Artículos de revistas: "Nanoparticles, Upconversion, Nanothermometry, Lanthanides"

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Vetrone, Fiorenzo. "(Invited) Multi-Architectured Lanthanide Doped Nanoparticles for Theranostics". ECS Meeting Abstracts MA2022-01, n.º 53 (7 de julio de 2022): 2210. http://dx.doi.org/10.1149/ma2022-01532210mtgabs.

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Light triggered theranostic (therapy and diagnostic) nanoplatforms have gained a considerable attention in recent years. In theranostics, light as an external trigger stands out due to its non-invasiveness, high local precision and temporal resolution. Many such nanoplatforms employ high-energy (visible or UV) light to initiate the individual therapeutic and diagnostic modalities. However, light at these wavelengths suffers from inherent drawbacks such as having little to no penetration in living tissue, inducing autofluorescence from inherent fluorophores or chromophores in tissues and causing photodamage. The use of near-infrared (NIR) light for excitation mitigates such drawbacks associated with high-energy excitation, for example, little to no background autofluorescence from the specimen under investigation as well as no incurred photodamage. Moreover, one of the biggest limitations is that of penetration and NIR light can penetrate tissues much better than high-energy light especially when these wavelengths lie within the three biological windows where tissues are optically transparent. At the forefront of NIR excited nanomaterials are lanthanide doped nanoparticles, which can undergo conventional (Stokes) luminescence and emit in the NIR biological windows. However, unlike other classes of nanoparticles, they can also undergo a multiphoton excitation process where the NIR excitation light is converted to higher energies resulting in anti-Stokes luminescence spanning the UV-visible-NIR regions (known as upconversion). Thus, it now becomes possible to generate upconverted high-energy light (UV or visible) in situ to trigger other light activated therapeutic modalities (i.e. drug release) while using the NIR emission for diagnostics (i.e. bioimaging, nanothermometry). Here, we demonstrate how the luminescence properties (upconversion and NIR) of various lanthanide doped core/shell (and multishell) nanoparticles can be exploited for potential use in theranostics.

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Zheng, Shuhong, Weibo Chen, Dezhi Tan, Jiajia Zhou, Qiangbing Guo, Wei Jiang, Cheng Xu, Xiaofeng Liu y Jianrong Qiu. "Lanthanide-doped NaGdF4 core–shell nanoparticles for non-contact self-referencing temperature sensors". Nanoscale 6, n.º 11 (2014): 5675–79. http://dx.doi.org/10.1039/c4nr00432a.

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Li, Hao, Esmaeil Heydari, Yinyan Li, Hui Xu, Shiqing Xu, Liang Chen y Gongxun Bai. "Multi-Mode Lanthanide-Doped Ratiometric Luminescent Nanothermometer for Near-Infrared Imaging within Biological Windows". Nanomaterials 13, n.º 1 (3 de enero de 2023): 219. http://dx.doi.org/10.3390/nano13010219.

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Owing to its high reliability and accuracy, the ratiometric luminescent thermometer can provide non-contact and fast temperature measurements. In particular, the nanomaterials doped with lanthanide ions can achieve multi-mode luminescence and temperature measurement by modifying the type of doped ions and excitation light source. The better penetration of the near-infrared (NIR) photons can assist bio-imaging and replace thermal vision cameras for photothermal imaging. In this work, we prepared core–shell cubic phase nanomaterials doped with lanthanide ions, with Ba2LuF7 doped with Er3+/Yb3+/Nd3+ as the core and Ba2LaF7 as the coating shell. The nanoparticles were designed according to the passivation layer to reduce the surface energy loss and enhance the emission intensity. Green upconversion luminescence can be observed under both 980 nm and 808 nm excitation. A single and strong emission band can be obtained under 980 nm excitation, while abundant and weak emission bands appear under 808 nm excitation. Meanwhile, multi-mode ratiometric optical thermometers were achieved by selecting different emission peaks in the NIR window under 808 nm excitation for non-contact temperature measurement at different tissue depths. The results suggest that our core–shell NIR nanoparticles can be used to assist bio-imaging and record temperature for biomedicine.

