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Статті в журналах з теми "Fluorescence Gold Clusters"

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Автор: Grafiati

Опубліковано: 7 вересня 2023

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1

Raj, D. Rithesh, and C. Sudarsanakumar. "Surface Plasmon Resonance Based Fiber Optic Dopamine Sensor Using BSA-Gold Cluster/Polymer Composites." Advanced Science Letters 24, no. 8 (August 1, 2018): 5598–602. http://dx.doi.org/10.1166/asl.2018.12157.

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Highly luminescent BSA-gold clusters were synthesized and its polymer composites were prepared using PVA, PVP and PVA/PVP blend. UV-visible spectroscopy, Photoluminescence, Fourier transform infrared spectroscopy (FTIR), Transmission electron microscopy (TEM) and particle size analysis (DLS) were performed to determine the formation of gold clusters. Luminescence properties of BSA-Gold cluster and its polymer composites were evaluated and it is found that all polymers quench the fluorescence at 650 nm while PVP and PVP/PVA blend enhance the fluorescence at 450 nm. Further, a Surface Plasmon Resonance (SPR) based fiber optic sensor has been fabricated using PVP/BSA-gold clusters as the sensing material and its dopamine sensing properties were studied. The sensor shows a linear response in the range of 0 to 80 μM concentrations of dopamine and the limit of detection (LOD) of the sensor is 12 μM.

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2

Carotenuto, G., S. De Nicola, and L. Nicolais. "Fluorescent Thiol-Derivatized Gold Clusters Embedded in Polymers." Advances in Materials Science and Engineering 2013 (2013): 1–6. http://dx.doi.org/10.1155/2013/548284.

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Owing to aurophilic interactions, linear and/or planar Au(I)-thiolate molecules spontaneously aggregate, leading to molecular gold clusters passivated by a thiolate monolayer coating. Differently from the thiolate precursors, such cluster compounds show very intensive visible fluorescence characteristics that can be tuned by alloying the gold clusters with silver atoms or by conjugating the electronic structure of the metallic core with unsaturated electronic structures in the organic ligand through the sulphur atom. Here, the photoluminescence features of some examples of these systems are shortly described.

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3

CAROTENUTO, G., A. LONGO, L. DE PETROCELLIS, S. DE NICOLA, P. REPETTO, P. PERLO, and L. AMBROSIO. "SYNTHESIS OF MOLECULAR GOLD CLUSTERS WITH LUMINESCENCE PROPERTIES BY MERCAPTIDE THERMOLYSIS IN POLYMER MATRICES." International Journal of Nanoscience 06, no. 01 (February 2007): 65–69. http://dx.doi.org/10.1142/s0219581x07004225.

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Highly fluorescent Au /polystyrene nanocomposite films have been prepared by thermal decomposition at 250°C of gold mercaptide molecules (dodecyl-mercaptide of gold(I), C 12 H 25 SAu ) dissolved in polystyrene. Owing to a continuous nucleation of metallic phase generated by the thermolysis reaction, molecular gold clusters, which are characterized by fluorescence properties because of the very small size, can be obtained by this very simple technique.

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4

Ganguly, Mainak, Jayasmita Jana, Anjali Pal, and Tarasankar Pal. "Synergism of gold and silver invites enhanced fluorescence for practical applications." RSC Advances 6, no. 21 (2016): 17683–703. http://dx.doi.org/10.1039/c5ra26430h.

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5

Qu, Xiaochao, Yichen Li, Lei Li, Yanran Wang, Jingning Liang, and Jimin Liang. "Fluorescent Gold Nanoclusters: Synthesis and Recent Biological Application." Journal of Nanomaterials 2015 (2015): 1–23. http://dx.doi.org/10.1155/2015/784097.

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Fluorescent gold nanoclusters (AuNCs) have been extensively studied due to their unique construction and distinctive properties, which place them between single metal atoms and larger nanoparticles. The dimension of AuNCs is comparable to the Fermi wavelength of electrons, which lead to size-dependent fluorescence and other molecule-like properties. In this review, we summarize various synthesis strategies of fluorescent AuNCs and recent advances of biological applications such as biosensing, biolabeling, and bioimaging. The synthetic methods are considered as two routes: “Atoms to Clusters” and “Nanoparticles to Clusters.” The surface functionalization of AuNCs is described as the precondition for making future bioapplications possible, which can eventually influence their stability, biocompatibility, and other properties. And then we focus on the recent advances of AuNCs-based applications in biological sensing, biolabeling, and bioimaging and finally discuss the current challenges of AuNCs in controllable synthesis and biological application.

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6

Zhang, Yuwei, Ping Song, Tiankai Chen, Xiaodong Liu, Tao Chen, Zhemin Wu, Yong Wang, Jianping Xie, and Weilin Xu. "Unique size-dependent nanocatalysis revealed at the single atomically precise gold cluster level." Proceedings of the National Academy of Sciences 115, no. 42 (October 1, 2018): 10588–93. http://dx.doi.org/10.1073/pnas.1805711115.

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Atomically precise metal clusters have attracted increasing interest owing to their unique size-dependent properties; however, little has been known about the effect of size on the catalytic properties of metal clusters at the single-cluster level. Here, by real-time monitoring with single-molecule fluorescence microscopy the size-dependent catalytic process of individual Au clusters at single-turnover resolution, we study the size-dependent catalytic behaviors of gold (Au) clusters at the single-cluster level, and then observe the strong size effect on the catalytic properties of individual Au clusters, in both catalytic product formation and dissociation processes. Surprisingly, indicated by both experiments and density functional theory (DFT) calculations, due to such a unique size effect, besides observing the different product dissociation behaviors on different-sized Au clusters, we also observe that small Au clusters [i.e., Au15(MPA)13; here, MPA denotes 3-mercaptopropionic acid] catalyze the product formation through a competitive Langmuir–Hinshelwood mechanism, while those relatively larger Au clusters [e.g., Au18(MPA)14 and Au25(MPA)18] or nanoparticles catalyze the same process through a noncompetitive Langmuir–Hinshelwood mechanism. Such a size effect on the nanocatalysis could be attributed intrinsically to the size-dependent electronic structure of Au clusters. Further analysis of dynamic activity fluctuation of Au clusters reveals more different catalytic properties between Au clusters and traditional Au nanoparticles due to their different size-dependent structures.

