Biomedical and agricultural applications of gold nanoparticles (AuNPs): a comprehensive review

The evolution of engineered nanoparticles (NPs); particularly metallic NPs have played an indispensable role in the development of nanotechnology. Among these NPs, gold nanoparticles (AuNPs) have attracted significant attention and are highly being utilized in several fields due to their exceptional properties. Gold nanoparticles were an emerging subject of intensive research due to their spherical shape, large specific surface area, and quick modification by functional groups. As the demand for AuNPs continuously increases; therefore, there is a pressing need to optimize the scientific approach to fully comprehend and exploit their potential. The effect of AuNPs on plant growth and development can either be beneficial or harmful, depending on the plant species and the concentration of NPs. Moderate concentrations of AuNPs have been found to induce primary and lateral roots, reduce oxidative stress, and elongate rosette diameter, while a higher concentration showed negative effects on plant growth and development. Gold nanoparticles also exhibit potent antibacterial, antiviral, and anticancer properties, making them most beneficial in various sectors, especially in the biomedical field. AuNPs are extensively being utilized across various sectors, but their application in the biomedical field is noteworthy, particularly in bioimaging, biosensing, targeted gene and drug delivery, theranostics, regenerative medicine, and tissue engineering. This review emphasizes the potential applications of AuNPs in diverse sectors including agriculture and biomedical, highlighting their potential impact (positive and negative) on plant growth. Furthermore, the review also aims to signify the mechanism of action of AuNPs and their efficacy against bacteria, viruses, and cancer cells.