Gold nanoparticles are tiny particles of gold that range in size from 1 to 100 nanometers. Due to their small size, they exhibit unique optical, electronic, and chemical properties that differ from bulk gold. These properties make them useful in various applications, including medical imaging, drug delivery, and as catalysts in chemical reactions. In the field of nanotechnology, gold nanoparticles can be easily modified to attach to specific molecules, allowing for targeted therapies in cancer treatment. Their biocompatibility and stability also make them suitable for use in biosensors and diagnostic tools, enhancing the detection of diseases at early stages.