Plasmon-Triggered Upconversion Emissions and Hot Carrier Injection for Combinatorial Photothermal and Photodynamic Cancer Therapy
Journal
ACS Applied Materials and Interfaces
Journal Volume
13
Journal Issue
49
Pages
58422-58433
Date Issued
2021
Author(s)
Abstract
Despite the unique ability of lanthanide-doped upconversion nanoparticles (UCNPs) to convert near-infrared (NIR) light to high-energy UV-vis radiation, low quantum efficiency has rendered their application unpractical in biomedical fields. Here, we report anatase titania-coated plasmonic gold nanorods decorated with UCNPs (Au NR@aTiO2@UCNPs) for combinational photothermal and photodynamic therapy to treat cancer. Our novel architecture employs the incorporation of an anatase titanium dioxide (aTiO2) photosensitizer as a spacer and exploits the localized surface plasmon resonance (LSPR) properties of the Au core. The LSPR-derived near-field enhancement induces a threefold boost of upconversion emissions, which are re-absorbed by neighboring aTiO2 and Au nanocomponents. Photocatalytic experiments strongly infer that LSPR-induced hot electrons are injected into the conduction band of aTiO2, generating reactive oxygen species. As phototherapeutic agents, our hybrid nanostructures show remarkable in vitro anticancer effect under NIR light [28.0% cancer cell viability against Au NR@aTiO2 (77.3%) and UCNP@aTiO2 (98.8%)] ascribed to the efficient radical formation and LSPR-induced heat generation, with cancer cell death primarily following an apoptotic pathway. In vivo animal studies further confirm the tumor suppression ability of Au NR@aTiO2@UCNPs through combinatorial photothermal and photodynamic effect. Our hybrid nanomaterials emerge as excellent multifunctional phototherapy agents, providing a valuable addition to light-triggered cancer treatments in deep tissue. ? 2021 American Chemical Society.
Subjects
localized surface plasmon resonance
photosensitizer
phototherapy
titanium dioxide
upconversion
Cell death
Hot electrons
Infrared devices
Nanorods
Photodynamic therapy
Plasmonics
Titanium dioxide
Cancer cells
Hot carrier injection
Localized surface plasmon resonance
Near infrared light
Photo-thermal
Photosensitiser
Phototherapy
Up-conversion
Up-conversion emission
Upconversion nanoparticles
Photosensitizers
Type
journal article