(244g) Multilayered Ordered Arrays Self-Assembled from a Mixed Population of Nanoparticles

A key synthesis challenge in the design of bio-inspired materials with tailored structure is to control the spatial arrangement of individual building blocks when assembling multiple types of components. Using coarse-grained molecular dynamics simulations and SAXS measurements, we demonstrate self-assembly of multilayered, ordered protein arrays from a mixed population of building blocks, where each layer is composed of the same type of building block. Using virus-like particles derived from bacteriophage P22 as building blocks, we show that a 1:1 mixture of two types of virus-like particles selectively assembles into core-shell structures in the presence of oppositely charged dendrimers during a gradual lowering of the ionic strength of the solution. Different types of virus-like particles possess negatively-charged surfaces characterized with different magnitudes of surface charge. We demonstrate that, by tuning the ionic strength, these distinct surface charges can be utilized to induce assembly of only one selected type of building block in the presence of building blocks of all types. This assembly is shown to be reversible and sensitive to the rate of change of the ionic strength. Extensions to mixtures of different stoichiometric ratios and more than 2 types of building blocks are discussed. Our findings establish a simple and versatile bottom-up strategy to synthesize multilayered, ordered materials by controlling the spatial arrangement of multiple types of nanoscale building blocks in a one-pot fabrication.