Hydrophobic Cargo Encapsulation into Virus Protein Cages by Self-Assembly in an Aprotic Organic Solvent.

While extensive studies of virus capsid assembly in environments mimicking conditions have led to an understanding of the thermodynamic driving forces at work, applying this knowledge to virus assembly in other solvents than aqueous buffers has not been attempted yet. In this study, Brome mosaic virus (BMV) capsid proteins were shown to preserve their self-assembly abilities in an aprotic polar solvent, dimethyl sulfoxide (DMSO). This facilitated protein cage encapsulation of nanoparticles and dye molecules that favor organic solvents, such as β-NaYF-based upconversion nanoparticles and BODIPY dye.