Colloidal gold refers to a colloidal system formed by suspending nanoscale gold particles in an appropriate solution. The size of gold particles typically ranges from 1 to 100 nanometers. Colloidal gold has attracted much attention due to its unique optical properties and chemical stability.
Colloidal gold has several important uses:
1. Biosensing: Due to the surface plasmon resonance (SPR) effect of gold particles, they exhibit significant absorption and scattering characteristics in the visible light range. This has led to the widespread application of colloidal gold in the field of biosensors, such as for detecting the presence and concentration of biological molecules such as proteins and DNA.
2. Medical diagnosis: Colloidal gold has a wide range of applications in medical diagnosis due to its ability to control its optical properties by adjusting its particle size and surface modification. Colloidal gold can be used for laser scanning confocal microscopy (LSCM), surface enhanced Raman spectroscopy (SERS), and biomarker detection.
3. Optical materials: Colloidal gold has significant optical properties and is widely used in the field of optical materials. They are used to prepare optical filters, optical lenses, photovoltaic devices, etc.
4. Catalyst: Nanoscale colloidal gold particles have high surface area and high activity, which makes them have potential in the field of catalysis. Colloidal gold can be used as a catalyst for various chemical reactions, such as oxidation reactions, reduction reactions, and as a carrier for catalysts.
5. Materials Science: Colloidal gold can also be applied in materials science research, such as preparing nano gold structured materials, preparing nanowires, nanogrids, etc.
In summary, colloidal gold has broad application potential in fields such as biosensing, medical diagnosis, optical materials, catalysts, and materials science due to its unique optical properties and chemical stability.