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Liu, Huiming, Long Yan, Jinshu Huang, Zhengce An, Wang Sheng y Bo Zhou. "Ultrasensitive Thermochromic Upconversion in Core–Shell–Shell Nanoparticles for Nanothermometry and Anticounterfeiting". Journal of Physical Chemistry Letters 13, n.º 10 (4 de marzo de 2022): 2306–12. http://dx.doi.org/10.1021/acs.jpclett.2c00005.

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5

Lin, Mei, Liujing Xie, Zijun Wang, Bryce S. Richards, Guojun Gao y Jiuping Zhong. "Facile synthesis of mono-disperse sub-20 nm NaY(WO4)2:Er3+,Yb3+ upconversion nanoparticles: a new choice for nanothermometry". Journal of Materials Chemistry C 7, n.º 10 (2019): 2971–77. http://dx.doi.org/10.1039/c8tc05669b.

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6

Halubek-Gluchowska, Katarzyna, Damian Szymański, Thi Ngoc Lam Tran, Maurizio Ferrari y Anna Lukowiak. "Upconversion Luminescence of Silica–Calcia Nanoparticles Co-doped with Tm3+ and Yb3+ Ions". Materials 14, n.º 4 (16 de febrero de 2021): 937. http://dx.doi.org/10.3390/ma14040937.

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Looking for upconverting biocompatible nanoparticles, we have prepared by the sol–gel method, silica–calcia glass nanopowders doped with different concentration of Tm3+ and Yb3+ ions (Tm3+ from 0.15 mol% up to 0.5 mol% and Yb3+ from 1 mol% up to 4 mol%) and characterized their structure, morphology, and optical properties. X-ray diffraction patterns indicated an amorphous phase of the silica-based glass with partial crystallization of samples with a higher content of lanthanides ions. Transmission electron microscopy images showed that the average size of particles decreased with increasing lanthanides content. The upconversion (UC) emission spectra and fluorescence lifetimes were registered under near infrared excitation (980 nm) at room temperature to study the energy transfer between Yb3+ and Tm3+ at various active ions concentrations. Characteristic emission bands of Tm3+ ions in the range of 350 nm to 850 nm were observed. To understand the mechanism of Yb3+–Tm3+ UC energy transfer in the SiO2–CaO powders, the kinetics of luminescence decays were studied.

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7

Xu, Hanyu, Mochen Jia, Zhiying Wang, Yanling Wei y Zuoling Fu. "Enhancing the Upconversion Luminescence and Sensitivity of Nanothermometry through Advanced Design of Dumbbell-Shaped Structured Nanoparticles". ACS Applied Materials & Interfaces 13, n.º 51 (15 de diciembre de 2021): 61506–17. http://dx.doi.org/10.1021/acsami.1c17900.

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8

Ferrera-González, Juan, Laura Francés-Soriano, Cristina Galiana-Roselló, Jorge González-Garcia, María González-Béjar, Eleonore Fröhlich y Julia Pérez-Prieto. "Initial Biological Assessment of Upconversion Nanohybrids". Biomedicines 9, n.º 10 (9 de octubre de 2021): 1419. http://dx.doi.org/10.3390/biomedicines9101419.

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Nanoparticles for medical use should be non-cytotoxic and free of bacterial contamination. Upconversion nanoparticles (UCNPs) coated with cucurbit[7]uril (CB[7]) made by combining UCNPs free of oleic acid, here termed bare UCNPs (UCn), and CB[7], i.e., UC@CB[7] nanohybrids, could be used as photoactive inorganic-organic hybrid scaffolds for biological applications. UCNPs, in general, are not considered to be highly toxic materials, but the release of fluorides and lanthanides upon their dissolution may cause cytotoxicity. To identify potential adverse effects of the nanoparticles, dehydrogenase activity of endothelial cells, exposed to various concentrations of the UCNPs, was determined. Data were verified by measuring lactate dehydrogenase release as the indicator of loss of plasma membrane integrity, which indicates necrotic cell death. This assay, in combination with calcein AM/Ethidium homodimer-1 staining, identified induction of apoptosis as main mode of cell death for both particles. The data showed that the UCNPs are not cytotoxic to endothelial cells, and the samples did not contain endotoxin contamination. Higher cytotoxicity, however, was seen in HeLa and RAW 264.7 cells. This may be explained by differences in lysosome content and particle uptake rate. Internalization of UCn and UC@CB[7] nanohybrids by cells was demonstrated by NIR laser scanning microscopy.

