Characterising nanoparticle surface adsorption and intercalation for morphology control and cellular delivery
This project seeks to explore the nature of surface interactions between nanoparticles and inorganic or biological adsorbates in a water environment. Such surface interactions have many implications for the functional application of nanoparticles. In the case of short-strand DNA or RNA adsorption, this interaction controls the relative stability of surface adsorbed and/or intercalated oligonucleotides and is critical to understanding how LDH (layered double hydroxide) nanoparticles facilitate cellular delivery. In the case of inorganic surface adsorbates, evidence suggests that such adsorbates can control the relative stability of different crystal faces, hence impacting on the morphology and reactivity of the synthesised nanoparticles.
Major achievements and research highlights
We have been working for several years to build an efficient molecular dynamics platform for exploration of structure and dynamics of the complex DNA/LDH nanoparticle complexes in an explicit water environment. This work, which involves many challenges to integrate inorganic and biological forcefields into a single efficient platform is now coming to fruition. We have published an initial paper demonstrating the approach by modelling nanoparticle interactions with inorganic chloride and nitrate counter-ions, comparing with extant experimental data. Simulations of short-strand DNA interactions with double layered nanoparticle models – both surface and intercalate geometries – are presently underway and were presented at the ICONN meeting in February 2008.
Preliminary investigations of the effect of inorganic surface adsorbates on the relative stability of different cyrstallographic faces of TiO2 nanoparticles – impacting on morphology of the synthesised particles – have yielded fascinating results in remarkable concert with experiment. This work is presently submitted to the high impact journal Nature Materials.
Future plans and directions
A preliminary benchmark publication on LDH nanoparticles interacting with small inorganic counterions Cl- and NO3- is in submission stages. Several further publications on the short DNA/RNA strands are anticipated in the coming year. We will also explore the effect of differing morphology of nanoparticles on stability and interactions – prompted by intriguing experimental results within the Centre currently in preparation for publication.
