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Статті в журналах з теми "Free gold"

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Автор: Grafiati

Опубліковано: 10 грудня 2022

Оновлено: 28 січня 2023

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1

Andreescu, Daniel, Tapan Kumar Sau, and Dan V. Goia. "Stabilizer-free nanosized gold sols." Journal of Colloid and Interface Science 298, no. 2 (June 2006): 742–51. http://dx.doi.org/10.1016/j.jcis.2006.01.011.

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2

Jin, Yongdong, and Xiaohu Gao. "Spectrally Tunable Leakage-Free Gold Nanocontainers." Journal of the American Chemical Society 131, no. 49 (December 16, 2009): 17774–76. http://dx.doi.org/10.1021/ja9076765.

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3

Appel, Peter Wiltje Uitterdijk, and Leoncio Degay Na-Oy. "Mercury-Free Gold Extraction Using Borax for Small-Scale Gold Miners." Journal of Environmental Protection 05, no. 06 (2014): 493–99. http://dx.doi.org/10.4236/jep.2014.56052.

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4

Toktar, G., A. K. Koizhanova, D. R. Magomedov, N. N. Abdyldaev, and A. N. Bakraeva. "Increased recovery of free fine gold in the leaching process." Kompleksnoe Ispolʹzovanie Mineralʹnogo syrʹâ/Complex Use of Mineral Resources/Mineraldik Shikisattardy Keshendi Paidalanu 322, no. 3 (May 2, 2022): 51–58. http://dx.doi.org/10.31643/2022/6445.28.

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Анотація:

The current state of world mineral resources is characterized by a decrease in the quality of minerals. An increase in production and processing volumes is possible only through the development of new deposits and the involvement of off-balance ores, dumps and tailings, slags and other industrial wastes in the integrated mining process. More increasing the need for involving raw materials of complex composition, refractory, low-grade, with small reserves, technogenic mineral waste. It becomes more and more relevant as the discovery and exploitation of new deposits, allowing to increase the gold reserve of the Republic of Kazakhstan. The article presents the results of sorption leaching of ore in order to extract gold associated with sulfides, the processes of opening gold. A representative sample was taken and the phase composition of an additional explored ore body was studied at one of the deposits in Kazakhstan. The ore sample was prepared for research: three-time mixing by the ring-cone method, in general, three-stage quarting and mixing were performed. It should be noted that the methods for processing gold-bearing ore raw materials depend on many parameters, including the material composition and technological properties. Samples from the last quarting materials were selected for chemical, sieve and phase analyzes. It was found that the test sample contained 6.04 g / t Au and 7.9 g / t Ag, as well as fineness of gold within 0.01-0.25 mm phase analysis. Mineral gold formations can be easily soluble in cyanide solutions (native gold, electrum), partially soluble (maldonite, or practical are insoluble (tellurides). Gold in ores is present in the form of gold-colored sizes and shapes. Both physical (gravity, flotation) and chemical (cyanide, etc.) methods are used to extract it. Rational analysis also found that gold in the ore under study, crushed to a particle size of 90%, class 0.071 mm, gold is free and in intergrowths is 81.46%, gold associated with sulfides is 14.40%, in rock-forming minerals 1.66%. Based on the data obtained, it can be stated that when cyanidating ore, one should expect rather high rates of gold dissolution (80% or more). Gold extraction from ore with a content of 85% fraction -0.071mm-90.2%, with a content of 85% fraction- 0.071mm-98% with oxidative leaching. Full extraction of gold from ore is possible with sorption cyanide leaching with their preliminary oxidation. The paper considers economically feasible existing and promising technologies for gold extraction at the leading factories of Kazakhstan and abroad.

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5

Li, Cheng Chao, Li Bao Chen, Qiu Hong Li, and Tai Hong Wang. "Seed-free, aqueous synthesis of gold nanowires." CrystEngComm 14, no. 22 (2012): 7549. http://dx.doi.org/10.1039/c2ce25726b.

