P6855 Sigma

Protein A–Gold

~2.5 A520 units/mL, aqueous glycerol suspension, 17-23 nm (monodisperse), 20 nm nominal (colloidal gold)



Related Categories Antibodies, Protein A, G and L Detection Reagents, Secondary Antibodies More...
form   aqueous glycerol suspension
concentration   ~2.5 A520 units/mL
particle size   17-23 nm (monodisperse)
nominal   20 nm (colloidal gold)
conjugate   gold conjugate
storage temp.   2-8°C


Other Notes

Protein A, extracellular (P 6031), adsorbed to colloidal gold.

Physical form

Suspension in 0.01 M phosphate buffered saline, pH 7.4, containing 1% bovine serum albumin, 20% glycerol, and 15 mM sodium azide.


Protein A-Gold can be used in dot blot. It can also be used to detect immunoglobulins.

General description

Protein A is a 42 kD, highly stable cell surface receptor isolated from Staphylococcus aureus which binds selectively and with high affinity to the Fc portion of IgG from various species.Protein A-gold is an electron dense, non-fading marker and can be used as a probe in electron microscopy (TEM and SEM), light microscopy and blotting. Protein A - 20 nm colloidal gold reacts specifically with IgG of human.

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Safety Information

NONH for all modes of transport
WGK Germany 


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