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7

Dolai, Santanu, Srestha Basu, and Anumita Paul. "Aggregation induced delayed green fluorescence from assembly of gold nanoclusters: an advanced probe for “background free” pyrophosphate recognition." Materials Advances 3, no. 7 (2022): 3286–92. http://dx.doi.org/10.1039/d1ma01095f.

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8

Sugiuchi, Mizuho, Junichi Maeba, Nobuyuki Okubo, Munetaka Iwamura, Koichi Nozaki, and Katsuaki Konishi. "Aggregation-Induced Fluorescence-to-Phosphorescence Switching of Molecular Gold Clusters." Journal of the American Chemical Society 139, no. 49 (November 30, 2017): 17731–34. http://dx.doi.org/10.1021/jacs.7b10201.

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9

Battista, Edmondo, Maria Laura Coluccio, Alessandro Alabastri, Marianna Barberio, Filippo Causa, Paolo Antonio Netti, Enzo Di Fabrizio, and Francesco Gentile. "Metal enhanced fluorescence on super-hydrophobic clusters of gold nanoparticles." Microelectronic Engineering 175 (May 2017): 7–11. http://dx.doi.org/10.1016/j.mee.2016.12.013.

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10

Moreaud, Laureen, Janak Prasad, Serges Mazères, Cécile Marcelot, Clothilde Comby-Zerbino, Rodolphe Antoine, Olivier Heintz, and Erik Dujardin. "Facile one-pot synthesis of white emitting gold nanocluster solutions composed of red, green and blue emitters." Journal of Materials Chemistry C 10, no. 6 (2022): 2263–70. http://dx.doi.org/10.1039/d1tc04874k.

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11

Paccaud, J. P., J. L. Carpentier, and J. A. Schifferli. "Direct evidence for the clustered nature of complement receptors type 1 on the erythrocyte membrane." Journal of Immunology 141, no. 11 (December 1, 1988): 3889–94. http://dx.doi.org/10.4049/jimmunol.141.11.3889.

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Abstract C receptors 1 (CR1) of human E are involved in the transport of C3b-coated immune complexes (IC) in the circulation. Many studies have suggested that the binding of IC to E is multivalent. This would require CR1 to be clustered on the cell membrane, but no direct evidence for such clustering is available. We studied the distribution of CR1 on human E by immunofluorescence and shadow-casting immuno-electron microscopy techniques with the use of a monoclonal anti-CR1 antibody followed by FITC- or gold-conjugated second antibodies, respectively. By immunofluorescence, CR1 appeared as small dots (clusters) on fixed and unfixed E prepared either at 4 degrees C or at 37 degrees C. In the same donor, the number of clusters varied extensively from cell to cell (e.g., 1 to 43 clusters/E for a donor with 520 CR1/cell), but the mean number of clusters per cell correlated significantly with the mean number of CR1/cell. These images contrasted with those obtained for Rhesus D (RhD) Ag used as controls (RhD Ag are known to be evenly distributed): only a faint uniform fluorescence was seen despite the presence of 10,000 antigenic sites. As determined by immunocytochemical method, more than 65% of the total gold particles were organized in clusters (2 to 15 gold particles/cluster) whether cells were prefixed or not. Quantitative determinations suggested that each gold particle corresponded to one CR1. The fraction of gold particles grouped into clusters of three or more receptors, the mean size of the clusters, and the maximal size of clusters correlated with the mean number of CR1 per cell. By contrast, RhD Ag were distributed homogeneously (less than 2% gold particles in clusters). These data are the first to demonstrate the preclustered nature of CR1 on E. Such distribution could explain the high binding efficiency of C3b-coated IC to E despite the low number of CR1 per cell.

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12

Nair, Lakshmi V., Shaiju S. Nazeer, Ramapurath S. Jayasree, and Ayyappanpillai Ajayaghosh. "Fluorescence Imaging Assisted Photodynamic Therapy Using Photosensitizer-Linked Gold Quantum Clusters." ACS Nano 9, no. 6 (May 15, 2015): 5825–32. http://dx.doi.org/10.1021/acsnano.5b00406.

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13

Liu, Xianhu, Yishi Wu, Shuanghao Li, Yan Zhao, Chengqian Yuan, Meiye Jia, Zhixun Luo, Hongbing Fu, and Jiannian Yao. "Quantum-size-effect accommodation of gold clusters with altered fluorescence of dyes." RSC Advances 5, no. 39 (2015): 30610–16. http://dx.doi.org/10.1039/c4ra17239f.

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14

Gaio, Michele, Marta Castro-Lopez, Jan Renger, Niek van Hulst, and Riccardo Sapienza. "Percolating plasmonic networks for light emission control." Faraday Discussions 178 (2015): 237–52. http://dx.doi.org/10.1039/c4fd00187g.

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Optical nanoantennas have revolutionised the way we manipulate single photons emitted by individual light sources in a nanostructured photonic environment. Complex plasmonic architectures allow for multiscale light control by shortening or stretching the light wavelength for a fixed operating frequency, meeting the size of the emitter and that of propagating modes. Here, we study self-assembled semi-continuous gold films and lithographic gold networks characterised by large local density of optical state (LDOS) fluctuations around the electrical percolation threshold, a regime where the surface is characterised by large metal clusters with fractal topology. We study the formation of plasmonic networks and their effect on light emission from embedded fluorescent probes in these systems. Through fluorescence dynamics experiments we discuss the role of global long-range interactions linked to the degree of percolation and to the network fractality, as well as the local near-field contributions coming from the local electro-magnetic fields and the topology. Our experiments indicate that local properties dominate the fluorescence modification.

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15

Yang, Yayu, Ailing Han, Ruixue Li, Guozhen Fang, Jifeng Liu, and Shuo Wang. "Synthesis of highly fluorescent gold nanoclusters and their use in sensitive analysis of metal ions." Analyst 142, no. 23 (2017): 4486–93. http://dx.doi.org/10.1039/c7an01348e.

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16

Li, Yan, Aowei Zhao, Jieqiong Wang, Jieyu Yu, Fei Xiao, and Hongcheng Sun. "Highly Bright Gold Nanowires Arrays for Sensitive Detection of Urea and Urease." Nanomaterials 12, no. 22 (November 16, 2022): 4023. http://dx.doi.org/10.3390/nano12224023.