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6

Lemasters, Robert, Cheng Zhang, Manoj Manjare, Wenqi Zhu, Junyeob Song, Sergei Urazhdin, Henri J. Lezec, Amit Agrawal, and Hayk Harutyunyan. "Ultrathin Wetting Layer-Free Plasmonic Gold Films." ACS Photonics 6, no. 11 (October 3, 2019): 2600–2606. http://dx.doi.org/10.1021/acsphotonics.9b00907.

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7

Wang, Xuelu, Chunyang Wang, Chunjin Chen, Huichao Duan, and Kui Du. "Free-standing Monatomic Thick Two-dimensional Gold." Nano Letters 19, no. 7 (June 24, 2019): 4560–66. http://dx.doi.org/10.1021/acs.nanolett.9b01494.

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8

Reilly, Samantha M., Thomas Krick, and Amala Dass. "Surfactant-free Synthesis of Ultrasmall Gold Nanoclusters." Journal of Physical Chemistry C 114, no. 2 (December 23, 2009): 741–45. http://dx.doi.org/10.1021/jp9067944.

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9

Solorio-Alvarado, César R., and Antonio M. Echavarren. "Gold-Catalyzed Annulation/Fragmentation: Formation of Free Gold Carbenes by Retro-Cyclopropanation." Journal of the American Chemical Society 132, no. 34 (September 2010): 11881–83. http://dx.doi.org/10.1021/ja104743k.

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10

Alemayehu, Abraham B., and Abhik Ghosh. "Gold corroles." Journal of Porphyrins and Phthalocyanines 15, no. 02 (February 2011): 106–10. http://dx.doi.org/10.1142/s1088424611003045.

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Анотація:

Although a variety of conditions proved unsuccessful for gold insertion into β-unsubstituted meso-triarylcorroles, refluxing free-base β-octabromo-meso-triarylcorrole ligands, H3[Br8T (p- X-P)C] ( X = MeO , n- Bu , CH3 , H , and CF3 ), with chloroauric acid in dichloromethane containing a small amount of triethylamine for 30 min led to 54–65% yields of the corresponding gold complexes.

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11

Appel, Peter W. U., Astrid Andersen, Leoncio D. Na-Oy, and Rudy Onos. "Introduction of Mercury-free Gold Extraction Methods to Medium-Scale Miners and Education of Health Care Providers to Reduce the use of Mercury in Sorata, Bolivia." Journal of Health and Pollution 5, no. 9 (December 1, 2015): 12–17. http://dx.doi.org/10.5696/2156-9614-5-9.12.

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Анотація:

Background. Artisanal and small-scale miners in Bolivia release on the order of 120 tons of mercury annually. The mercury finds its way to the Amazon with catastrophic consequences for the biosphere. A project aimed at reducing the release of mercury was carried out in 2013 and 2014. Objectives. The project had two objectives: to test whether the mercury-free gold extraction method could be an alternative to whole ore amalgamation in medium-scale mining in Bolivia and to teach mercury toxicology to health care providers in the gold mining area. The mercury-free gold extraction method has been successfully introduced in other countries, but mainly in very small-scale mining communities. Materials and Methods. The targets in Bolivia were medium-scale miners processing over a hundred tons of ore per day. The chosen gold ores proved amenable to gold extraction using mercury-free extraction. Demonstrations of the mercury-free methods were carried out by processing similar quantities of gold ores using the amalgamation and the mercury-free method. Miners, mining communities and local health providers were informed on the toxicity of mercury. Health providers were shown how to conduct epidemiological surveillance. Posters explaining the path of mercury from the processing stations to local households were prepared. Conclusions. The gold ores tested during the project proved amenable to mercury-free gold extraction using borax smelting. The miners also realized that gold recovery increased when performing mercury-free gold extraction. The miners decided to stop using mercury and a follow-up project cleaned their mining equipment for mercury and modified the processing lines. The health care providers were also successfully trained.

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12

Schmidbaur, Hubert, and Annette Schier. "Silver-free Gold(I) Catalysts for Organic Transformations." Zeitschrift für Naturforschung B 66, no. 4 (April 1, 2011): 329–50. http://dx.doi.org/10.1515/znb-2011-0401.