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9

Yang, Han Yu. "Lanthanide-Based Nanoprobes for Time-Resolved Luminescence Imaging on Various Ions and Molecules". Materials Science Forum 1075 (30 de noviembre de 2022): 9–17. http://dx.doi.org/10.4028/p-76fds1.

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Lanthanide-doped upconversion nanoparticles (Ln-UCNPs) have been extensively explored in the biological field. In particular, Ln-UCNPs with near-infrared (NIR) fluorescence have tremendous potential for biological imaging because of their outstanding photo-and chemo-stability, extended photoluminescence lifetimes, low long-term toxicities and narrow photoluminescence bandwidths as well as minimal background interferences. Using predesigned energy transfer routes makes it possible to get upconversion luminescence from lanthanides' 4f-4f optical transitions. This article clarifies the key working principles and superiorities of Ln-UCNPs for bioimaging. A crucial overview of recent advances in biological detection adopting lanthanide-based luminescence resonance energy transfer (LRET) mechanisms is presented while emphasizing the importance of modifying Ln-UCNPs to obtain a more efficient energy transfer mechanism.

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10

Rostami, Iman. "Empowering the Emission of Upconversion Nanoparticles for Precise Subcellular Imaging". Nanomaterials 11, n.º 6 (11 de junio de 2021): 1541. http://dx.doi.org/10.3390/nano11061541.

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Upconversion nanoparticles (UCNPs) are a class of inorganic fluorophores that follow the anti-Stokes mechanism, to which the wavelength of emission is shorter than absorption. This unique optical behavior generates relatively long-lived intermediate energy levels of lanthanides that stabilize the excitation state in the fluorescence process. Longer-wavelength light sources, e.g., near-infrared (NIR), penetrate deeper into biological materials such as tissue and cells that provide a larger working space for cell biology applications and imaging, whereby UCNPs have recently gained increasing interest in medicine. In this report, the emission intensity of a gadolinium-based UCNP was screened by changing the concentrations of the constituents. The optimized condition was utilized as a luminescent nanoprobe for targeting the mitochondria as a distinguished subcellular organelle within differentiated neuroblastoma cells. The main goal of this study is to illustrate the targeting process within the cells in a native state using modified UCNPs. Confocal microscopy on the cells treated with the functionalized UCNPs indicated a selective accumulation of UCNPs after immunolabeling. To tackle the insolubility of as-synthesized particles in water-based media, the optimized UCNPs were surface-coated with polyamidoamine (PAMAM) dendrimers that due to peripheral amino groups are suitable for functionalizing with peptides and antibodies. Ultimately, we concluded that UCNPs are potentially versatile and ideal tools for NIR bioimaging and capable of making adequate contrast against biomaterials to be detectable in electron microscopy (EM) imaging.

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11

Hemmer, Eva. "(Invited) Rare-Earth-Based Nanoparticles As Multimodal Bioprobes". ECS Meeting Abstracts MA2022-01, n.º 53 (7 de julio de 2022): 2212. http://dx.doi.org/10.1149/ma2022-01532212mtgabs.

