Positively and negatively charged Nanogold® labels may be used as ionic labels, to stain biological structures with opposite charges.
- Negatively charged Nanogold® labels have multiple carboxyl groups, and will stain features containing many positively ionizing groups.
- Positively charged Nanogold® labels have multiple amines on its surface and may therefore stain negatively charged features.
12 nm Nanogold® Labeling Reagents
Precise, permanent Nanogold® labeling reagents – Now in a larger size!
12 nm Nanogold® brings the power and versatility of Nanogold® in a even larger and more readily visualized 12 nm size. Like our smaller 5 nm and 1.4 nm Nanogold® reagents, it covalently reacts at specific sites under mild buffer conditions to give a well-defined product that may be purified chromatographically or by ammonium sulfate precipitation.
Unlike conventional colloidal gold, 12 nm Nanogold® does not require any additional macromolecules for stabilization. Conjugate probes are often smaller than colloidal gold probes and can achieve higher resolution because they can be prepares using smaller targeting agents, giving more precise and more nearly quantitative labeling.
Make any molecule a gold probe!
Unconjugated 12 nm Nanogold®, showing monodisperse, highly regular, spherically symmetrical 12 nm gold core and uniform, consistent ligand coating. This ensures a highly regular particle size and reliable, reproducible labeling and EM results.
Nanogold® brings the versatility of fluorescent conjugation to gold labeling.
Now you have a choice of sizes for Nanogold®: 1.4, 5 or 12 nm, enabling multiple labeling for electron microscopy without silver or gold enhancement!
- Antibodies
- Proteins
- Peptides
- Oligonucleotides and nucleosides: DNA, RNA and PNA
- Nanostructured materials
- Hormones
- Polymers
- Surfaces
Features and Advantages
- Stable, soluble and biocompatible. Designer coating gives solubility and biocompatibility so conjugates and probes may be used in vivo.
- Low background. No residual charge: minimal non-specific binding.
- Highly monodisperse. Size variation less than 10% for 12 nm. 1.4, 5 and 12 nm Nanogold enable double or even triple labeling with non-overlapping sizes
- Molecular precision. Use smaller targeting agents to make smaller primary probes that get the gold closer to the target.
- Site-specific conjugation enables programmed incorporation into nanostructured materials or components of self-assembling systems.
- No need for additional proteins or polymers: preparation is straightforward with no need for salt titration.
- Pick the optimum size: smaller for high resolution, molecular labeling, larger for visualization on a cellular scale.
- Easily enhanced. Enlarge with silver or gold enhancement and retain higher monodispersity – or achieve super-sensitive detection for blots and optical detection systems. If larger particle sizes are needed, 12 nm Nanogold® may easily be enhanced with:
Depending on the reagents used, a brief exposure (1 – 4 minutes) produces highly visible grains 20-30 nm in size for wide-field electron microscope visualization, while longer development times produce black signals, readily differentiated from organic chromogens, that are easily seen in the light microscope and on immunoblots, gels and Western blots.