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Анотація:

The majority of gold(I) catalysts employed in organic transformations in homogeneous systems are presently generated in situ by reactions of gold halides AuX or their 1 : 1 complexes [(L)AuX] with silver salts AgY (X = Cl, Br; L = R3P, NHC, tht etc.; Y = BF4, PF6, SbF6, OSO2CF3, OC(O)CF3 etc.). This usage of silver salts is not only economically unfavorable, but also has several practical disadvantages regarding inter alia the thermal and photochemical stability of the reaction mixtures, problems of inexact stoichiometries, difficulties in separation and recycling, and cooperative effects due to Au-Ag metallophilic interactions which can induce a different course of the reactions. There is therefore a move towards syntheses of silver-free homogeneous gold(I) catalysts. The past and current approaches and opportunities are summarized in this review.

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13

Zhang, Qiang, Biao Zang, and Shaozhen Wang. "Surfactant-free synthesis of porous Au by a urea complex." RSC Advances 9, no. 40 (2019): 23081–85. http://dx.doi.org/10.1039/c9ra04372a.

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14

Schoner, Claudia, André Tuchscherer, Thomas Blaudeck, Stephan F. Jahn, Reinhard R. Baumann, and Heinrich Lang. "Particle-free gold metal–organic decomposition ink for inkjet printing of gold structures." Thin Solid Films 531 (March 2013): 147–51. http://dx.doi.org/10.1016/j.tsf.2013.01.027.

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15

Elbra, Ainsley. "Fool’s Gold: Business Power and the Evolution of the Conflict‐free Gold Standard." Global Policy 11, no. 3 (March 11, 2020): 336–46. http://dx.doi.org/10.1111/1758-5899.12804.

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16

Solorio-Alvarado, Cesar R., and Antonio M. Echavarren. "ChemInform Abstract: Gold-Catalyzed Annulation/Fragmentation: Formation of Free Gold Carbenes by Retrocyclopropanation." ChemInform 42, no. 6 (January 13, 2011): no. http://dx.doi.org/10.1002/chin.201106112.

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17

Stoffersen, Birgitte, Rasmus Køster-Rasmussen, Jorge Ivan Contreras Cardeño, Peter W. U. Appel, Margrethe Smidth, Leoncio D. Na-Oy, Debbie Libua Lardizabal, and Rudy W. Onos. "Comparison of Gold Yield with Traditional Amalgamation and Direct Smelting in Artisanal Small-Scale Gold Mining in Uganda." Journal of Health and Pollution 9, no. 24 (November 27, 2019): 191205. http://dx.doi.org/10.5696/2156-9614-9.24.191205.

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Анотація:

Background. The amalgamation method used by artisanal small-scale miners is the single largest source of global mercury emission. The goal of the ‘Free Your Mine’ project is to stop mercury use in artisanal and small-scale mining. Objectives. The aim of the present study was to compare gold recovery and time consumption between the amalgamation method and direct smelting, using borax for smelting under standardized conditions. Materials and Methods. This was an experimental study in a pragmatic setting in the mining community of Tiira, Uganda. Standardized amounts of gold ore of equal quality were processed with the local amalgamation method and with the Philippine mercury-free method as practiced by miners from Benguet in the Philippines, and the gold yield and time consumption were compared. Results. The amalgamation method took 53 minutes and recovered 1.0 g of pure gold. The miners used 4 g of mercury in the processing. The Philippine mercury-free method took 62 minutes and recovered 1.4 g of pure gold. Conclusions. The Philippine mercury-free method recovered 40% more gold than the amalgamation method but took 9 minutes longer. The Philippine mercury-free method is a viable alternative to amalgamation. Competing Interests. The authors declare no competing financial interests.

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18

Razmakhnin, KK, and PA Vasiljuk. "Technological and environmental features of heap leaching of Delmachik gold-bearing ores deposit." IOP Conference Series: Earth and Environmental Science 991, no. 1 (February 1, 2022): 012044. http://dx.doi.org/10.1088/1755-1315/991/1/012044.

