By in General FAQs

Affinity of Protein A, Protein G and Protein A/G

Protein A, Protein G and Protein A/G are often used in antibody purification and other applications such as immunoprecipitation (IP) and chromatin immunoprecipitation(ChIP). Their binding abilities to antibodies of different subtypes and species are varied. How to choose correct types of protein to purify your sample? Here, we list the antibody binding properties of Protein A, Protein G and Protein A/G.

Note: +++ strong binding; ++ medium binding; + weak binding; - no binding

Species Antibody subtype Protein A Protein G Protein A/G
Human Total IgG +++ +++ +++
IgG1 +++ +++ +++
IgG2 +++ +++ +++
IgG3 + +++ +++
IgG4 +++ +++ +++
IgM + - +
IgD - - -
IgA + - +
Mouse Total IgG +++ +++ +++
IgG2a +++ +++ +++
IgG2b ++ ++ ++
IgG3 + ++ ++
IgM - - -
Rat Total IgG + ++ ++
 IgG1 + ++ ++
 IgG2a - +++ +++
 IgG2b - + +
 IgG2c +++ +++ +++
Rabbit Total IgG +++ +++ +++
Goat Total IgG + +++ +++
Sheep Total IgG + +++ +++
Guinea pig Total IgG +++ + +++
Hamster Total IgG ++ ++ ++
Donkey Total IgG ++ +++ +++
Horse Total IgG + +++ +++
Cow Total IgG + +++ +++
Pig Total IgG +++ + +++
Dog Total IgG +++ + +++
Cat Total IgG +++ + +++
Chicken Total IgY - - -