Gold nanoparticles are widely used in medical diagnostics due to their unique optical properties. They are employed in biosensors to detect diseases at an early stage, as they can bind to specific biomolecules and produce a visible color change. In cancer treatment, these nanoparticles are utilized for targeted drug delivery, ensuring that therapeutic agents are released directly into tumor cells while minimizing damage to healthy tissues. Additionally, gold nanoparticles are applied in photothermal therapy, where they absorb light and convert it into heat to destroy cancer cells. In the field of electronics, they are used to enhance the performance of conductive inks and coatings, improving the efficiency of electronic devices. Their antimicrobial properties also make them valuable in developing coatings for medical equipment to prevent infections. Furthermore, gold nanoparticles play a role in environmental science, aiding in the detection and removal of pollutants from water sources.