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Abstract The problem of gold ores hydrometallurgical processing with using sodium cyanide is evaluated. The prospects for the development of the use of cyanide-free reagents for leaching gold from ores are studied. The possibility of introducing a cyanide-free environmentally friendly reagent instead of the widely used sodium cyanide was determined. The results of experimental studies on the comparability of the processing of gold ores using sodium cyanide and a reagent based on sodium cyanoate are obtained. The optimal parameters of the technological process for the extraction of gold from ores using a cyanide-free reagent are established.

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19

Gomes, Axel, Jose M. Carnerero, Aila Jimenez-Ruiz, Elia Grueso, Rosa M. Giráldez-Pérez, and Rafael Prado-Gotor. "Lysozyme–AuNPs Interactions: Determination of Binding Free Energy." Nanomaterials 11, no. 8 (August 22, 2021): 2139. http://dx.doi.org/10.3390/nano11082139.

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Investigation and optimization of lysozyme (Lys) adsorption onto gold nanoparticles, AuNPs, were carried out. The purpose of this study is to determine the magnitude of the AuNPs–lysozyme interaction in aqueous media by simple spectrophotometric means, and to obtain the free energy of binding of the system for the first time. In order to explore the possibilities of gold nanoparticles for sensing lysozyme in aqueous media, the stability of the samples and the influence of the gold and nanoparticle concentrations in the detection limit were studied. ζ potential measurements and the shift of the surface plasmon band showed a state of saturation with an average number of 55 Lys per gold nanoparticle. Lysozyme–AuNPs interactions induce aggregation of citrate-stabilized AuNPs at low concentrations by neutering the negative charges of citrate anions; from those aggregation data, the magnitude of the interactions has been measured by using Benesi–Hildebrand plots. However, at higher protein concentrations aggregation has been found to decrease. Although the nanocluster morphology remains unchanged in the presence of Lys, slight conformational changes of the protein occur. The influence of the size of the nanoclusters was also investigated for 5, 10, and 20 nm AuNPs, and 10 nm AuNPs was found the most appropriate.

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20

Ciobanu, C. L., N. J. Cook, S. Utsunomiya, M. Kogagwa, L. Green, S. Gilbert, and B. Wade. "Gold-telluride nanoparticles revealed in arsenic-free pyrite." American Mineralogist 97, no. 8-9 (August 1, 2012): 1515–18. http://dx.doi.org/10.2138/am.2012.4207.

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21

Schmidbaur, H., and A. Schier. "Silver-free Gold(I) Catalysts for Organic Transformations." Zeitschrift für Naturforschung B 66 (2011): 0329. http://dx.doi.org/10.5560/znb.2011.66b0329.

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22

Nanda, K. K., A. Maisels, and F. E. Kruis. "Surface Tension and Sintering of Free Gold Nanoparticles." Journal of Physical Chemistry C 112, no. 35 (August 12, 2008): 13488–91. http://dx.doi.org/10.1021/jp803934n.

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23

Otte, Franziska L., Sonja Lemke, Christian Schütt, Nicolai R. Krekiehn, Ulrich Jung, Olaf M. Magnussen, and Rainer Herges. "Ordered Monolayers of Free-Standing Porphyrins on Gold." Journal of the American Chemical Society 136, no. 32 (August 2014): 11248–51. http://dx.doi.org/10.1021/ja505563e.

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24

Alshammari, Hamed, Peter J. Miedziak, Thomas E. Davies, David J. Willock, David W. Knight, and Graham J. Hutchings. "Initiator-free hydrocarbon oxidation using supported gold nanoparticles." Catal. Sci. Technol. 4, no. 4 (2014): 908–11. http://dx.doi.org/10.1039/c4cy00088a.

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25

Castellana, Edward T., Roberto C. Gamez, and David H. Russell. "Label-Free Biosensing with Lipid-Functionalized Gold Nanorods." Journal of the American Chemical Society 133, no. 12 (March 30, 2011): 4182–85. http://dx.doi.org/10.1021/ja109936h.

