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Helena Oliveira, Artur Bednarkiewicz, Andreas Falk, Eleonore Fröhlich, Darja Lisjak, Adriele Prina-Mello, Susanne Resch, Christa Schimpel, Ivana Vinković Vrček, Edyta Wysokińska, Hans H Gorris
The unique photoluminescent properties of upconversion nanoparticles (UCNPs) have attracted worldwide research interest and inspired many bioanalytical applications. The anti-Stokes emission with long luminescence lifetimes, narrow and multiple absorption and emission bands, and excellent photostability enable background-free and multiplexed detection in deep tissues. So far, however, in vitro and in vivo applications of UCNPs are restricted to the laboratory use due to safety concerns. Possible harmful effects may originate from the chemical composition but also from the small size of UCNPs...
December 10, 2018: Advanced Healthcare Materials
Shikai Liu, Wenting Li, Shili Gai, Guixin Yang, Chongna Zhong, Yunlu Dai, Fei He, Piaoping Yang, Yung Doug Suh
Near-infrared (NIR) light-induced imaging-guided cancer therapy has been studied extensively in recent years. Herein, we report a novel theranostic nanoplatform by modifying polyoxometalate (POM) nanoclusters onto mesoporous silica-coated upconversion nanoparticles (UCNPs), followed by loading doxorubicin (DOX) in the mesopores and coating a folate-chitosan shell onto the surface. In this nanoplatform, the core-shell structured UCNPs (NaYF4:Yb,Er@NaYF4:Yb,Nd) showed special upconverting luminescence (UCL) when irradiated with high-penetration 808 nm NIR light, and the doped Yb and Nd ions endowed the sample with CT imaging properties, thus achieving a dual-mode imaging function...
December 10, 2018: Biomaterials Science
Antonín Hlaváček, Matthias Jürgen Mickert, Tero Soukka, Satu Lahtinen, Terhi Tallgren, Nadezda Pizurova, Anna Król, Hans H Gorris
The performance of photon-upconversion nanoparticles (UCNPs) as background-free luminescent labels in bioanalytical applications strongly depends on the preparation of well-defined and water-dispersible nanoconjugates. We have exploited the separation power of agarose gel electrophoresis to purify milligram amounts of homogeneous UCNPs covered with carboxylated silica, biotin or streptavidin with recovery rates of 30 to 50%. Clusters containing discrete numbers of UCNPs were isolated from the gel and reanalyzed by agarose gel electrophoresis, single nanoparticle upconversion microscopy and additional complementary methods...
December 10, 2018: Analytical Chemistry
Ruichan Lv, Miao Feng, Wolfgang J Parak
Up-conversion nanoparticles (UCNP) under near-infrared (NIR) light irradiation have been well investigated in the field of bio-imaging. However, the low up-conversion luminescence (UCL) intensity limits applications. Plasmonic modulation has been proposed as an effective tool to adjust the luminescence intensity and lifetime. In this study discrete dipole approximation (DDA) was explored concerning guiding the design of UCNP@mSiO₂-Au structures with enhanced UCL intensity. The extinction effects of gold shells could be changed by adjusting the distance between the UCNPs and the Au NPs by synthesized tunable mesoporous silica (mSiO₂) spacers...
November 29, 2018: Nanomaterials
Pounraj Thanasekaran, Chih-Hang Chu, Sheng-Bo Wang, Kuan-Yu Chen, Hua-De Gao, Mandy Manchi Lee, Shih-Sheng Sun, Jui-Ping Li, Jiun-Yu Chen, Jen-Kun Chen, Yu-Hsu Chang, Hsien-Ming Lee
Photodynamic therapy (PDT) is a non-invasive medical technology that has been applied in cancer treatment where it is accessible by direct or endoscope-assisted light irradiation. To lower phototoxicity and increase tissue penetration depth of light, great effort has been focused on developing new sensitizers that can utilize red or near-infrared (NIR) light for the past decades. Lanthanide-doped upconversion nanoparticles (UCNPs) have a unique property to transduce NIR excitation light to UV-Vis emission efficiently...
November 30, 2018: ACS Applied Materials & Interfaces
Yibing Shi, Qingyun Liu, Wei Yuan, Meng Xue, Wei Feng, Fuyou Li
Overdose of Cu2+ is associated with multiple diseases, such as Wilson disease, Parkinson disease and Alzheimer disease. Therefore, the detections of Cu2+ in vivo and in vitro are meaningful. Near-infrared fluorescent probes are commonly applied for the detection of Cu2+ in real time. With mono detection signal provided, these probes are not persuasive when applied to complicated biological environments, such as cells and animals. In this report, we conjugated the organic fluorescent probe CYDAC16 with the UCNPs (Lanthanide-doped upconversion nanoparticles) to develop a ratiometric luminescent probe for Cu2+...
