In this study,α-TeO2：Ho3＋/Yb3＋,α-TeO2：Eu3＋ andα-TeO2：Ho3＋/Yb3＋/Eu3＋ nanoparticles were prepared via a simple hydrothermal process. The up- and down-conversion properties of the as-prepared nanoparticles we...In this study,α-TeO2：Ho3＋/Yb3＋,α-TeO2：Eu3＋ andα-TeO2：Ho3＋/Yb3＋/Eu3＋ nanoparticles were prepared via a simple hydrothermal process. The up- and down-conversion properties of the as-prepared nanoparticles were tested at room temperature un-der a near-infrared photo source （980 nm） and UV-vis photo source, respectively.The results indicated thatα-TeO2 NPs were a kind of outstanding host material for both up- and down-conversion luminescence. Theα-TeO2：Ho3＋/Yb3＋nanoparticles showed sharp up-conversion emission at 545 and 660 nm under 980 nm excitation, ascribed to the5S2→5I8 and5F5→5I8（Ho3＋） transitions, and weaker down-conversion emission at 545 nm under 455 nm excitation, ascribed to the5S2→5I8（Ho3＋） transitions. Theα-TeO2：Eu3＋nanoparticles showed strong down-conversion emission at 592 and 615 nm under 395 nm excitation, attributed to the5D0→7F1 and 5D0→7F2 （Eu3＋） transitions. Possessing the advantages of these two luminescent materials, the as-prepared tri-doped samples ofα-TeO2：0.5Ho3＋/10Yb3＋/3Eu3＋ （mol.%）nanoparticles could successfully emit visible light via both up- and down-conversion modes.展开更多
Versatile optimization of the synthesis method and composition of Yb^3＋ and Tm^3＋ co-doped CaF2 nanoparticles as well as a novel biofunctionalization method were developed and evaluated. Through multistep synthesis,...Versatile optimization of the synthesis method and composition of Yb^3＋ and Tm^3＋ co-doped CaF2 nanoparticles as well as a novel biofunctionalization method were developed and evaluated. Through multistep synthesis, the luminescence intensity of the Tm3. activator was enhanced by more than 10-fold compared to standard one-step synthesis. The proposed methods were used to homogenously distribute the doping ions within the nanoparticle＇s volume and thus reduce luminescence quenching. Optimization of dopant ions concentration led to the selection of the most efficient visible and near-infrared up-converting nanoparticles, which were CaF2 doped with 10% Yb^3＋ 0.05% Tm^3＋ and 20% Yb3. 0.5% Tm^3＋, respectively. To illustrate the suitability of the synthesized nanoparticles as bio-labels, a dedicated biofunctionalization method was used, and the nanoparticles were applied for labeling and imaging of Candida albicans cells. This method shows great promise because of extremely low background and high specificity because of the presence of the attached molecules.展开更多
The nanoplatforms based on upconversion nanoparticles(UCNPs)have shown great promise in amplified photodynamic therapy(PDT)triggered by near-infrared(NIR)light.However,their practical in vivo applications are hindered...The nanoplatforms based on upconversion nanoparticles(UCNPs)have shown great promise in amplified photodynamic therapy(PDT)triggered by near-infrared(NIR)light.However,their practical in vivo applications are hindered by the overheating effect of 980 nm excitation and low utilization of upconversion luminescence(UCL)by photosensitizers.To solve these defects,core-satellite metal-organic framework@UCNP superstructures,composed of a single metal-organic framework(MOF)NP as the core and Nd3+-sensitized UCNPs as the satellites,are designed and synthesized via a facile electrostatic self-assembly strategy.The superstructures realize a high co-loading capacity of chlorin e6(Ce6)and rose bengal(RB)benefitted from the highly porous nature of MOF NPs,showing a strong spectral overlap between maximum absorption of photosensitizers and emission of UCNPs.The in vitro and in vivo experiments demonstrate that the dual-photosensitizer superstructures have trimodal(magnetic resonance(MR)/UCL/fluorescence(FL))imaging functions and excellent antitumor effectiveness of PDT at 808 nm NIR light excitation,avoiding the laser irradiation-induced overheating issue.This study provides new insights for the development of highly efficient PDT nanodrugs toward precision theranostics.展开更多
