The influence of the shape of pathogens on their entry into host cells has been studied intensely. Similarly, different cellular uptake studies using synthetic nanoparticles have proven that their size and shape as well as aspect ratio and surface charge greatly influence cellular internalization pathways and efficiency in a cell-type-specific manner.
Due to their complete addressability and design controllability, DNA origami structures present a unique platform for intracellular applications such as drug delivery, but also to probe complex cellular signaling pathways via receptor-ligand interactions extracellularly. One of our research interests is to use the inherent addressability of DNA origami structures for the controlled arrangement of ligands to study interactions and signaling pathway initiations of immune cells.
A major bottleneck for intracellular applications of DNA origami structures is the requirement of high salt concentrations and ambient temperatures to maintain their structural integrity, as well as a susceptibility to nuclease degradation. Therefore we developed a new method to protect DNA nanostructures with a Silica coating. Silica exhibits excellent biocompatibility, non-toxicity, thermal stability, as well as chemical inertness. Using the DNA origami nanostructures as templates we can now create novel designer Silica nanostructures of various sizes and shapes. Our aim is to understand their interactions with cells (uptake, intracellular behaviour, toxicity) and proteins, esp. enzymes and to identify optimal candidates for further development into biomedical and biocatalytic agents.