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In this work, highly fluorescent gold nanowire arrays (Au NWs) are successfully synthesized by assembling Zn2+ ions and non-emissive oligomeric gold-thiolate clusters using mercaptopropionic acid both as a reducing agent and a growth ligand. The synthesized Au NWs exhibited strong bluish green fluorescence with an absolute quantum yield up to 32% and possessed ultrasensitive pH stimuli-responsive performance in the range of 7.0–7.8. Based on the excellent properties of the as-prepared nanowire arrays, we developed a facile, sensitive, and selective fluorescent method for quantitative detection of urea and urease. The fabricated nanoprobe showed superior biosensing response characteristics with good linearities in the range of 0–100 μM for urea concentration and 0–12 U/L for urease activity. In addition, this fluorescent probe afforded relatively high sensitivity with the detection limit as low as 2.1 μM and 0.13 U/L for urea and urease, respectively. Urea in human urine and urease in human serum were detected with satisfied results, exhibiting a promising potential for biomedical application.

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17

Li, Luo, Zhen Li, Hui Zhang, Shoucun Zhang, Irfan Majeed, and Bien Tan. "Effect of polymer ligand structures on fluorescence of gold clusters prepared by photoreduction." Nanoscale 5, no. 5 (2013): 1986. http://dx.doi.org/10.1039/c2nr33693f.

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18

Gao, Duyang, Yubin Liu, Yating Wang, and Zhen Yuan. "Protein-modified ultra-small gold clusters for dual-modal in vivo fluorescence/photoacoustic imaging." Quantitative Imaging in Medicine and Surgery 8, no. 3 (April 2018): 326–32. http://dx.doi.org/10.21037/qims.2018.03.01.

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19

Du, Yanlin, Hui Liu, Jiaming Liang, Dongye Zheng, Jiong Li, Shubing Lan, Ming Wu, Aixian Zheng, and Xiaolong Liu. "Protein-assisted formation of gold clusters-MnO2 nanocomposite for fluorescence imaging of intracellular glutathione." Talanta 209 (March 2020): 120524. http://dx.doi.org/10.1016/j.talanta.2019.120524.

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20

Shang, Li, Naghmeh Azadfar, Florian Stockmar, Winfried Send, Vanessa Trouillet, Michael Bruns, Dagmar Gerthsen, and G. Ulrich Nienhaus. "One-Pot Synthesis of Near-Infrared Fluorescent Gold Clusters for Cellular Fluorescence Lifetime Imaging." Small 7, no. 18 (August 2, 2011): 2614–20. http://dx.doi.org/10.1002/smll.201100746.

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21

Tian, Ye, Ming Wei, Lijun Wang, Yuankai Hong, Dan Luo, and Yinlin Sha. "Two-Photon Time-Gated In Vivo Imaging of Dihydrolipoic-Acid-Decorated Gold Nanoclusters." Materials 14, no. 24 (December 15, 2021): 7744. http://dx.doi.org/10.3390/ma14247744.

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Due to the unique advantages of two-photon technology and time-resolved imaging technology in the biomedical field, attention has been paid to them. Gold clusters possess excellent physicochemical properties and low biotoxicity, which make them greatly advantageous in biological imaging, especially for in vivo animal imaging. A gold nanocluster was coupled with dihydrolipoic acid to obtain a functionalized nanoprobe; the material displayed significant features, including a large two-photon absorption cross-section (up to 1.59 × 105 GM) and prolonged fluorescence lifetime (>300 ns). The two-photon and time-resolution techniques were used to perform cell imaging and in vivo imaging.

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22

Cheng, Pearl Pui Hang, Debbie Silvester, Gangli Wang, Gregory Kalyuzhny, Alicia Douglas, and Royce W. Murray. "Dynamic and Static Quenching of Fluorescence by 1−4 nm Diameter Gold Monolayer-Protected Clusters." Journal of Physical Chemistry B 110, no. 10 (March 2006): 4637–44. http://dx.doi.org/10.1021/jp057028n.

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23

Mishra, Dinesh, Fadi Aldeek, Eric Lochner, Goutam Palui, Birong Zeng, Sebastian Mackowski, and Hedi Mattoussi. "Aqueous Growth of Gold Clusters with Tunable Fluorescence Using Photochemically Modified Lipoic Acid-Based Ligands." Langmuir 32, no. 25 (June 14, 2016): 6445–58. http://dx.doi.org/10.1021/acs.langmuir.6b00950.

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24

Yang, Guanhua, Han Zhang, Yueqi Wang, Xianhu Liu, Zhixun Luo, and Jiannian Yao. "Enhanced stability and fluorescence of mixed-proteins-protected gold/silver clusters used for mercury ions detection." Sensors and Actuators B: Chemical 251 (November 2017): 773–80. http://dx.doi.org/10.1016/j.snb.2017.05.019.

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25

Wang, Ruizhi, Guofeng Zhou, Yuchan Yang, Shiqing Wang, Shanshan Gao, Dongmei Gao, and Xiaolin Wang. "Prostate-Specific Membrane Antigen-1-Mediated Au@SiO₂@Au Core–Shell Nanoparticles: Targeting Prostate Cancer to Enhance Photothermal Therapy and Fluorescence Imaging." Journal of Biomedical Nanotechnology 18, no. 1 (January 1, 2022): 158–65. http://dx.doi.org/10.1166/jbn.2022.3229.

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The advantages of deep tissue penetration and the high spatial accuracy of photothermal therapy have been widely studied. Gold, as a photothermal material, has received particular attention. Different sizes and shapes of gold have been studied and characterized for their varying photothermal properties. The core–shell structure of gold nanoparticles and silica enhances the photothermal conversion through the coupling effect between gold clusters on the material’s surface. With excellent photothermal conversion performance, the core–shell nanoparticles can quickly reach 40 °C in 200 s under the irradiation of 808 nm, 1.5 W·cm−2. The highest conversion temperature of these nanoparticles is 56 °C, and the photothermal conversion rate is 45%. In vitro cell experiments displayed that NPs with targeted function can efficiently aggregate in prostate cancer cells and effectively kill cells. In vitro experiments showed that the tumor cells of mice after photothermal treatment completely disappeared after 15 days, which fully demonstrated the potential of the nanoparticles for targeted photothermal therapy.

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26

Polavarapu, Lakshminarayana, Manoj Manna, and Qing-Hua Xu. "Biocompatible glutathione capped gold clusters as one- and two-photon excitation fluorescence contrast agents for live cells imaging." Nanoscale 3, no. 2 (2011): 429–34. http://dx.doi.org/10.1039/c0nr00458h.

