Synthetic swimmers have been increasingly explored. These remarkable self-propelled materials can convert chemical or light energy into locomotion, increasing mixing and accelerating chemical reactions. Asymmetry in particle composition enables movement through a local build-up of reaction products, whereas particle size and geometry control speed and directionality. While motors with dimensions of 100s of nanometers or microns have been widely studied, sub-100 nm devices have been largely neglected because they are harder to make. This research will use the expert manufacturing capabilities of viral biomaterials to overcome these fabrication challenges. The development of such an assembly strategy will enable the spatial and topographical control essential for important biomedical, sensing, and environmental remediation applications. This research will support both mentoring and outreach activities to inspire, recruit, and train a diverse group of scientists and engineers. These activities will strengthen the education of graduate, undergraduate, and middle students.
Viral nanoparticles are monodisperse, self-assembled biomaterials. Their structure and chemistry, including exact shape and site-specific functional groups, is genetically encoded and known with precision. The project objective is to create a shape-changing viral template with broken symmetry that is capable of serving as a platform with which to design and synthesize asymmetric functional nanomaterials. The proposed work will focus on using the size and shape of the transformed viral templates to manipulate the motion of viral nanoparticle-based nanoswimmers. Viral geometry will be converted from filament to rod to spheroid through brief organic solvent exposure. Following these extreme dimensional changes and sidechain packing transitions, differences in surface exposed residues will be evaluated. In addition, the effect of N-terminal amino acid sidechain character on solvent-based transformation, as well as the size and stability of the shape-modified scaffold will be studied. The reduced surface chemistry homogeneity of the shape-changed viruses will be used to synthesize or assemble non-centrosymmetric self-electrophoretic and light-induced self-electrophoretic nanoparticle-based nanoswimmers. Viral-templated nanoparticle trajectory will be explored, rotational and translational diffusion coefficients measured, and motion correlated with nanomaterial size and shape. The proposed studies will improve fundamental understanding of the structure-function relationship associated with geometric tunability of the filamentous virus and particle motion; advance knowledge of biomolecule interactions with and control over non-centrosymmetric nanostructure formation; and enhance viral-templated nanoparticle motion through precise control over template size and shape.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