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The remarkable optomagnetic properties of the rare-earths (RE) make RE-based materials ideal for biomedical applications, including diagnostic (e.g., imaging, nanothermometry) and therapeutic (e.g., drug delivery, photodynamic therapy) approaches. This is due the unique electronic properties of the f-elements allowing for upconversion and near-infrared emission under near-infrared excitation as well as high magnetic moments. Yet, challenges remain; low emission intensity and efficiency of small nanoparticles (NPs), and reliable, fast synthesis routes. As material chemists, we tackle these challenges with new designs of RE-NPs by chemically controlled synthesis, application-oriented surface chemistry, and understanding of structure-property-relationships. Sodium rare-earth fluorides (NaREF4) are our favorite materials, and we developed a fast and reliable microwave-assisted synthesis approach allowing crystalline phase and size control in the sub 15nm realm. Such control is crucial for the understanding of fundamental structure-property relationships and to optimize their optical and magnetic properties, when aiming for the design of next-generation optical probes or contrast agents for magnetic resonance imaging. For instance, NaGdF4 NPs are gaining interest as alternative MRI contrast agent, while co-doping with RE3+ ions renders them excellent candidates for photoluminescent optical probes. The hexagonal crystalline phase of NaGdF4 is known as the more efficient host material for upconversion emission, yet interestingly, it was found that its cubic counterpart shows superior performance as MRI contrast agent. Having a fast and reliable synthesis route towards NaREF4 NPs on hand, we now explore various nanoparticle architectures and compositions with the goal to optimize their optomagnetic properties, ultimately resulting in the design of biocompatible multimodal bioprobes. This presentation will shed light on recent results and remaining challenges in the field of RE-based nanostructures with respect to their microwave-assisted synthesis as well as structural and optomagnetic properties, seeking biomedical application, while also touching on hyperspectral imaging as an emerging analytical tool offering spatio-spectral information about RE-based materials.

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12

Sun, Lining. "(Digital Presentation) Tailored Rare Earth-Doped Nanomaterials Toward Information Storage and Deep Learning Decoding". ECS Meeting Abstracts MA2022-02, n.º 51 (9 de octubre de 2022): 1981. http://dx.doi.org/10.1149/ma2022-02511981mtgabs.

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Lanthanide-doped nanoparticles have been considered as one of the most promising luminescent materials due to their excellent properties such as high photochemical stability, long-lived (μs-ms) luminescence, narrow emission band, and low toxicity.Moreover, benefiting from a unique electronic structure (4fn5s25p6 , n = 0-14), lanthanides have discrete energy levels and exhibit practical wavelength conversion via downshifting and upconversion processes. Hence, their emissions cover the spectral regions from ultraviolet (UV) to near-infrared (NIR).[1,2] Here, my talk is mainly devoted to our recent developments, including (1) recently, we present a new composition of Er3+-based upconversion nanoparticles with color-switchable output under irradiation with 980, 808, or 1535 nm light for information security. The variation of excitation wavelengths changes the intensity ratio of visible (Vis)/near-infrared 1535 nm (NIR-II) emissions. Taking advantage of the Vis/NIR-II multi-modal emissions of upconversion nanoparticles and deep learning, we successfully demonstrated the storage and decoding of visible light information in pork tissue.[3] (2) we construct heterostructured nanocomposites based on upconversion nanoparticles and EuSe semiconductors by using cation exchange method. It is generally considered that epitaxial growth is difficult when the lattice mismatch is large between two materials. In this case, the cation exchange of Eu3+ ions and other rare-earth ions could promote the formation of buffer layers to reduce the lattice mismatch and promote the heterogeneous epitaxial growth of EuSe on the upconversion nanoparticles. The heterostructured nanocomposites can emit tunable multicolor fluorescence under excitation of UV, continuous NIR, and pulsed NIR light. Based on the advantage of multiple tunable luminescence, the nanocomposites are designed as optical modules to load optical information. This work enables multi-dimensional storage of information and provides new insights into the design and fabrication of next-generation storage materials. References [1] L. N. Sun, R. Wei, J. Feng, and H. J. Zhang, Tailored lanthanide-doped upconversion nanoparticles and their promising bioapplication prospects, Coordination Chemistry Reviews, 2018, 364, 10-32. [2] G. Sun, Y. Xie, L. N. Sun, and H. J. Zhang, Lanthanide Upconversion and Downshifting Luminescence for Biomolecules Detection, Nanoscale Horizons, 2021, 6(10), 766 – 780. [3] Y. Song, M. Lu, G. A. Mandl, Y. Xie, G. Sun,J. Chen, X. Liu,J. A. Capobianco, and L. N. Sun, “Energy Migration Control of Multimodal Emissions in an Er3+-Doped Nanostructure for Information Encryption and Deep-Learning Decoding”, Angewandte Chemie International Edition , 2021, 60(44), 23790–23796.

