Plasmonic Activation of Macromolecular Assemblies

The ability to encapsulate and release molecules on-demand from smart carrier vesicles would be transformative for a wide range of applications. Polymersomes are a class of synthetic vesicles which self-assemble from diblock copolymer amphiphiles, resulting in an aqueous lumen and thick bilayer membrane; however, vesicles assembled from robust poly(butadiene)-b-poly(ethylene oxide) are not inherently stimuli responsive. Herein, we demonstrate that plasmonic activation of gold nanoparticles can be utilized to induce structural alterations in nearby macromolecular structures. Hydrophobic gold nanoparticles can be incorporated into the membrane of micron and nano-scale polymersomes to serve as photosensitizers, rendering the vesicles responsive to pulsed laser irradiation congruent with their localized surface plasmon resonance. Studies have demonstrated that membrane disruption resulting in cargo release can range from transient poration to complete rupture, depending on parameters such as laser pulse duration and energy. Interestingly, it has been noted that ligands utilized to render nanoparticles hydrophobic play a large role in their organization within the polymersome membrane. We seek to gain control over nanoparticle organization within the membrane via ligand-ligand interactions, as well as outside of the membrane via DNA-origami attachment.