniques designed to enrich total IgG while preserving antibody activity. This method provides a cost-effective and reliable approach for producing concentrated polyclonal antibody preparations suitable for research, assay development, diagnostics, or further purification processes.

Overview

Ammonium sulfate precipitation is a widely used protein fractionation method based on controlled salt-induced precipitation (“salting out”). Under optimized conditions, IgG selectively precipitates from serum while many unwanted serum proteins remain in solution.

The resulting material consists of enriched total IgG isolated from the source antisera.

Typical Source Materials

IgG may be isolated from a variety of antisera sources including:

  • Rabbit antisera
  • Goat antisera
  • Sheep antisera
  • Horse antisera
  • Mouse antisera
  • Other mammalian serum sources

General Process

The purification workflow typically includes:

  1. Collection of serum or antisera
  2. Controlled ammonium sulfate addition
  3. IgG precipitation and recovery
  4. Centrifugation and pellet collection
  5. Reconstitution in appropriate buffer
  6. Desalting or dialysis to remove residual ammonium sulfate
  7. Filtration and formulation

Process conditions may be adjusted depending on serum source and downstream application requirements.

Product Characteristics

Typical ammonium sulfate–precipitated IgG preparations may offer:

  • Enriched total IgG fraction
  • Retained antibody binding activity
  • Reduced albumin and non-Ig serum proteins
  • Suitable starting material for additional purification
  • Compatible with labeling and conjugation procedures

Applications

These IgG fractions are commonly used in:

  • ELISA development
  • Immunoassays
  • Western blotting
  • Immunohistochemistry
  • Radioimmunoassays
  • Conjugate preparation
  • Antibody labeling
  • Research and diagnostic assay development

Advantages of Ammonium Sulfate Fractionation

  • Economical purification approach
  • Scalable for large-volume processing
  • Gentle on antibody activity
  • Reliable and well-established methodology
  • Suitable for polyclonal antibody enrichment

Available Options

Preparations may be supplied as:

  • Liquid formulations
  • Concentrated IgG solutions
  • Dialyzed preparations
  • Preservative-containing formulations
  • Custom buffer systems
  • Custom species or antisera sources

Quality Considerations

Each preparation may be evaluated for:

  • Protein concentration
  • Clarity and appearance
  • Buffer composition
  • Functional immunoreactivity
  • Optional purity assessment