Technical information > IgG

Quick facts about IgG

IgG is the main low molecular weight immunoglobulin present in mammalian serum, and makes up 75% of serum immunoglobulins.

  • Molecular mass: ~150 to 170 kDa depending on the species. IgG consists of two light chains and two heavy chains connected by disulfide bonds. The light chains have a molecular weight of around 23 kDa each, while the heavy chains are around 50 kDa each for H chain subclass ϒ1,2,4, and 60 kDa for ϒ3.
  • Isoelectric point: 6.1-8.5 (7.3 ± 1.2) if monoclonal (polyclonal antibodies do not have a set isoelectric point as they are a pool of various classes).
  • Concentration in serum: 10-20 mg/ml
  • Glycosylation (by weight): 3%
  • Extinction coefficient at 280 nm: 1.36 for a solution of 1 mg/ml, Johnstone, A. and Thorpe, R. (1988) “Immunoassays”. In: Johnstone, A. and Thorpe, R., Eds., Immunochemistry in Practice, 2th Edition, Blackwell Scientific Pub, London, 257-260.
  • IgG molecule dimensions: 13.7 nm (width), 8.4 nm (height), Horng et al. 2008
  • Distribution in the body: intra- and extravascular
  • Immunological function: secondary response
  • Structure: self-assembles into hexamers, which form two dimensional crystals in aqueous solution (Shinichiro et al. 2014, Nature Materials)
  • Function: Activate mammalian complements 
  • Binds to: Protein A or Protein G

Molecular weight to molar quantity conversion     MW and pI of various animal immunoglobulins     Main properties of human immunoglobulins     Protocol and description of IgG neutralization

Examples of techniques where IgG antibodies have been successfully used

Agrisera Secondary Antibodies bind to

Bovine IgG | Cat IgGDog IgG | Goat IgG  | Hamster IgG | Llama IgG | Rabbit IgG | Sheep IgG | Donkey IgG | Guinea pig IgG | Human IgAHuman IgE | Human IgG | Human IgM | Mouse immunoglobulins  | Rat IgG

Available immunoglobulins from various species in different purity grades

Purified Bovine IgG   Purified Chicken IgG   Purified Donkey IgG   Purified Goat IgG
Purified Mouse IgG   Purified Rabbit IgG   Purified Rat IgG   Other species

Further information

Agrisera Antibody Production Guide

Information on antibody storage


Recommended literature about IgG antibodies

  • Using Antibodies: A Laboratory Manual, E. Harlow and D. Lane, 1999,
    ISBN: 0879695447; Publisher: Cold Spring Harbor Laboratory Press.
  • Immunochemistry in Practice, A. Johnstone and R. Thorpe, 1988,
    ISBN:0-632-01723-6; Publisher: Blackwell Scientific Publications.

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