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27

Stelate, Ayoub, Eva Tihlaříková, Kateřina Schwarzerová, Vilém Neděla, and Jan Petrášek. "Correlative Light-Environmental Scanning Electron Microscopy of Plasma Membrane Efflux Carriers of Plant Hormone Auxin." Biomolecules 11, no. 10 (September 26, 2021): 1407. http://dx.doi.org/10.3390/biom11101407.

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Fluorescence light microscopy provided convincing evidence for the domain organization of plant plasma membrane (PM) proteins. Both peripheral and integral PM proteins show an inhomogeneous distribution within the PM. However, the size of PM nanodomains and protein clusters is too small to accurately determine their dimensions and nano-organization using routine confocal fluorescence microscopy and super-resolution methods. To overcome this limitation, we have developed a novel correlative light electron microscopy method (CLEM) using total internal reflection fluorescence microscopy (TIRFM) and advanced environmental scanning electron microscopy (A-ESEM). Using this technique, we determined the number of auxin efflux carriers from the PINFORMED (PIN) family (NtPIN3b-GFP) within PM nanodomains of tobacco cell PM ghosts. Protoplasts were attached to coverslips and immunostained with anti-GFP primary antibody and secondary antibody conjugated to fluorochrome and gold nanoparticles. After imaging the nanodomains within the PM with TIRFM, the samples were imaged with A-ESEM without further processing, and quantification of the average number of molecules within the nanodomain was performed. Without requiring any post-fixation and coating procedures, this method allows to study details of the organization of auxin carriers and other plant PM proteins.

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28

Schaeffer, Nicolas, Bien Tan, Calum Dickinson, Matthew J. Rosseinsky, Anna Laromaine, David W. McComb, Molly M. Stevens, et al. "Fluorescent or not? Size-dependent fluorescence switching for polymer-stabilized gold clusters in the 1.1–1.7 nm size range." Chemical Communications, no. 34 (2008): 3986. http://dx.doi.org/10.1039/b809876j.

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29

Prado, Adilson R., Danilo Oliveira de Souza, Jairo P. Oliveira, Rayssa H. A. Pereira, Marco C. C. Guimarães, Breno V. Nogueira, Pedro V. Dixini, Moisés R. N. Ribeiro, and Maria J. Pontes. "Probing the Sulfur-Modified Capping Layer of Gold Nanoparticles Using Surface Enhanced Raman Spectroscopy (SERS) Effects." Applied Spectroscopy 71, no. 12 (August 1, 2017): 2670–80. http://dx.doi.org/10.1177/0003702817724180.

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Gold nanoparticles (AuNP) exhibit particular plasmonic properties when stimulated by visible light, which makes them a promising tool to many applications in sensor technology and biomedical applications, especially when associated to sulfur-based compounds. Sulfur species form a great variety of self-assembled structures that cap AuNP and this interaction rules the optical and plasmonic properties of the system. Here, we report the behavior of citrate-stabilized gold nanospheres in two distinct sulfur colloidal solutions, namely, thiocyanate and sulfide ionic solutions. Citrate-capped gold nanospheres were characterized using ultraviolet–visible (UV-Vis) absorption, transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), and atomic force microscopy (AFM). In the presence of sulfur species, we have observed the formation of NP clusters and chain-like structures, giving rise to surface-enhanced effects. Surface-enhanced Raman spectroscopy (SERS) pointed to a modification in citrate vibrational modes, which suggests substitution of citrate by either thiocyanate or sulfide ions with distinct dynamics, as showed by in situ fluorescence. Moreover, we report the emergence of surface-enhanced infrared absorption (SEIRA) effect, which corroborates SERS conclusions. Further, SEIRA shows a great potential as a tool for specification of sulfur compounds in colloidal solutions, which is particularly useful when dealing with sensor technology.

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30

Naudon, A., and D. Thiaudiere. "Grazing-Incidence Small-Angle Scattering. Morphology of Deposited Clusters and Nanostructure of Thin Films." Journal of Applied Crystallography 30, no. 5 (October 1, 1997): 822–27. http://dx.doi.org/10.1107/s002188989700099x.

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It is shown that grazing-incidence small-angle X-ray scattering (GISAXS) is a new experimental technique that combines both grazing incidence and scattering at low angles. The experiments are carried out at or near the critical angle: the result is a considerably enhanced surface sensitivity. It allows morphological characterization of aggregates deposited or gathered on a flat substrate, such as silicon wafer or Coming glass. The full potential of this technique is realized when using a synchrotron source (flux, collimation and choice of wavelength in order to avoid fluorescence or to perform anomalous measurements) and when patterns are recorded with two-dimensional detectors: gas detectors or imaging plates (IPs). It is then possible to study the anisotropic shape of the scattering pattern and to determine the sizes of the aggregates. Results are presented for gold clusters deposited on a silicon wafer covered by a carbon sublayer in order to make a comparison with transmission electron microscopy and with scanning probe microscopy. Other examples are presented in order to highlight the advantages of such a technique applied to small inclusions in thin surface layers.

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31

Bonifazi, Giuseppe, Giuseppe Capobianco, Roberta Palmieri, and Silvia Serranti. "EVALUATION OF ELEMENTS DISTRIBUTION IN PRINTED CIRCUIT BOARDS FROM MOBILE PHONES BY MICRO X-RAY FLUORESCENCE." Detritus, no. 14 (March 31, 2021): 78–85. http://dx.doi.org/10.31025/2611-4135/2021.14067.

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A micro X-ray fluorescence-based approach for the chemical characterization of spent printed circuit boards (SPCB) from mobile phones was applied. More in detail, twelve spent mobile phones were grouped in three clusters depending on brands, models and release year and a study to evaluate the technological evolution of SPCBs over time was carried out. Precious and dangerous elements were investigated and some differences between samples belonging to the different groups were detected. For instance, the distribution of gold on the SPCB layers was more widespread for the older analyzed samples, and a smaller and smaller quantities of bromine and lead were detected in the more recent models in accordance with the Restriction of Hazardous Substances Directive 2002/95/EC. The analysis of SPCB composition can help to correctly manage such a complex waste, maximizing the recovery of base, critical and precious metals and considering the possible presence of harmful elements to be carefully managed. The experimental results showed as, through the proposed approach, it is possible to obtain chemical elements distribution maps of SPCBs surface, thus allowing to define optimal strategies for their further handling (i.e. classification) and processing (i.e. critical/precious metals recovery).

