Using the macromolecules which exist in biological systems can be a robust way to design functional materials. These bio-inspired and bio-derived materials can be thermoresponsive, have a high strength to mass ratio, or serve as a wet adhesive, among other applications. To advance the design of bio-inspired materials, a new focus lies on engineered living materials – materials that retain a living component of the system from which they are derived. This opens the door to functions such as self-replication, self-healing, and biosensing in these materials. These systems achieve this function by incorporating living cell cultures, virus particles, and plant scaffolds.<br/><br/>Tobacco mild green mosaic virus (TMGMV) is rod-shaped nucleoprotein assembly with defined dimensions of 300 nm x 18 nm, and is approved as an herbicide by the US Food and Drug Administration. This plant virus has been previously demonstrated to undergo RNA-templated assembly to produce a hollow nanotube the individual coat proteins templated on the RNA. In this work, we use TMGMV as a platform for ELMs. We demonstrate that TMGMV can undergo a concentration-dependent thermal transition to spherical nanoparticles (SNPs) of several sizes ranging from tens of nanometers to several microns. We develop a phase space of temperature, concentration, and incubation time to show how the morphology of the particles change during the synthesis and provide rationale behind the mechanism of transformation. We characterize the resulting SNPs by gel electrophoresis and size-exclusion chromatography. SNPs are then functionalized with active ingredient through encapsulation or bioconjugation. The degree of loading is confirmed by mass spectrometry, fluorescence measurements, and electrophoresis. The SNPs demonstrate potential as a living material for drug delivery and precision agriculture applications. Future studies will investigate how to incorporate self-replication or continuous manufacturing into these materials and the transport behavior of the SNPs in soil and biological systems.

Thermal transformation of rod-shaped viruses into spherical nanoparticles for precision agriculture and drug delivery

ACS Spring 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.