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13

Savchuk, Oleksandr, Joan Josep Carvajal Marti, Concepción Cascales, Patricia Haro-Gonzalez, Francisco Sanz-Rodríguez, Magdalena Aguilo y Francesc Diaz. "Bifunctional Tm3+,Yb3+:GdVO4@SiO2 Core-Shell Nanoparticles in HeLa Cells: Upconversion Luminescence Nanothermometry in the First Biological Window and Biolabelling in the Visible". Nanomaterials 10, n.º 5 (21 de mayo de 2020): 993. http://dx.doi.org/10.3390/nano10050993.

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The bifunctional possibilities of Tm,Yb:GdVO4@SiO2 core-shell nanoparticles for temperature sensing by using the near-infrared (NIR)-excited upconversion emissions in the first biological window, and biolabeling through the visible emissions they generate, were investigated. The two emission lines located at 700 and 800 nm, that arise from the thermally coupled 3F2,3 and 3H4 energy levels of Tm3+, were used to develop a luminescent thermometer, operating through the Fluorescence Intensity Ratio (FIR) technique, with a very high thermal relative sensitivity. Moreover, since the inert shell surrounding the luminescent active core allows for dispersal of the nanoparticles in water and biological compatible fluids, we investigated the penetration depth that can be realized in biological tissues with their emissions in the NIR range, achieving a value of 0.8 mm when excited at powers of 50 mW. After their internalization in HeLa cells, a low toxicity was observed and the potentiality for biolabelling in the visible range was demonstrated, which facilitated the identification of the location of the nanoparticles inside the cells, and the temperature determination.

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14

Vetrone, Fiorenzo. "(Invited) Rare Earth Doped Nanoparticles". ECS Meeting Abstracts MA2022-02, n.º 36 (9 de octubre de 2022): 1319. http://dx.doi.org/10.1149/ma2022-02361319mtgabs.

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Luminescent nanomaterials that can be excited, as well as emit, in the near-infrared (NIR) have been investigated for use in a plethora of applications including nanomedicine, nanoelectronics, biosensing, bioimaging, photovoltaics, photocatalysis, etc. The use of NIR light for excitation mitigates some of the drawbacks associated with high-energy (UV or blue) excitation, for example, little to no background autofluorescence from the specimen under investigation as well as no incurred photodamage. Moreover, one of the biggest limitations is of course, that of penetration. As such, NIR light can penetrate tissues much better than high-energy light especially when these wavelengths lie within the three biological windows (BW-I: 700-950, BW-II: 1000-1350, BW-III: 1550-1870 nm) where tissues are optically transparent. At the forefront of NIR excited nanomaterials are rare earth doped nanoparticles, which due to their 4f electronic energy states can undergo conventional (Stokes) luminescence and emit in the three NIR biological windows. However, unlike other classes of nanoparticles, they can also undergo a multiphoton process (known as upconversion) where the NIR excitation light is converted to higher energies resulting in anti-Stokes luminescence spanning the UV-visible-NIR regions. Perhaps the biggest impact of such materials would be in the field of disease diagnostics and therapeutics, now commonly referred to as theranostics. Due to the versatility of their optical properties, it now becomes possible to generate high-energy light (UV or blue) in situ to trigger other light activated therapeutic modalities (i.e. drug release) while using the NIR emission for diagnostics (i.e. bioimaging, nanothermometry). Here, we present the synthesis of various NIR excited (and emitting) rare earth doped core/shell (and multishell) nanoparticles and demonstrate how their luminescence properties can be exploited for potential use in diverse biomedical applications.

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15

Kamimura, Masao, Yuto Yano, Shuhei Kuraoka, Satoru Suyari, Takuji Ube, Laura Wortmann y Kohei Soga. "Near-Infrared to Visible Upconversion Emission Induced Photopolymerization: Polystyrene Shell Coated NaYF₄ Nanoparticles for Fluorescence Bioimaging and Nanothermometry". Journal of Photopolymer Science and Technology 30, n.º 3 (2017): 265–70. http://dx.doi.org/10.2494/photopolymer.30.265.

