Cowpea mosaic virus (CPMV) is currently in the development pipeline for multiple biomedical applications, including cancer immunotherapy.

Nanoparticle-based pesticide delivery systems have emerged to decrease the environmental and health impact of pesticides while increasing their efficacy. A majority of nanopesticides in the development pipeline are synthetic materials, some of which present their own environmental risks. We propose the development of naturally occurring nanomaterials, namely plant viruses such as tobacco mild green mosaic virus (TMGMV), for the delivery of pesticides. We and others have previously shown that plant virus-based nanoparticles have favorable soil mobility properties and thus could offer new avenues for the delivery of pesticides to target root-feeding pests. Toward the application of plant virus-based vectors as pesticide delivery agents, we optimized inactivation methods. We report the successful inactivation of TMGMV using 10 J cm −2 of ultraviolet light, 1.5 M βPL, or 1 M formalin; the lack of infectivity was confirmed using Nicotiana tabacum Tennessee 86, N. tabacum Samsun nn, and tropical soda apple (Solanum viarum).

Engineered living materials (ELMs) that incorporate living organisms and synthetic materials enable advanced functional properties. Here, we seek to create plant cyborgs by combining plants or plant tissues with stimuli-responsive polymeric materials. Plant tissues with integrated shape control may find applications in regenerative medicine, and the shape control of living plants enables another dimension of adaptability and response to environmental threats, which can be applied to next-generation precision farming. In this work, we develop chemistry to integrate stimuli-responsive poly­(N-isopropylacrylamide) (PNIPAM) hydrogels with decellularized plant tissues assisted by 3D printing. We demonstrate programmable shape morphing in response to thermal cues and ultraviolet (UV) light. Specifically, by taking advantage of the extrusion-based 3D printing method, we deposit nanocomposite PNIPAM precursors onto silane-treated decellularized leaf surface with prescribed shapes and spatial control. When subjected to external stimuli, the strain mismatch generated between the swellable nanocomposite PNIPAM and nonswellable decellularized leaf enables folding and bending to occur. This strategy to integrate the plant tissues with stimuli-responsive hydrogels allows the control of leaf morphology, opening avenues for plant-based biosensors and soft actuators to enhance food security; such materials also may find applications in biomedicine as tissue-engineering scaffolds.

Filamentous nanomaterials are flexible with a high aspect ratio, conferring unique mechanical, electromagnetic, and optical properties; promoting tissue penetration; and allowing the formation of hierarchical superstructures. The fabrication of synthetic nanofilaments with uniform properties is challenging, but this can be addressed by the use of filamentous plant viruses such as potato virus X (PVX), which are produced as monodisperse structures from a genetic template. To take advantage of PVX without risks to agriculture and the environment, it is necessary to inactivate the virus efficiently without disrupting its chemical and material properties. Herein, we report experiments showing that PVX can be completely inactivated by exposure to UV irradiation (0.5 J cm–2) or chemical treatment (1 mM β-propiolactone or 10 mM formalin) without interfering with the chemical addressability of lysine or cysteine residues, which are typically used as conjugation handles for virus nanoparticle functionalization.