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26

Schulz-Dobrick, Martin, K. Vijaya Sarathy, and Martin Jansen. "Surfactant-Free Synthesis and Functionalization of Gold Nanoparticles." Journal of the American Chemical Society 127, no. 37 (September 2005): 12816–17. http://dx.doi.org/10.1021/ja054734t.

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27

Morral, A. Fontcuberta i. "Gold-Free GaAs Nanowire Synthesis and Optical Properties." IEEE Journal of Selected Topics in Quantum Electronics 17, no. 4 (July 2011): 819–28. http://dx.doi.org/10.1109/jstqe.2010.2091259.

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28

Franz, Gerhard, Wolfhard Oberhausen, Ralf Meyer, and Markus-Christian Amann. "Residual-free reactive ion etching of gold layers." AIP Advances 8, no. 7 (July 2018): 075026. http://dx.doi.org/10.1063/1.5037886.

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29

Städler, Brigitte, Harun H. Solak, Susanne Frerker, Kristien Bonroy, Filip Frederix, Janos Vörös, and H. Michelle Grandin. "Nanopatterning of gold colloids for label-free biosensing." Nanotechnology 18, no. 15 (March 9, 2007): 155306. http://dx.doi.org/10.1088/0957-4484/18/15/155306.

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30

Schwartz, Osip, and Dan Oron. "Background-Free Third Harmonic Imaging of Gold Nanorods." Nano Letters 9, no. 12 (December 9, 2009): 4093–97. http://dx.doi.org/10.1021/nl902305w.

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31

Chen, L. Y., X. Y. Lang, T. Fujita, and M. W. Chen. "Nanoporous gold for enzyme-free electrochemical glucose sensors." Scripta Materialia 65, no. 1 (June 2011): 17–20. http://dx.doi.org/10.1016/j.scriptamat.2011.03.025.

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32

Shakiba, Amin, Shreya Shah, Andrew C. Jamison, Irene Rusakova, Tai-Chou Lee, and T. Randall Lee. "Silver-Free Gold Nanocages with Near-Infrared Extinctions." ACS Omega 1, no. 3 (September 21, 2016): 456–63. http://dx.doi.org/10.1021/acsomega.6b00134.

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33

Apyari, Vladimir V., Stanislava G. Dmitrienko, Viktoriya V. Arkhipova, Aydar G. Atnagulov, and Yuri A. Zolotov. "Determination of cysteamine using label-free gold nanoparticles." Analytical Methods 4, no. 10 (2012): 3193. http://dx.doi.org/10.1039/c2ay25675d.

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34

Beret, Elizabeth C., Luca M. Ghiringhelli, and Matthias Scheffler. "Free gold clusters: beyond the static, monostructure description." Faraday Discussions 152 (2011): 153. http://dx.doi.org/10.1039/c1fd00027f.

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35

Juárez, Raquel, Patricia Concepción, Avelino Corma, Vicente Fornés, and Hermenegildo García. "Gold-Catalyzed Phosgene-Free Synthesis of Polyurethane Precursors." Angewandte Chemie International Edition 49, no. 7 (January 18, 2010): 1286–90. http://dx.doi.org/10.1002/anie.200905160.

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36

Juárez, Raquel, Patricia Concepción, Avelino Corma, Vicente Fornés, and Hermenegildo García. "Gold-Catalyzed Phosgene-Free Synthesis of Polyurethane Precursors." Angewandte Chemie 122, no. 7 (February 8, 2010): 1308–12. http://dx.doi.org/10.1002/ange.200905160.

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37

Bel'kov, M. V., V. S. Burakov, V. V. Kiris, N. M. Kozhukh, and S. N. Raikov. "Spectral Standard-Free Laser Microanalysis of Gold Alloys." Journal of Applied Spectroscopy 72, no. 3 (May 2005): 376–81. http://dx.doi.org/10.1007/s10812-005-0085-6.

