Colloidal gold - Colloidal gold conjugation
Colloidal gold is a suspension of gold nanoparticles with intensely red color. It is used as a sensitive direct label for rapid diagnostic tests (test strips). For this application the gold particles must be conjugated to the specific protein component. Two different methods are established:
- direct conjugation of proteins to colloidal gold
- binding of biotinylated proteins to universal streptavidin gold
Streptavidin gold
MicroCoat's proprietary procedure provides gold conjugates with excellent stability and lot-to-lot reproducibility. This is achieved by using the modular streptavidin-biotin system:
- Colloidal gold is conjugated to streptavidin. This conjugate is very stable and can easily combined with any specific component.
- The specific component (e.g. antibody) is mono-biotinylated according to an established procedure in order to avoid aggregation.
- Combination of streptavidin gold with the mono-biotinylated protein yields stable gold conjugates.
As this approach relies on two highly reproducible production procedures, it provides conjugates with minimal lot-to-lot variation.
Streptavidin gold is available from stock
- Streptavidin gold Specification sheet (Article-No. 605044)
For more information, please contact MicroCoat by phone, email or fax.