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32

Han, Ming, Yi Wang, Gang Xiang, Yinyin Chen, Zhouping Yang, Yunchun Li, Yu Zhang, Changfang Lu, and Xianxiang Wang. "Construction of ratiometric fluorescence determination of ethylene thiourea in foods based on the nanocomposite combining with sulfur quantum dots and gold clusters." Microchemical Journal 189 (June 2023): 108549. http://dx.doi.org/10.1016/j.microc.2023.108549.

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33

Hess, Michael W., Iris M. Krainer, Przemyslaw A. Filipek, Barbara Witting, Karin Gutleben, Ilja Vietor, Heinz Zoller, et al. "Advanced Microscopy for Liver and Gut Ultrastructural Pathology in Patients with MVID and PFIC Caused by MYO5B Mutations." Journal of Clinical Medicine 10, no. 9 (April 28, 2021): 1901. http://dx.doi.org/10.3390/jcm10091901.

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Mutations in the actin motor protein myosinVb (myo5b) cause aberrant apical cargo transport and the congenital enteropathy microvillus inclusion disease (MVID). Recently, missense mutations in myo5b were also associated with progressive familial intrahepatic cholestasis (MYO5B-PFIC). Here, we thoroughly characterized the ultrastructural and immuno-cytochemical phenotype of hepatocytes and duodenal enterocytes from a unique case of an adult MYO5B-PFIC patient who showed constant hepatopathy but only periodic enteric symptoms. Selected data from two other patients supported the findings. Advanced methods such as cryo-fixation, freeze-substitution, immuno-gold labeling, electron tomography and immuno-fluorescence microscopy complemented the standard procedures. Liver biopsies showed mislocalization of Rab11 and bile canalicular membrane proteins. Rab11-positive vesicles clustered around bile canaliculi and resembled subapical clusters of aberrant recycling endosomes in enterocytes from MVID patients. The adult patient studied in detail showed a severe, MVID-specific enterocyte phenotype, despite only a mild clinical intestinal presentation. This included mislocalization of numerous proteins essential for apical cargo transport and morphological alterations. We characterized the heterogeneous population of large catabolic organelles regarding their complex ultrastructure and differential distribution of autophagic and lysosomal marker proteins. Finally, we generated duodenal organoids/enteroids from biopsies that recapitulated all MVID hallmarks, demonstrating the potential of this disease model for personalized medicine.

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34

Powell, Richard D., Carol M. R. Halsey, David L. Spector, Shelley L. Kaurin, Jennifer McCann, and James F. Hainfeld. "A Covalent Fluorescent–Gold Immunoprobe: Simultaneous Detection of a Pre-mRNA Splicing Factor by Light and Electron Microscopy." Journal of Histochemistry & Cytochemistry 45, no. 7 (July 1997): 947–56. http://dx.doi.org/10.1177/002215549704500704.

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Immunoprobes that combine a fluorescent label with a 1.4-nm gold cluster compound have been prepared by covalent conjugation with polyclonal antibody Fab' fragments. These new immunoconjugates allow the collection of two complementary sets of data, from fluorescence and electron microscopy, from a single labeling experiment. We find that incorporation of one or more fluorescein moieties into the coordinated ligands of the 1.4-nm Nanogold gold cluster label yields a stable, dual-function immunolabel in which fluorescence quenching is negligible. In a second synthetic strategy, Nanogold and fluorescein were separately covalently conjugated to Fab' fragments to yield a probe with very similar properties. With the use of Fab' fragments, the entire probe is smaller than a whole IgG molecule, and it exhibited excellent penetration properties. It was used to localize the pre-mRNA splicing factor SC35 in the HeLa cell nucleus by both fluorescence and electron microscopy.

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35

Giraldo-Castillo, Nicolas A., Sneha Berry, Julie Stein, Benjamin Green, Peter Nguyen, Abha Soni, Farah Succaria, et al. "Multiplex Immunofluorescence Image Cytometry Combined with Spatially-Resolved UMAP Defines Novel Immune Prognostic Biomarkers in Metastatic Melanoma." Journal of Immunology 204, no. 1_Supplement (May 1, 2020): 243.3. http://dx.doi.org/10.4049/jimmunol.204.supp.243.3.

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Abstract Multiplex IF (mIF) provides a detailed characterization of spatial relationships and complex cell phenotypes in the tumor microenvironment. However, the data-analysis and visualization is complex and time-consuming. Here, we developed a platform to analyze mIF data through flow cytometry workflows (image cytometry), while maintaining spatial information, and applied it to tissue microarrays of metastatic melanoma specimens (n=93; 6-plex mIF panel: PD-1, PD-L1, CD163, CD8, FoxP3, Sox10/S100). Then, we used a UMAP-based approach driven by cell-to-cell distances (rather than fluorescence intensity) to display and analyze geographic organization and cell interactions. Our pipeline provided equivalent results to the digital pathology gold standard with faster run times (5-fold reduction) and higher reproducibility. We identified key prognostic immune variables, including CD8PD1Low and CD8PD1Neg cells which associated with longer overall survival (OS, both p<0.01), and CD163PDL1Neg cells which associated with shorter OS (p=0.001). The spatial UMAPs showed that PD-L1 and PD-1 intensities were spatially encoded, and their expression on distinct cell subsets was organized in geographic clusters. Specifically, PD-L1Hi cells co-located to areas of CD8 cells, and PD-1Hi cells were observed near dense collections of tumor cells. Spatial UMAP subtraction analysis (survivors vs. non-survivors at 5 years) identified geographic and co-expression signatures associated with improved prognosis, i.e. CD8-driven PD-L1 expression and lacking CD163PDL1Neg macrophages. These data demonstrate the use of image cytometry and spatial UMAPs for improved visualization and interpretation of single-cell, spatially-resolved mIF data.

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36

Powell, Richard D., Carol M. R. Halsey, Edmund Gutierrez, James F. Hainfeld, and Frederic R. Furuya. "Dual-Labeled Probes for Fluorescence and Electron Microscopy." Microscopy and Microanalysis 4, S2 (July 1998): 992–93. http://dx.doi.org/10.1017/s1431927600025083.

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Fluorescein and the 1.4 nm Nanogold cluster have been separately attached to polyclonal antibody Fab’ fragments to generate combined fluorescent and gold secondary antibody probes (1, 2), and in comparisons with Nanogold, colloidal gold and fluorescein-labeled secondary antibodies, neither label was found to be significantly compromised by the presence of the other. The proximity to a gold label with which a fluorophore retains sufficient fluorescence emission intensity to be useful is limited by non-radiative fluorescence resonance energy transfer (FRET) (3). This is a function of the degree of overlap of the fluorophore emission spectrum with the metal particle absorbtion spectrum, and of the separation of the metal particle and the fluorophore (4); for an effective dual-labeled probe, separation should be greater than the Forster distance (3), at which 50 % of excited-state decay occurs by FRET.