November 28, 2018: ACS Applied Materials & Interfaces
Yujing Zuo, Minggang Tian, Jie Sun, Tingxin Yang, Yu Zhang, Weiying Lin
Discriminating of live and apoptotic cells is a crucial task in the research of pharmacology, biology, pathology, and medicine science. Recently, up conversion (UC) luminescent materials have appealed much attention due to their unique ability to convert low energy excitation photons to high energy ones. However, UC fluorescence has not been employed in the field of discriminating of live and apoptotic cells. We presented a facile, and cost-less Stöber method to fabricate robust silicon na-noparticles (SiO2 UCNPs) exhibiting several merits, such as narrow size distribution, and UC luminescence...
November 26, 2018: Analytical Chemistry
Xuefeng Li, Chunya Qian, Runjie Shen, Hui Xiao, Weishi Zhao, Song Ye
A new type of fluorescence fiber optic temperature sensor based on the detection of fluorescence intensity ratio (FIR) is proposed. Benefited from the temperature-dependent characteristic of upconversion luminescence (UCL), it can be applied in fiber optic temperature sensors. Rare earth doped upconversion nanoparticles (UCNPs) NaYF4 :Er3+ ,Yb3+ are embedded in a multi-mode quartz fiber through the technology of fiber fusion as the sensing unit of temperature sensors. A 980 nm laser is used to stimulate UCL in a temperature range from 40 °C to 100 °C...
November 12, 2018: Optics Express
Rafia Rafique, Seung Hoon Baek, Chan Yeong Park, Sung-Jin Chang, Anam Rana Gul, Siyoung Ha, Thang Phan Nguyen, Hyeongyeol Oh, Seungwook Ham, Muhammad Arshad, Hohjai Lee, Tae Jung Park
Advancements in the fabrication of upconversion nanoparticles (UCNPs) for synthetic control can enable a broad range of applications in biomedical systems. Herein, we experimentally verified the role of the hydrothermal reaction (HR) time in the synthesis of NaYF4 :20%Yb3+ /3%Er3+ UCNPs on their morphological evolution and phase transformation at different temperatures. Characterizations of the as-prepared UCNPs were conducted using X-ray diffraction (XRD), electron microscopy and spectroscopy, and thermogravimetric and upconversion (UC) luminescence analysis...
November 20, 2018: Scientific Reports
Yanyan Li, Li Zhao, Meng Xiao, Yimin Huang, Binghai Dong, Zuxun Xu, Li Wan, Wenlu Li, Shimin Wang
Extending the spectral absorption of organic-inorganic mixed-cation perovskite solar cells (PSCs) from visible light to the near-infrared (NIR) range minimizes the nonabsorption loss of solar photons. Few studies have focused on the application of high-fluorescence NaYbF4:Ho3+ upconversion nanoparticles (UCNPs) in solar cells. In this study, NaYbF4:Ho3+ UCNPs were successfully prepared using a solvothermal method. We incorporated the NaYbF4:Ho3+ UCNPs into ZrO2 as the scaffold layer for FA0.4MA0.6PbI3 perovskite solar cells...
November 29, 2018: Nanoscale
Kuikui Zhang, Qi Zhao, Shirong Qin, Yang Fu, Runze Liu, Jinfang Zhi, Chongxin Shan
A multifunctional nanoplatform with simultaneous imaging and therapeutic capacities has been fabricated by covalently conjugating nanodiamonds (NDs) with upconversion NaYF4 :Yb,Er nanoparticles (UCNPs). Green emission can be observed for the UCNP-NDs composites under 980 nm excitation, and in vitro imaging was carried out towards HeLa cells. The UCNP-NDs also shows good drug storage capability toward anticancer drug doxorubicin (Dox) and exhibits significant pH-dependent drug-release behavior. Dox-loaded UCNP-NDs shows higher therapy efficiency towards Hela cells than free Dox when the equivalent concentration of the Dox is more than 10 μg/mL...
November 10, 2018: Journal of Colloid and Interface Science
Ananda Das, Chenchen Mao, Suehyun Cho, Kyoungsik Kim, Wounjhang Park
Rare-earth activated upconversion nanoparticles (UCNPs) are receiving renewed attention for use in bioimaging due to their exceptional photostability and low cytotoxicity. Often, these nanoparticles are attached to plasmonic nanostructures to enhance their photoluminescence (PL) emission. However, current wet-chemistry techniques suffer from large inhomogeneity and thus low enhancement is achieved. In this paper, we report lithographically fabricated metal-insulator-metal (MIM) nanostructures that show over 1000-fold enhancement of their PL...
November 16, 2018: Nature Communications
Miao Feng, Ruichan Lv, Liyang Xiao, Bo Hu, Shouping Zhu, Fei He, Piaoping Yang, Jie Tian
Generally, luminescence quenching at high doping concentrations typically limits the concentration of doped ions in the lanthanide material to less than 0.05-20 mol %, and this is still a major hindrance in designing nanoplatforms with improved brightness. In this research, a nanoplatform capable of dual-modal imaging and synergetic antitumor cells therapy was designed. NaYF4 : x%Er@NaXF4 ( x = 5, 25, 50, and 100; X = Lu and Y) core@shell nanoparticles with Er3+ ion concentration up to 100 mol % were synthesized, and the luminescence properties under near-infrared (NIR) excitation were detected...