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38

Dupuy, Stéphanie, Alexandra M. Z. Slawin, and Steven P. Nolan. "The Fluoride-Free Transmetalation of Organosilanes to Gold." Chemistry - A European Journal 18, no. 47 (October 12, 2012): 14923–28. http://dx.doi.org/10.1002/chem.201202299.

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39

Lebedev, Ivan. "Development of a new lining ball mill model for commercial component preservation." E3S Web of Conferences 192 (2020): 02005. http://dx.doi.org/10.1051/e3sconf/202019202005.

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At present the main aggregates for fine grinding of gold ores are ball and similar mills, in which in addition to mass ore grinding, deformation and free gold destruction occurs. The article aims to study the process of deformation of free gold extracted during grinding and to develop a ball mill design to preserve the commercial component.

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40

Barone, Carlo, Monica Bertoldo, Raffaella Capelli, Franco Dinelli, Piera Maccagnani, Nadia Martucciello, Costantino Mauro, and Sergio Pagano. "Electric Transport in Gold-Covered Sodium–Alginate Free-Standing Foils." Nanomaterials 11, no. 3 (February 24, 2021): 565. http://dx.doi.org/10.3390/nano11030565.

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The electric transport properties of flexible and transparent conducting bilayers, realized by sputtering ultrathin gold nanometric layers on sodium–alginate free-standing films, were studied. The reported results cover a range of temperatures from 3 to 300 K. In the case of gold layer thicknesses larger than 5 nm, a typical metallic behavior was observed. Conversely, for a gold thickness of 4.5 nm, an unusual resistance temperature dependence was found. The dominant transport mechanism below 70 K was identified as a fluctuation-induced tunneling process. This indicates that the conductive region is not continuous but is formed by gold clusters embedded in the polymeric matrix. Above 70 K, instead, the data can be interpreted using a phenomenological model, which assumes an anomalous expansion of the conductive region upon decreasing the temperature, in the range from 300 to 200 K. The approach herein adopted, complemented with other characterizations, can provide useful information for the development of innovative and green optoelectronics.

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41

Ofori-Sarpong, Grace, Kwadwo Osseo-Asare, and Ming Tien. "Pretreatment of Refractory Gold Ores Using Cell-Free Extracts of P. chrysosporium: A Preliminary Study." Advanced Materials Research 825 (October 2013): 427–30. http://dx.doi.org/10.4028/www.scientific.net/amr.825.427.

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The fungus Phanerochaete chrysosporium has been proven to biotransform refractory gold ores, leading to increase in gold recovery. This transformation has been attributed to enzymes secreted by the microbe. This paper reports the findings of preliminary investigations aimed at assessing the use of hydrogen peroxide and cell-free extracts from the fungus, P. chrysosporium, to effect biotransformation of sulphidic refractory gold ores. The investigations show that the total dissolved arsenic, iron and sulphur in solution were up to 5.2 wt%, 0.9 wt% and 6.0 wt% respectively from flotation concentrate after 72 hrs of treatment. Analysis for sulphide sulphur in the residual solids of the gold concentrate indicated about 25 wt% oxidation within 24 hours of treatment. In general, cell-free decomposition of the samples did not increase beyond 24 hours of contact time, possibly due to exhaustion of the active components. Gold extraction by cyanidation increased by 24% after 24-hr treatment with the cell-free extracts. Comparatively, cell-free (in vitro) treatment recorded 66% overall gold recovery as against 61% for whole cell (in vivo) after 72 hours of treatment. These initial results indicate clearly that in vitro processing is a promising alternative to in vivo processing of refractory gold ores using P. chrysosporium.

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42

Amankwah, R. K., A. U. Khan, C. A. Pickles, and W. T. Yen. "Improved grindability and gold liberation by microwave pretreatment of a free-milling gold ore." Mineral Processing and Extractive Metallurgy 114, no. 1 (April 2005): 30–36. http://dx.doi.org/10.1179/037195505x28447.

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43

Tong, Ping, Shurong Tang, Yu He, Yanhong Shao, Lan Zhang, and Guonan Chen. "Label-free immunosensing of microcystin-LR using a gold electrode modified with gold nanoparticles." Microchimica Acta 173, no. 3-4 (February 19, 2011): 299–305. http://dx.doi.org/10.1007/s00604-011-0557-8.