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37

Meijne, A. M., M. H. Driessens, G. La Riviere, D. Casey, C. A. Feltkamp, and E. Roos. "LFA-1 integrin redistribution during T-cell hybridoma invasion of hepatocyte cultures and manganese-induced adhesion to ICAM-1." Journal of Cell Science 107, no. 9 (September 1, 1994): 2557–66. http://dx.doi.org/10.1242/jcs.107.9.2557.

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We have reported previously that the integrin LFA-1 is essential for metastasis of T-cell hybridomas to the liver. We show here that hepatocytes isolated from normal non-inflamed rat liver express intercellular adhesion molecule-1 (ICAM-1) at the dorsal surface and more prominently at the lateral and substratum-adherent surfaces. Anti-rat ICAM-1 mAb inhibited adhesion of TAM8C4 T-cell hybridoma cells to hepatocytes. Invasion between hepatocytes was not affected, but this is probably due to lack of penetration of the mAb between the hepatocytes. In all hepatocyte-adherent TAM8C4 cells, LFA-1 was concentrated at the adhesion site. Redistribution of ICAM-1 to the interacting hepatocyte membrane was also seen, but only for part of the adherent TAM8C4 cells. LFA-1 was highly concentrated on pseudopods of invading TAM8C4 cells inserted between hepatocytes, and on the upper surface of invaded TAM8C4 cells located under the hepatocytes. ICAM-1 was concentrated in the hepatocyte membrane overlying TAM8C4 cells located underneath the monolayer. These results suggests that ICAM-1 is of major importance for liver invasion by these lymphoma cells. For optimal adhesion to ICAM-1, LFA-1 on T-cell hybridomas requires activation, which apparently occurs upon contact with cell layers that are invaded (G. La Riviere et al., J. Cell Sci. 107, 551–559, 1994). LFA-1 can be activated artificially by Mn2+. To study LFA-1 redistribution upon ICAM-1 interaction with higher resolution, we performed immuno-EM on cells before and after Mn(2+)-induced adhesion and spreading on immobilized ICAM-1. By immune fluorescence, LFA-1 was observed to redistribute to the ICAM-1-adherent surface, and to be concentrated in lamellipodia of spreading TAM8C4 cells. By immuno-EM, LFA-1 was localized in microclusters of approximately 10 gold particles. This was seen in cells fixed in suspension, and the size of these clusters did not change upon adhesion to ICAM-1. LFA-1 was present at high density in thin filopodia, but again in microclusters of similar size. Comparable results were obtained with a cytotoxic T-cell clone. We conclude that Mn(2+)-induced activation of LFA-1 is not associated with the formation or enlargement of LFA-1 clusters.

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38

McCabe, Chantal E., Erik Jessen, Daniel R. O'Brien, Julia E. Wiedmeier-Nutor, Susan L. Slager, and Esteban Braggio. "Abstract 3352: Identifying copy number variations in chronic lymphocytic leukemia using targeted next generation sequencing." Cancer Research 82, no. 12_Supplement (June 15, 2022): 3352. http://dx.doi.org/10.1158/1538-7445.am2022-3352.

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Abstract Chronic lymphocytic leukemia (CLL) is characterized by multiple copy number abnormalities (CNVs) with prognostic value. Identifying these structural variations is central to defining CLL pathogenesis, risk stratification, and therapeutic approaches. Fluorescence in situ hybridization (FISH) is the clinical gold standard in detecting prognostic CNVs in CLL. However, next-generation sequencing (NGS) techniques have become more readily available for clinical genomic applications and can also be used to identify CNVs. Here we present bioinformatic methods to accurately identify CNVs in CLL using NGS data. We used the CNV-calling algorithm PatternCNV to detect clinically relevant CNVs: deletion 17p13 [del(17p)], deletion 11q23 [del(11q)], deletion 13q14 [del(13q)], and trisomy 12. PatternCNV was run on 2274 samples (1500 somatic and 774 germline samples) from six different sequencing batches, screened using a targeted sequencing panel that covers all exons of 59 recurrently CLL mutated genes and additional amplicons covering the minimal affected regions of relevant CNVs. To correct for potential batch effects, PatternCNV was initially run to quantify exon coverage behavior without the chromosomes containing recurrent CNV events, 11, 12, 13, and 17. Principal component analyses and correlation matrices were analyzed, grouping the samples into four distinct clusters that contain similar exon coverage patterns. Samples in each of the four clusters were then independently re-run through PatternCNV using all chromosomes. Visual analysis of CNV plots revealed a bias in normalization. To correct this, the log2ratios were corrected to center the log ratio on the median coverage. Sample noisiness was calculated from the difference in the median absolute deviation (DiffMAD) and samples with a DiffMAD score greater than 0.3 were excluded. All CNV analyses were blinded to clinical FISH results. The effectiveness of our CNV calling was evaluated in 522 CLL patients who had FISH conducted within three months of the sample date. We excluded samples with low tumor metrics identified by FISH (less than 20% of cells with either del(17p), del(11q), trisomy 12 or del(13q)). When we compared our CNV analyses with the FISH data, we found high concordance 99.6% for del(17p), 97.5% for del(11p), 99.1% for trisomy 12, and 93.7% for del(13q). N=46 total discordant pairs were identified, with the highest discordance for del(13q), N=28, followed by del(11q), N=12. These novel bioinformatic methods allow for accurate detection of CNVs across NGS sequencing batches. The high concordance in detecting CNVs between targeted NGS and the gold standard of FISH, suggest NGS is an accurate tool for calling CNVs in CLL. Further, NGS can infer clinically relevant CNVs in genomic locations not targeted by FISH. Citation Format: Chantal E. McCabe, Erik Jessen, Daniel R. O'Brien, Julia E. Wiedmeier-Nutor, Susan L. Slager, Esteban Braggio. Identifying copy number variations in chronic lymphocytic leukemia using targeted next generation sequencing [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3352.

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39

Takizawa, Toshihiro, and John M. Robinson. "Analysis of Antiphotobleaching Reagents for use with FluoroNanogold in Correlative Microscopy." Journal of Histochemistry & Cytochemistry 48, no. 3 (March 2000): 433–36. http://dx.doi.org/10.1177/002215540004800313.

