Catalytic Transformations in Cells using NHC@AuNPs

Gold nanoparticles (AuNPs) are one of the most well-investigated metal nanoparticles (MNPs) showing a wide range of applications in numerous areas, including catalysis and biomedicine. This is due to their unique optical properites, high surface-area-to-volume ratio and their general lack of toxicity. These systems are very versatile and different synthetic methods can result in changes in size, shape, and stability, which can play a key role in the ability of the NPs to catalyze reactions, as well as in determining biodistribution, cellular internalization and other properties relevant to biomedical applications. During the synthesis of AuNPs a stabilizer is required to coat the NP surface avoiding irreversible aggregation of the NPs. Since the stabilizer coats the NP surface, it can also be used to functionalize the NPs with groups specific to the application. The most commonly used stabilizers include alkyl thiols; however, it has been well-documented that these stabilizers lack stability, especially in the human body. Therefore, N-heterocyclic carbene (NHC) ligands have been proposed as an alternative due to their increased stability and ease of functionalization. Despite the well-known catalytic properties and biocompatiability of AuNPs, little work has been done on using AuNPs to catalyze reactions in living cells, for example, unmasking a protected drug to form an active anticancer drug in situ, avoiding damage to healthy cells. Additionally, there have been no examples reported with NHC stabilized AuNPs (NHC@AuNPs) despite their increased stability. Therefore, in this project the NPs will first be synthesized before the addition of a targeting moeity to target cancer cells on the NP surface. These NPs will then be tested as targeted catalysts for reactions in living cells. Additionally, other metals such as Ru, Pt and Ni, will be combined with Au to see if improvements can be made to the catalytic properties, as well as expanding the library of reactions the NPs can catalyze.