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Mie, Yasuhiro, Hirotaka Okabe, Chitose Mikami, Taisei Motomura, and Naoki Matsuda. "Nanostructured gold thin film electrode derived from surfactant-free gold nanoparticles for enhanced electrocatalysis." Electrochemistry Communications 146 (January 2023): 107415. http://dx.doi.org/10.1016/j.elecom.2022.107415.

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Saini, Meenaxi, Yogeshwar Masirkar, Ritu Varshney, Partha Roy, and Kalyan K. Sadhu. "Fluorogen-free aggregation induced NIR emission from gold nanoparticles." Chemical Communications 53, no. 46 (2017): 6199–202. http://dx.doi.org/10.1039/c7cc00641a.

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Ren, Xuefeng, Ying Song, Anmin Liu, Jie Zhang, Peixia Yang, Jinqiu Zhang, Guohui Yuan, Maozhong An, Hannah Osgood, and Gang Wu. "Role of polyethyleneimine as an additive in cyanide-free electrolytes for gold electrodeposition." RSC Advances 5, no. 79 (2015): 64806–13. http://dx.doi.org/10.1039/c5ra12217a.

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Heath, M. J. "Measurement of 'free' gold in patients receiving disodium aurothiomalate and the association of high free to total gold levels with toxicity." Annals of the Rheumatic Diseases 47, no. 1 (January 1, 1988): 18–21. http://dx.doi.org/10.1136/ard.47.1.18.

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Burkitt, Sean, Mana Mehraein, Ramunas K. Stanciauskas, Jos Campbell, Scott Fraser, and Cristina Zavaleta. "Label-Free Visualization and Tracking of Gold Nanoparticles in Vasculature Using Multiphoton Luminescence." Nanomaterials 10, no. 11 (November 12, 2020): 2239. http://dx.doi.org/10.3390/nano10112239.

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Анотація:

Gold nanoparticles continue to generate interest for use in several biomedical applications. Recently, researchers have been focusing on exploiting their dual diagnostic/therapeutic theranostic capabilities. Before clinical translation can occur, regulatory agencies will require a greater understanding of their biodistribution and safety profiles post administration. Previously, the real-time identification and tracking of gold nanoparticles in free-flowing vasculature had not been possible without extrinsic labels such as fluorophores. Here, we present a label-free imaging approach to examine gold nanoparticle (AuNP) activity within the vasculature by utilizing multiphoton intravital microscopy. This method employs a commercially available multiphoton microscopy system to visualize the intrinsic luminescent signal produced by a multiphoton absorption-induced luminescence effect observed in single gold nanoparticles at frame rates necessary for capturing real-time blood flow. This is the first demonstration of visualizing unlabeled gold nanoparticles in an unperturbed vascular environment with frame rates fast enough to achieve particle tracking. Nanoparticle blood concentration curves were also evaluated by the tracking of gold nanoparticle flow in vasculature and verified against known pre-injection concentrations. Half-lives of these gold nanoparticle injections ranged between 67 and 140 s. This label-free imaging approach could provide important structural and functional information in real time to aid in the development and effective analysis of new metallic nanoparticles for various clinical applications in an unperturbed environment, while providing further insight into their complex uptake and clearance pathways.

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Zhang, Yan, Meng Li, Haiyun Liu, Shenguang Ge, and Jinghua Yu. "Label-free colorimetric logic gates based on free gold nanoparticles and the coordination strategy between cytosine and silver ions." New Journal of Chemistry 40, no. 6 (2016): 5516–22. http://dx.doi.org/10.1039/c5nj03471j.

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Southam, G., W. S. Fyfe, and T. J. Beveridge. "Immobilization of free ionic gold and L-asparagine-complexed ionic gold by Sporosarcina ureae: The importance of organo-gold complexes in gold mobility." Mining, Metallurgy & Exploration 17, no. 2 (May 2000): 129–32. http://dx.doi.org/10.1007/bf03402840.

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