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16

Senthilselvan, J., Sinju Thomas, L. Anbharasi, Debashrita Sarkar, Venkata N. K. B. Adusumalli, S. Arun Kumar, S. Yamini, M. Gunaseelan, J. Manonmani y Venkataramanan Mahalingam. "EDTA functionalization of SrF2:Yb,Er nanoparticles by hydrothermal synthesis: Intense red upconversion, NIR-to-NIR emission and luminescence nanothermometry characteristics". Journal of Materials Science: Materials in Electronics 30, n.º 23 (30 de octubre de 2019): 20376–92. http://dx.doi.org/10.1007/s10854-019-02311-y.

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17

Dos Santos, L. F., J. C. Martins, K. O. Lima, L. F. T. Gomes, M. T. De Melo, A. C. Tedesco, L. D. Carlos, R. A. S. Ferreira y R. R. Gonçalves. "In vitro assays and nanothermometry studies of infrared-to-visible upconversion of nanocrystalline Er3+,Yb3+ co-doped Y2O3 nanoparticles for theranostic applications". Physica B: Condensed Matter 624 (enero de 2022): 413447. http://dx.doi.org/10.1016/j.physb.2021.413447.

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18

Nahorniak, Mykhailo, Ognen Pop-Georgievski, Nadiia Velychkivska, Marcela Filipová, Eliška Rydvalová, Kristýna Gunár, Petr Matouš, Uliana Kostiv y Daniel Horák. "Rose Bengal-Modified Upconverting Nanoparticles: Synthesis, Characterization, and Biological Evaluation". Life 12, n.º 9 (5 de septiembre de 2022): 1383. http://dx.doi.org/10.3390/life12091383.

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High-quality upconverting NaYF4:Yb3+,Er3+ nanoparticles (UCNPs; 26 nm in diameter) based on lanthanides were synthesized by a high-temperature coprecipitation method. The particles were modified by bisphosphonate-terminated poly(ethylene glycol) (PEG) and Rose Bengal (RB) photosensitizer. The particles were thoroughly characterized using transmission electron microscopy, dynamic light scattering, thermogravimetric analysis, FTIR, and X-ray photoelectron and upconversion luminescence spectroscopy in terms of morphology, hydrodynamic size, composition, and energy transfer to the photosensitizer. Moreover, the singlet oxygen generation from RB-containing UCNPs was investigated using 9,10-diphenylanthracene probe under 980 nm excitation. The cytotoxicity of UCNPs before and after conjugation with RB was evaluated on highly sensitive rat mesenchymal stem cells (rMSCs) and significant differences were found. Correspondingly, consi-derable variations in viability were revealed between the irradiated and non-irradiated rat glioma cell line (C6) exposed to RB-conjugated UCNPs. While the viability of rMSCs was not affected by the presence of UCNPs themselves, the cancer C6 cells were killed after the irradiation at 980 nm due to the reactive oxygen species (ROS) production, thus suggesting the potential of RB-conjugated PEG-modified UCNPs for applications in photodynamic therapy of cancer.

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de Oliveira Lima, Karmel, Luiz Fernando dos Santos, Rodrigo Galvão, Antonio Claudio Tedesco, Leonardo de Souza Menezes y Rogéria Rocha Gonçalves. "Single Er3+, Yb3+: KGd3F10 Nanoparticles for Nanothermometry". Frontiers in Chemistry 9 (21 de julio de 2021). http://dx.doi.org/10.3389/fchem.2021.712659.

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Among several optical non-contact thermometry methods, luminescence thermometry is the most versatile approach. Lanthanide-based luminescence nanothermometers may exploit not only downshifting, but also upconversion (UC) mechanisms. UC-based nanothermometers are interesting for biological applications: they efficiently convert near-infrared radiation to visible light, allowing local temperatures to be determined through spectroscopic investigation. Here, we have synthesized highly crystalline Er3+, Yb3+ co-doped upconverting KGd3F10 nanoparticles (NPs) by the EDTA-assisted hydrothermal method. We characterized the structure and morphology of the obtained NPs by transmission electron microscopy, X-ray diffraction, Raman spectroscopy, and dynamic light scattering. Nonlinear spectroscopic studies with the Er3+, Yb3+: KGd3F10 powder showed intense green and red emissions under excitation at 980 and 1,550 nm. Two- and three-photon processes were attributed to the UC mechanisms under excitation at 980 and 1,550 nm. Strong NIR emission centered at 1,530 nm occurred under low 980-nm power densities. Single NPs presented strong green and red emissions under continuous wave excitation at 975.5 nm, so we evaluated their use as primary nanothermometers by employing the Luminescence Intensity Ratio technique. We determined the temperature felt by the dried NPs by integrating the intensity ratio between the thermally coupled 2H11/2→4I15/2 and 4S3/2→4I15/2 levels of Er3+ ions in the colloidal phase and at the single NP level. The best thermal sensitivity of a single Er3+, Yb3+: KGd3F10 NP was 1.17% at the single NP level for the dry state at 300 K, indicating potential application of this material as accurate nanothermometer in the thermal range of biological interest. To the best of our knowledge, this is the first promising thermometry based on single KGd3F10 particles, with potential use as biomarkers in the NIR-II region.

