While colloidal gold is highly effective, alternative labeling methods include: 1. Fluorescent Dyes: These are commonly used in immunofluorescence to label and visualize proteins. 2. Enzyme Conjugates: Enzymes like horseradish peroxidase (HRP) are used in immunohistochemistry to catalyze colorimetric reactions. 3. Quantum Dots: These are semiconductor nanoparticles that offer high brightness and stability for imaging applications.
