Dye-sensitized lanthanide-doped upconversion nanoparticles

Abstract

Lanthanide-doped upconversion nanoparticles (UCNPs) are promising for applications as wide as biological imaging, multimodal imaging, photodynamic therapy, volumetric displays, and solar cells. Yet, the weak and narrow absorption of lanthanide ions poses a fundamental limit of UCNPs to withhold their brightness, creating a long-standing hurdle for the field. Dye-sensitized UCNPs are emerging to address this performance-limiting problem, yielding up to thousands-fold brighter luminescence than conventional UCNPs without dye sensitization. In their configuration, organic dyes with spectrally broad and intense absorption are anchored to the surface of UCNPs to harvest the excitation light energy, which is then transferred via Förster and/or Dexter mechanisms across the organic/inorganic interface to the lanthanides incorporated in UCNPs (with or devoid of a shell) to empower efficient upconversion. This tutorial review highlights recent progress in the development of dye sensitized UCNPs, with an emphasis on the theory of energy transfer, the geometric classification of the dye sensitized core and core/shell nanocrystals, and their emerging photonic and biophotonic applications. Opportunities and challenges offered by dye sensitized UCNPs are also discussed.

Duel‐Responsive Hybrid Nanoparticle with Energy Transfer Modulated Near Infrared Emission

“…[13] Moreover, organicinorganic hybrid with different organic dyes capped onto surfaces of Ln-doped NPs demonstrated improved visible emission have found broad application in sensing and detection, making them attractive for bio-medicine and relevant applications. [15,16] In the present work, we show sensitized NIR emission in an organic/inorganic hybrid NP upon visible light excitation. The hybrid NPs are made up of fluoride (β-NaYF 4 ) NPs activated with a typical NIR emitting ion, Nd 3 + , and surface capping agent of π-conjugated oligomer OFBT, which gives strong visible emission upon blue light excitation.…”

“…For instance, inorganic fluoride NPs capped with organic dye molecules have demonstrated large enhancement in upconversion emission intensity and such systems enables the broadband excitation of the UC emission with excitation bandwidth over 100 nm . Moreover, organic‐inorganic hybrid with different organic dyes capped onto surfaces of Ln‐doped NPs demonstrated improved visible emission have found broad application in sensing and detection, making them attractive for bio‐medicine and relevant applications …”

Remote Light‐Responsive Nanocarriers for Controlled Drug Delivery: Advances and Perspectives

“…Third, the excitations of lanthanide‐UCNPs are currently limited by 980 and 808 nm. New strategy, such as dye‐sensitized upconversion will be promising to enhance the emission of UCL and extend the excitation light source, thus contributing to future development of light triggered drug delivery systems.…”

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.…”