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Di, Xiangjun, Dejiang Wang, Qian Peter Su, Yongtao Liu, Jiayan Liao, Mahnaz Maddahfar, Jiajia Zhou y Dayong Jin. "Spatiotemporally mapping temperature dynamics of lysosomes and mitochondria using cascade organelle-targeting upconversion nanoparticles". Proceedings of the National Academy of Sciences 119, n.º 45 (2 de noviembre de 2022). http://dx.doi.org/10.1073/pnas.2207402119.

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The intracellular metabolism of organelles, like lysosomes and mitochondria, is highly coordinated spatiotemporally and functionally. The activities of lysosomal enzymes significantly rely on the cytoplasmic temperature, and heat is constantly released by mitochondria as the byproduct of adenosine triphosphate (ATP) generation during active metabolism. Here, we developed temperature-sensitive LysoDots and MitoDots to monitor the in situ thermal dynamics of lysosomes and mitochondria. The design is based on upconversion nanoparticles (UCNPs) with high-density surface modifications to achieve the exceptionally high sensitivity of 2.7% K −1 and low uncertainty of 0.8 K for nanothermometry to be used in living cells. We show the measurement is independent of the ion concentrations and pH values. With Ca 2+ ion shock, the temperatures of both lysosomes and mitochondria increased by ∼2 to 4 °C. Intriguingly, with chloroquine (CQ) treatment, the lysosomal temperature was observed to decrease by up to ∼3 °C, while mitochondria remained relatively stable. Lastly, with oxidative phosphorylation inhibitor treatment, we observed an ∼3 to 7 °C temperature increase and a thermal transition from mitochondria to lysosomes. These observations indicate different metabolic pathways and thermal transitions between lysosomes and mitochondria inside HeLa cells. The nanothermometry probes provide a powerful tool for multimodality functional imaging of subcellular organelles and interactions with high spatial, temporal, and thermal dynamics resolutions.

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Qiu, Xiaochen, Qianwen Zhou, Xingjun Zhu, Zugen Wu, Wei Feng y Fuyou Li. "Ratiometric upconversion nanothermometry with dual emission at the same wavelength decoded via a time-resolved technique". Nature Communications 11, n.º 1 (7 de enero de 2020). http://dx.doi.org/10.1038/s41467-019-13796-w.

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AbstractThe in vivo temperature monitoring of a microenvironment is significant in biology and nanomedicine research. Luminescent nanothermometry provides a noninvasive method of detecting the temperature in vivo with high sensitivity and high response speed. However, absorption and scattering in complex tissues limit the signal penetration depth and cause errors due to variation at different locations in vivo. In order to minimize these errors and monitor temperature in vivo, in the present work, we provided a strategy to fabricate a same-wavelength dual emission ratiometric upconversion luminescence nanothermometer based on a hybrid structure composed of upconversion emissive PbS quantum dots and Tm-doped upconversion nanoparticles. The ratiometric signal composed of two upconversion emissions working at the same wavelength, but different luminescent lifetimes, were decoded via a time-resolved technique. This nanothermometer improved the temperature monitoring ability and a thermal resolution and sensitivity of ~0.5 K and ~5.6% K−1 were obtained in vivo, respectively.

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Artículos de revistas sobre el tema "Nanoparticles, Upconversion, Nanothermometry, Lanthanides"

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