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Correlative microscopy is an important approach for bridging the resolution gap between fluorescence and electron microscopy. We have employed FluoroNanogold (FNG) as the detection system in these types of studies. This immunoprobe consists of a gold cluster compound to which a fluorochrome-labeled antibody is covalently linked. In these preparations, the fluorescence signal from FNG is first recorded then the gold cluster compound is subjected to a silver enhancement reaction before examination by electron microscopy. Potential complications are those associated with photochemical reactions that occur during fluorescence microscopy. We have evaluated this and some anti-photobleaching agents (i.e., 1,4-diazabicyclo[2.2.2]octane [DABCO], p-phenylenediamine [PPD], and N-propyl gallate [NPG]) for their utility with FNG in correlative microscopy. When DABCO was employed, the gold signal from FNG was dramatically diminished but the fluorescence signal was unaffected. The gold signal of DABCO-treated samples decreased to approximately 30% of that of the other samples. On the other hand, PPD and NPG did not adversely affect the FNG labeling. We recommend that either PPD or NPG be used and that DABCO be avoided as an antiphotobleaching reagent for this technique.

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40

Wang, Xiaojuan, Hua He, Yanan Wang, Junying Wang, Xing Sun, Hai Xu, Werner M. Nau, Xiaodong Zhang, and Fang Huang. "Active tumor-targeting luminescent gold clusters with efficient urinary excretion." Chemical Communications 52, no. 59 (2016): 9232–35. http://dx.doi.org/10.1039/c6cc03814j.

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41

Hainfeld, James F., and Richard D. Powell. "New Frontiers in Gold Labeling." Journal of Histochemistry & Cytochemistry 48, no. 4 (April 2000): 471–80. http://dx.doi.org/10.1177/002215540004800404.

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Recent advances in gold technology have led to probes with improved properties and performance for cell biologists: higher labeling density, better sensitivity, and greater penetration into tissues. Gold clusters, such as the 1.4-nm Nanogold, are gold compounds that can be covalently linked to Fab′ antibody fragments, making small and stable probes. Silver enhancement then makes these small gold particles easily visible by EM, LM, and directly by eye. Another advance is the combination of fluorescent and gold probes for correlative microscopy. Chemical crosslinking of gold particles to many biologically active molecules has made possible many novel probes, such as gold-lipids, gold-Ni-NTA, and gold-ATP.

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42

Powell, Richard D., Vishwas N. Joshi, Carol M. R. Halsey, James F. Hainfeld, Gerhard W. Hacker, Cornelia Hauser-Kronberger, Wolfgang H. Muss, and Peter M. Takvorian. "Combined Cy3 / Nanogold Conjugates for ImmunocytoChemistry and in Situ Hybridization." Microscopy and Microanalysis 5, S2 (August 1999): 478–79. http://dx.doi.org/10.1017/s1431927600015713.

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Fluorescein and the 1.4 nm Nanogold® gold cluster label may be incorporated into a single Fab’ immunoprobe by separate cross-linking reactions, to give a probe which labels antigenic sites in a single step for correlative fluorescence and electron microscope visualization. These probes show high labeling density, labeling a pre-mRNA splicing factor in the HeLa cell nucleus; Microtubules were also densely labeled using fluorescence, other optical modalities, and electron microscopy; in a parallel experiment, a 5 nm colloidal gold probe gave only occasional labeling. We now describe Fab’ and streptavidin probes containing both Nanogold® and the fluorescent cyanine dye, Cy3.F(ab’)2 Goat anti-Mouse IgG and F(ab’)2 goat anti-rabbit IgG fragments were reductively cleaved to Fab’ fragments using dithiothreitol (DTT) or mercaptoethylamine hydrochloride (MEA), which selectively reduce the F(ab’)2 hinge disulfide bonds, with 5 mm EDTA to prevent reoxidation. Fab’ fragments were isolated by gel filtration (coarse gel: GH25, Amicon) then labeled with Monomaleimido- Nanogold® which reacts site-specifically with thiols. Streptavidin was labeled using Mono- Sulfo-NHS-Nanogold® at pH 7.5. Nanogold® conjugates were isolated by gel filtration (Superose-12 column, Pharmacia), then reacted with excess Cy3 monofunctional NHS ester (labeling kit, Amersham Life Sciences) at pH 7.5; dual-labeled conjugates were isolated by gel filtration (Superose-12).

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43

Senthamizhan, Anitha, Asli Celebioglu, and Tamer Uyar. "Ultrafast on-site selective visual detection of TNT at sub-ppt level using fluorescent gold cluster incorporated single nanofiber." Chemical Communications 51, no. 26 (2015): 5590–93. http://dx.doi.org/10.1039/c4cc01190b.

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44

Antonishyn, Nick A., Ryan R. McDonald, Edward L. Chan, Greg Horsman, Carla E. Woodmansee, Pamela S. Falk, and C. Glen Mayhall. "Evaluation of Fluorescence-Based Amplified Fragment Length Polymorphism Analysis for Molecular Typing in Hospital Epidemiology: Comparison with Pulsed-Field Gel Electrophoresis for Typing Strains of Vancomycin-Resistant Enterococcus faecium." Journal of Clinical Microbiology 38, no. 11 (2000): 4058–65. http://dx.doi.org/10.1128/jcm.38.11.4058-4065.2000.

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Fluorescence-based amplified fragment length polymorphism (fbAFLP) is a novel assay based on the fluorescent analysis of an amplified subset of restriction fragments. The fbAFLP assay involves the selective PCR amplification of restriction fragments from a total digest of genomic DNA. The ligation of adapters with primer-specific sites coupled with primers containing selective nucleotides allowed the full potential of PCR to be realized while maintaining the advantages of restriction endonuclease analysis. Fluorescence-based fragment analysis with polyacrylamide gel electrophoresis provides the accurate band sizing required for homology assessment. The large number of phylogenetically informative characters obtained by fbAFLP is well suited for cluster analysis and database development. The method demonstrated excellent reproducibility and ease of performance and interpretation. We typed 30 epidemiologically well-characterized isolates of vancomycin-resistant enterococci from an outbreak in a university hospital by fbAFLP. Clustering of fbAFLP data matched epidemiological, microbiological, and pulsed-field gel electrophoresis data. This study demonstrates the unprecedented utility of fbAFLP for epidemiological investigation. Future developments in standardization and automation will set fbAFLP as the “gold standard” for molecular typing in epidemiology.

