By combining gold and fluorescence into one immunoprobe, the same specimen may be imaged using both fluorescence microscopy (e.g., with a confocal microscope) and at the ultrastructural level by electron microscopy.

FluoroNanogold™is now available with Alexa Fluor®* 647, 546, 488 or 594, giving you the benefits of brighter fluorescence, reduced photobleaching, and compatibility with a wider pH range, or in its original formulation with fluorescein as the fluorophore.

Unlike colloidal golds which quench fluorescence, tiny Nanogold® lets the fluorescence shine through. All components are covalently attached to ensure stability and long shelf life. Fab’ antibody fragments are much smaller probes than IgG conjugates, and have shown excellent penetration into cells and nuclei. FluoroNanogold™conjugates are chromatographically purified to eliminate any aggregates, free gold or unattached fluorescent molecules.

• Unprecedented correlation between fluorescence and EM data.
• Single labeling procedure means less chance for specimen perturbation.
• Choice of new fluorophores for brighter fluorescence, lower background and multicolor labeling.
• Same excellent penetration as found with Nanogold®: much better than 5 and 10 nm colloidal gold probes.
• FluoroNanogold™ probes are smaller than IgG conjugates (we use Fab’ fragments).
• Covalent coupling of both labels gives stability and long shelf life.
• Conjugates are stable and fluorescent at a wide range of pH and ionic strengths.

Applications

• Correlative fluorescence and electron microscopy 
• Check your labeling by fluorescence before processing for EM
• Monitor a dynamic process by fluorescence to determine when to fix and process for EM.
• Differentiate different targets using different fluorophores.