Hydrogenated Titanium Oxide Decorated Upconversion Nanoparticles: Facile Laser Modified Synthesis and 808 nm Near-Infrared Light Triggered Phototherapy

Abstract

With multiphoton excited upconversion nanoparticles (UCNPs) as energy transducer, ultraviolet (UV) light responsive titanium dioxide (TiO 2 ) can be triggered indirectly by near-infrared (NIR) light for deep-tissue photodynamic therapy (PDT) through the fluorescence resonance energy transfer (FRET) strategy. Compared to pristine TiO 2 , absorption of hydrogenated black TiO 2 (H-TiO 2 ) in visible (vis) and NIR regions presents a marked improvement in performance, which leads H-TiO 2 to enhance its overall activity. Owing to the light absorption enhancement, the single component H-TiO 2 can be served as vis-driven photosensitizers (PSs) for PDT as well as NIR-triggered photothermal agents (PTAs) for photothermal therapy (PTT) simultaneously. Herein, H-TiO 2 decorated Nd 3+ -sensitized-UCNPs (Nd:UCNPs@H-TiO 2 ) nanocomposites (NCs) were synthesized by Nd:Y 3 Al 5 O 12 (Nd:YAG) pulsed-laser irradiation of Nd:UCNPs@TiO 2 precursors in suspended aqueous solution. Pulsed-laser modified synthesis is the optimum selection for preparing H-TiO 2 to meet the requirement for dispersion of biomaterials. Nd:UCNPs can convert 808 nm light energy to upconverting green emission for activating the attached H-TiO 2 to produce reactive oxygen species (ROS). Meanwhile, H-TiO 2 can directly convert 808 nm light energy to hyperthermia together with infrared photothermal and photoacoustic signals. The Nd:UCNPs@H-TiO 2 NCs exhibit remarkable photoconversion effects as NIRresponsive theranostic agents for accurate diagnosis and efficient phototherapy of tumors.

Two-dimensional metal carbides and nitrides (MXenes): preparation, property, and applications in cancer therapy

“…Light with a specific wavelength activates a PS that accumulates at the tumor site [101]. The activated PS transfers energy to the surrounding oxygen molecules, leading to oxygen reduction and production of reactive oxygen species (ROS), which oxidizes the biological macromolecules leading to tumor reduction, vascular damage, localized acute inflammation, and immune response [102].…”

Fluorescence Detection and Dissociation of Amyloid‐β Species for the Treatment of Alzheimer's Disease

“…Of late, PDT is considered to be a promising modality for treating tumors, [67][68][69][70][71][72][73][74][75][76] glaucoma, and so on [77] because of its advantages, including minimal invasiveness and high spatial selectivity. [80][81][82][83][84][85][86][87][88][89][90][91][92][93][94][95] More importantly, by employing their unique merits, UCNPs have also shown potential application in inhibiting Aβ aggregation. [79] To address these challenges, rare earth upconversion nanoparticles (UCNPs) have been utilized as energy transducers to indirectly activate PS by using NIR light as excitation source.…”

In vivo therapeutic response monitoring by a self-reporting upconverting covalent organic framework nanoplatform

“…To overcome these limitations, herein, we developed an upconverting COF nanoplatform for efficient NIR activated and in situ self-reporting PDT. Based on a lanthanide-doped upconversion nanoparticle (UCNP) core, [42][43][44][45][46][47][48][49][50][51][52][53] we realized the controlled synthesis of nanoscale COFs with various shell thicknesses via core-mediated imine polymerization on the UCNPs, which were termed UCCOFs (Scheme 1a). Aer tailoring the COF shell thickness, the photodynamic efficacy of the UCCOFs was greatly improved, becoming 12.5 times that of irregular COFs.…”