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45

Nair, L. V., R. V. Nair, S. J. Shenoy, A. Thekkuveettil, and R. S. Jayasree. "Blood brain barrier permeable gold nanocluster for targeted brain imaging and therapy: an in vitro and in vivo study." Journal of Materials Chemistry B 5, no. 42 (2017): 8314–21. http://dx.doi.org/10.1039/c7tb02247f.

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46

Prisco, Umberto, Carl Leung, Chrisa Xirouchaki, Celine H. Jones, John K. Heath, and Richard E. Palmer. "Residue-specific immobilization of protein molecules by size-selected clusters." Journal of The Royal Society Interface 2, no. 3 (May 11, 2005): 169–75. http://dx.doi.org/10.1098/rsif.2005.0032.

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The atomic force microscope (AFM), operating in contact mode, has been employed in buffer solution to study two proteins; (i) green fluorescent protein (GFP), from the hydromedusan jellyfish Aequorea victoria ; and (ii) human oncostatin M (OSM), in the presence of size-selected gold nanoclusters pinned on to a highly oriented pyrolytic graphite substrate. The AFM images have revealed immobilization of single molecules of OSM, which are strongly bound to the gold nanoclusters. Conversely, no strong immobilization has been observed for the GFP, as these molecules were easily displaced by the scanning tip. The contrasting behaviour of the two proteins can be explained by the exposed molecular surface area of their cysteine residues as modelled on the basis of their respective X-ray crystallographic data structures. GFP contains two cysteine residues, but neither is readily available to chemisorb on the gold clusters, because the cysteines are largely inaccessible from the surface of the protein. In contrast, OSM has a total of five cysteine residues, with different degrees of accessibility, which make the protein amenable to anchoring on the nanoclusters. Statistical analysis of the height of the OSM molecules bound to the nanoclusters is in accordance with crystallographic data, and suggests various configurations of the proteins on the clusters, associated with the presence of different cysteine anchoring sites. These results suggest that the three-dimensional conformation of protein molecules is preserved when they are chemisorbed to size-selected gold clusters, thus opening a new route towards oriented immobilization of individual protein molecules.

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47

Phuc, Lam Gia, Phuong Que Tran Do, Hanh Kieu Thi Ta, Vinh Quang Dang, Sang-Woo Joo, Do Hung Manh, Ta Ngoc Bach, Tran T. T. Van, and Nhu Hoa Thi Tran. "Metal-Enhanced Fluorescence for Alpha-Fetoprotein Detection and for SERS Using Hybrid Nanoparticles of Magnetic Cluster Core—Plasmonic Shell Composite." Chemosensors 11, no. 1 (January 9, 2023): 56. http://dx.doi.org/10.3390/chemosensors11010056.

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We demonstrated that the hybrid core–shell nanostructure of Fe3O4 (core) and gold (shell) could be a good substrate candidate both for metal-enhanced fluorescence (MEF) and surface-enhanced Raman spectroscopy (SERS). The magnetic properties of the core material could provide functionalities such as the magnetically induced aggregation/distribution of nanostructures to increase the hot-spot density, while the nano-thickness gold shell allows for the plasmonic enhancement of both fluorescence and SERS. The gold-capped magnetic (Fe3O4) nanoparticles (GMPs) were facilely synthesized using a newly developed chemical method. The relative molar ratio of the constituent materials of the core–shell composite was optimized for tuning the plasmonic resonance wavelengths for MEF and SERS. We employed GMP-based MEF to detect alpha-fetoprotein (AFP), with concentrations ranging from 0.05 to 1000 ng/mL, and obtained a limit of detection (LOD) as low as 3.8 × 10−4 ng/mL. The signal enhancement factor (EF) in the GMP-based MEF was 1.5 at maximum. In addition, the GMPs were used in SERS to detect rhodamine B (RhB). Its LOD was 3.5 × 10−12 M, and the EF was estimated to be about 2 × 108. The hybrid core–shell nanoparticles could find potential applications in diagnostic assays based on MEF and SERS in various fields such as food verification, environmental testing/monitoring, and disease diagnosis.

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48

Wu, Haiming, Ye-Guang Fang, Rajini Anumula, Gaya N. Andrew, Ganglong Cui, Weihai Fang, Zhixun Luo, and Jiannian Yao. "A mono-copper doped undeca-gold cluster with up-converted and anti-stokes emissions of fluorescence and phosphorescence." Nanoscale 13, no. 10 (2021): 5300–5306. http://dx.doi.org/10.1039/d0nr07624d.

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We have synthesized single crystals of a highly stable Cu-doped undeca-gold cluster protected by both triphenylphosphine (PPh₃) and 2-pyridinethiol (-SPy) ligands, formulated as [Au₁₁Cu₁(PPh₃)₇(SPy)₃]⁺.

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49

Samanta, Anupam, Basab B. Dhar, and R. Nandini Devi. "Ultrasmall Gold Cluster Arrays Encapsulated in Silica Nanospheres: Applications in Fluorescence Imaging and Catalysis." Journal of Physical Chemistry C 116, no. 2 (January 10, 2012): 1748–54. http://dx.doi.org/10.1021/jp2093737.

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50

Esteve, Emmanuel, Solenn Reguer, Cédric Boissiere, Corinne Chanéac, Gustavo Lugo, Chantal Jouanneau, Cristian Mocuta, et al. "Flyscan opportunities in medicine: the case of quantum rattle based on gold quantum dots." Journal of Synchrotron Radiation 24, no. 5 (August 7, 2017): 991–99. http://dx.doi.org/10.1107/s1600577517009572.

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The new rapid scan method, Flyscan mode, implemented on the DiffAbs beamline at Synchrotron SOLEIL, allows fast micro-X-ray fluorescence data acquisition. It paves the way for applications in the biomedical field where a large amount of data is needed to generate meaningful information for the clinician. This study presents a complete set of data acquired after injection of gold-cluster-enriched mesoporous silica nanospheres, used as potential theranostic vectors, into rats. While classical X-ray fluorescence investigations (using step-by-step acquisitions) are based on a limited number of samples (approximately one per day at the DiffAbs beamline), the Flyscan mode has enabled gathering information on the interaction of nanometer-scale vectors in different organs such as liver, spleen and kidney at the micrometer scale, for five rats, in only a single five-day synchrotron shift. Moreover, numerous X-ray absorption near-edge structure spectra, which are beam-time-consuming taking into account the low concentration of these theranostic vectors, were collected.

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