November 16, 2018: Inorganic Chemistry
Hossein Najafiaghdam, P Papageorgiou, Nicole A Torquato, Cheryl A Tajon, Hui Zhang, Catherine Park, Bernhard Boser, Bruce E Cohen, Mekhail Anwar
Optimal cancer therapy requires targeted and individualized treatment of all tumor cells, including both gross and microscopic disease. Intraoperatively hard to visualize and often left behind, microscopic foci of residual cancer cells significantly increase the risk of cancer recurrence and treatment failure rates. Fluorescently-tagged targeted molecular labels are employed to guide surgery, but conventional fluorescent intraoperative imagers suffer from lack of sensitivity and maneuverability, limiting practicality in small tumor cavities owing to their cumbersome sizes driven by optics...
July 2018: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
Lisa Marie Wiesholler, Christa Genslein, Alexandra Schroter, Thomas Hirsch
A nanoengineered interface fabricated by self-assembly enables the online determination of vitamin B12 via a simple luminescence readout in serum without any pretreatment. The interplay of Tm3+ -doped NaYF4 nanoparticles (UCNPs) and a gold nanotriangle array prepared by nanosphere lithography on a glass slide is responsible for an efficient NIR to UV upconversion. Hot spots of the gold assembly generate local electromagnetic-field enhancement, favoring the four-photon upconversion process at the low-power excitation of approximately 13 W·cm-2 ...
November 28, 2018: Analytical Chemistry
Zhenglin Yang, Kang Yong Loh, Yueh-Te Chu, Ruopei Feng, Nitya Sai Reddy Satyavolu, Mengyi Xiong, Stephanie M Nakamata Huynh, Kevin Hwang, Lele Li, Hang Xing, XiaoBing Zhang, Yann R Chemla, Martin Gruebele, Yi Lu
Spatial and temporal distributions of metal ions in vitro and in vivo are crucial in our understanding of the roles of metal ions in biological systems, and yet there is a very limited number of methods to probe metal ions with high space and time resolution, especially in vivo. To overcome this limitation, we report a Zn2+-specific near infrared (NIR) DNAzyme nanoprobe for real-time metal ion tracking with spatiotemporal control in early embryos and larvae of zebrafish. By conjugating photocaged DNAzymes onto lanthanide-doped upconversion nanoparticles (UCNPs), we have achieved upconversion of a deep tissue penetrating NIR 980 nm light into 365 nm emission...
November 14, 2018: Journal of the American Chemical Society
Keying Zhang, Shuting Song, Lin Yang, Qianhao Min, Xingcai Wu, Jun-Jie Zhu
A microRNA (miRNA) fluorescence (FL) nanoprobe based on PDA-UCNPs@FAM-LLD@AuNPs was developed, which exhibited an enhanced signal for imaging intracellular miRNA by combining double-channel exciting single colour FL (DCESCF) with the target cycling amplification reaction. Through this strategy, normal cells and cancer cells could be successfully discriminated.
November 20, 2018: Chemical Communications: Chem Comm
Qiaofeng Li, Jialei Bai, Shuyue Ren, Jiang Wang, Yifei Gao, Shuang Li, Yuan Peng, Baoan Ning, Zhixian Gao
Bisphenol A (BPA) is one of the endocrine-disrupting chemicals which might cause reproductive and endocrine system diseases, and poses a serious threat to the ecosystem and human health. This paper reports an ultrasensitive sensor for trace BPA detection employing fluorescence resonance energy transfer (FRET) between modified upconversion nanoparticles (UCNPs) and tetramethylrhodamine. To circumvent the problems of low luminous efficiency of FRET and low sensitivity of sensor, the upconversion nanoparticles with very strong fluorescence efficiency were prepared and quantitatively modified...
November 3, 2018: Analytical and Bioanalytical Chemistry
Xiang Li, Hui Zhao, Yu Ji, Chao Yin, Jie Li, Zhen Yang, Yufu Tang, Qichun Zhang, Quli Fan, Wei Huang
Hydrogen sulfide (H2 S) is a versatile modulator in mitochondria and involved in numerous diseases caused by mitochondrial dysfunction. Therefore, many efforts have been made to develop fluorescent probes for mitochondrial H2 S detection. However, these cationic small molecule probes are inapplicable for in vivo imaging because of the shallow tissue penetration and poor biostability. Herein, a ratiometric upconversion luminescence nanoprobe with an acid-activated targeting strategy is developed for detecting and bioimaging of mitochondrial H2 S...
November 21, 2018: ACS Applied Materials & Interfaces
Xu Wang, Jie Yang, Xiujuan Sun, Hongliang Yu, Fei Yan, Kamel Meguellati, Ziyong Cheng, Haiyuan Zhang, Ying-Wei Yang
Upon surface functionalization and stabilization of β-NaYF4:Yb/Er upconversion nanoparticles (UCNPs) with phosphoryl pillar[5]arenes (PP5) via a facile ligand exchange method, we constructed a new hybrid material (PP5-UCNPs) with good water dispersibility especially in a physiological environment and superior capability of controlled cargo release and cell imaging.
November 15, 2018: Chemical Communications: Chem Comm
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