Enhanced Nanobubble\nFormation: Gold Nanoparticle Conjugation\nto Qβ Virus-like Particles

Plasmonic gold nanostructures are a prevalent tool in\nmodern hypersensitive\nanalytical techniques such as photoablation, bioimaging, and biosensing.\nRecent studies have shown that gold nanostructures generate transient\nnanobubbles through localized heating and have been found in various\nbiomedical applications. However, the current method of plasmonic\nnanoparticle cavitation events has several disadvantages, specifically\nincluding small metal nanostructures (≤10 nm) which lack size\ncontrol, tuneability, and tissue localization by use of ultrashort\npulses (ns, ps) and high-energy lasers which can result in tissue\nand cellular damage. This research investigates a method to immobilize\nsub-10 nm AuNPs (3.5 and 5 nm) onto a chemically modified thiol-rich\nsurface of Qβ virus-like particles. These findings demonstrate\nthat the multivalent display of sub-10 nm gold nanoparticles (AuNPs)\ncaused a profound and disproportionate increase in photocavitation\nby upward of 5–7-fold and significantly lowered the laser fluency\nby 4-fold when compared to individual sub-10 nm AuNPs. Furthermore,\ncomputational modeling showed that the cooling time of QβAuNP\nscaffolds is significantly extended than that of individual AuNPs,\nproving greater control of laser fluency and nanobubble generation\nas seen in the experimental data. Ultimately, these findings showed\nhow QβAuNP composites are more effective at nanobubble generation\nthan current methods of plasmonic nanoparticle cavitation.