Applying High Throughput Experimentation Techniques to Assemble Particles of Arbitrary Shapes Using DNA Bridges

Future technological developments in fields including alternative energy and medicine require next-generation materials. Synthesizing each new material requires exploring a multi-dimensional parameter space. Developing laboratory automation tools for automating lab procedures and data analysis will be key to efficient discovery of optimal, novel materials. Some automation tools utilized in this work include automated sample loading and analysis for both Small Angle X-ray Scattering (SAXS) and Dynamic Light Scattering (DLS), and a newly constructed sonication robot.

The goals of this project are to apply these lab automation tools to construct and characterize crystalline structures of particles of arbitrary shapes encapsulated in a lipid membrane and connected with DNA bridges. With high throughput methods, the impact of design parameters on the crystal structure can also be determined. Parameters of interest in the self-assembly of particles of any geometry include the ratio of lipid types in the membrane and the nanoparticle surface area to membrane surface area ratio.

The first step in constructing a new crystalline material is embedding the nanoparticles in a lipid membrane of optimal composition. Next, the cholesterol end of synthesized DNA-cholesterol fragments embeds in the membrane and complementary DNA fragments are added to connect the nanoparticles. Heating the solution above the melting temperature of the complementary regions of the DNA fragments and dropping the temperature slowly encourages crystal formation. The aggregates formed are analyzed via SAXS before and after DNA bridge addition and heating to determine if crystals are formed.

This technique has been used on spherical silica particles previously, and it is hypothesized that it can be applied to self-assemble crystals comprised of other particle geometries. Preliminary results from this project are presented here.