基金supported by the National Natural Science Foundation of China(21075053)the"Challenge Cup"Undergraduate Extra-curriculum Academics,Science and Technology Works Competition and Student's Platform for Innovation and Entrepreneurship Training Program(201410559056)in Jinan University
文摘In this study,α-TeO2：Ho3＋/Yb3＋,α-TeO2：Eu3＋ andα-TeO2：Ho3＋/Yb3＋/Eu3＋ nanoparticles were prepared via a simple hydrothermal process. The up- and down-conversion properties of the as-prepared nanoparticles were tested at room temperature un-der a near-infrared photo source （980 nm） and UV-vis photo source, respectively.The results indicated thatα-TeO2 NPs were a kind of outstanding host material for both up- and down-conversion luminescence. Theα-TeO2：Ho3＋/Yb3＋nanoparticles showed sharp up-conversion emission at 545 and 660 nm under 980 nm excitation, ascribed to the5S2→5I8 and5F5→5I8（Ho3＋） transitions, and weaker down-conversion emission at 545 nm under 455 nm excitation, ascribed to the5S2→5I8（Ho3＋） transitions. Theα-TeO2：Eu3＋nanoparticles showed strong down-conversion emission at 592 and 615 nm under 395 nm excitation, attributed to the5D0→7F1 and 5D0→7F2 （Eu3＋） transitions. Possessing the advantages of these two luminescent materials, the as-prepared tri-doped samples ofα-TeO2：0.5Ho3＋/10Yb3＋/3Eu3＋ （mol.%）nanoparticles could successfully emit visible light via both up- and down-conversion modes.
文摘Versatile optimization of the synthesis method and composition of Yb^3＋ and Tm^3＋ co-doped CaF2 nanoparticles as well as a novel biofunctionalization method were developed and evaluated. Through multistep synthesis, the luminescence intensity of the Tm3. activator was enhanced by more than 10-fold compared to standard one-step synthesis. The proposed methods were used to homogenously distribute the doping ions within the nanoparticle＇s volume and thus reduce luminescence quenching. Optimization of dopant ions concentration led to the selection of the most efficient visible and near-infrared up-converting nanoparticles, which were CaF2 doped with 10% Yb^3＋ 0.05% Tm^3＋ and 20% Yb3. 0.5% Tm^3＋, respectively. To illustrate the suitability of the synthesized nanoparticles as bio-labels, a dedicated biofunctionalization method was used, and the nanoparticles were applied for labeling and imaging of Candida albicans cells. This method shows great promise because of extremely low background and high specificity because of the presence of the attached molecules.
基金This work was financially supported by National Natural Science Foundation of China(NSFC,Nos.21601140 and 21871214)the Fundamental Research Funds for the Central Universities,and Open Research Fund of State Key Laboratory of Bioelectronics.
文摘The nanoplatforms based on upconversion nanoparticles(UCNPs)have shown great promise in amplified photodynamic therapy(PDT)triggered by near-infrared(NIR)light.However,their practical in vivo applications are hindered by the overheating effect of 980 nm excitation and low utilization of upconversion luminescence(UCL)by photosensitizers.To solve these defects,core-satellite metal-organic framework@UCNP superstructures,composed of a single metal-organic framework(MOF)NP as the core and Nd3+-sensitized UCNPs as the satellites,are designed and synthesized via a facile electrostatic self-assembly strategy.The superstructures realize a high co-loading capacity of chlorin e6(Ce6)and rose bengal(RB)benefitted from the highly porous nature of MOF NPs,showing a strong spectral overlap between maximum absorption of photosensitizers and emission of UCNPs.The in vitro and in vivo experiments demonstrate that the dual-photosensitizer superstructures have trimodal(magnetic resonance(MR)/UCL/fluorescence(FL))imaging functions and excellent antitumor effectiveness of PDT at 808 nm NIR light excitation,avoiding the laser irradiation-induced overheating issue.This study provides new insights for the development of highly efficient PDT nanodrugs toward precision theranostics.
文摘掺杂稀土元素的上转换纳米材料(upconversion nanoparticles,UCNPs)作为新型无机发光材料,因其具有良好的荧光稳定性及生物相容性,并可避免生物材料的自发荧光,在生物传感领域具有明显优势。基于上转换材料的荧光共振能量转移(fluorescence resonance energy transfer,FRET)体系在生物检测方面的应用也越来越广泛。本文就上述转换材料为基础的FRET体系在生物毒素、激素、蛋白质、核酸、细菌等生物检测方面的应用及未来展望作一综述。
