Black Hole Quencher-Enhanced Plasmonic Photothermal Conversion

Area of Science:

• Thermoplasmonics
• Nanotechnology
• Biomedical Engineering

Background:

• Improving photothermal conversion efficiency (PCE) in plasmonic nanostructures is crucial but challenging.
• Plasmonic nanostructures convert light into heat, with applications in therapy and diagnostics.

Purpose of the Study:

• To develop a universal method for dramatically improving the PCE of plasmonic nanostructures.
• To investigate the synergistic effects of combining plasmonic nanostructures with black hole quencher (BHQ) molecules.

Main Methods:

• Immobilizing nonfluorescent resonant BHQ molecules to matched metal nanostructures to create plasmonic hybrids.
• Irradiating the hybrids with laser light to induce charge/energy transfer.
• Testing photothermal efficacy and PCE of the hybrids compared to individual components.

Main Results:

• The PCE of BHQ-plasmon hybrids was significantly higher (approximately three times) than the sum of individual plasmon and BHQ components.
• The hybrid nanoparticles exhibited a nonlinear response to plasmon fields, unlike fluorophores.
• Enhanced PCE up to 69.1% in the NIR-II region was achieved, attributed to plasmonic nanoparticles, BHQ, and their mutual interaction.

Conclusions:

• The add-on BHQ molecule strategy provides a universal method to dramatically enhance plasmonic photothermal conversion.
• BHQ-plasmon hybrids enable highly efficient photothermal conversion for in vitro and in vivo cancer hyperthermia ablation.
• This strategy demonstrates broad generalizability across various plasmonic nanostructures and BHQs.