Journal articles: 'Monovalent gold'

1

Lee, Han Myoung, Seung Kyu Min, Eun Cheol Lee, Jung-Hyun Min, Srinivas Odde, and Kwang S. Kim. "Hydrated copper and gold monovalent cations:Ab initiostudy." Journal of Chemical Physics 122, no. 6 (2005): 064314. http://dx.doi.org/10.1063/1.1849134.

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2

Gillet, C., and F. Liners. "Changes in distribution of short pectic polysaccharides induced by monovalent ions in the Nitella cell wall." Canadian Journal of Botany 74, no. 1 (1996): 26–30. http://dx.doi.org/10.1139/b96-004.

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Nitella cell walls exhibit a major loss of pectin when the adsorbed bivalent ions are exchanged for monovalents. 2F4 monoclonal antibody, which recognizes a conformational epitope of homogalacturonic acid induced by calcium ions, was complexed to colloidal gold and used to localize, by means of the electron microscope, the wall regions from which the leakage occurred. Comparison of the labelling between nonpretreated cell walls and NaCl or LiCl pretreated ones, with or without incubation in CDTA or in NaOH, reveals that monovalent ions induce the solubilization of a pectic fraction rich in nonesterified galacturonic acids from the primary wall. Our results also indicate that in the secondary wall of Nitella, the pectic polysaccharides could be closely joined by covalent crosslinking. Keywords: pectin, gold labelling, monoclonal antibody, ionic exchange, Nitella.

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3

Kaulen, C., and U. Simon. "Ion specific effects on the immobilisation of charged gold nanoparticles on metal surfaces." RSC Advances 8, no. 3 (2018): 1717–24. http://dx.doi.org/10.1039/c7ra10374c.

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4

Tereshatov, Evgeny E., Miroslava Semelová, Kateřina Čubová, et al. "Valence states of cyclotron-produced thallium." New Journal of Chemistry 45, no. 7 (2021): 3377–81. http://dx.doi.org/10.1039/d0nj05198e.

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5

Thorpe, J. R. "A novel methodology for double protein A-gold immunolabeling utilizing the monovalent fragment of protein A." Journal of Histochemistry & Cytochemistry 40, no. 3 (1992): 435–41. http://dx.doi.org/10.1177/40.3.1552181.

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A method for sequential protein A-gold immunolabeling is described whereby the binding of second gold probe to the first antibody-protein A-gold complex is reduced to acceptably minimal levels. Immunolabeling of thin sections of embedded pituitary tissue was used as a model system. After an initial immunolabeling for prolactin, sections were incubated in normal serum (rabbit) followed by a monovalent fragment of protein A. These latter two incubations reduced artifactual second gold probe label over prolactin-labeled secretory granules to minimal levels (much less than 1 particle per granule) when sections were subsequently immunolabeled with normal serum. The combination of normal serum and protein A fragment incubations saturates IgG and protein A binding sites on the first antibody-gold probe complex. The latter is thereafter unable to bind further IgG (and thus gold probe) because of the monovalent nature of the protein A fragment. It is suggested that this methodology may be extended to multiple immunolabeling procedures for electron microscopy. In addition, when used before single labeling this method may be an effective way to minimize nonspecific IgG binding in cases where the tissue or antibody under study may be a problem.

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Senftle, F. E., and D. B. Wright. "Synthesis of Au2S and Au2S3 Using H2S, Short-Chain and Ring-Structured Sulfur as Sulfur Sources." Zeitschrift für Naturforschung B 41, no. 9 (1986): 1081–84. http://dx.doi.org/10.1515/znb-1986-0904.

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Abstract To determine which of the two known gold sulfides (containing either mono- or trivalent gold) are formed by reacting trivalent gold with differnt allotropes of sulfur, experiments were made using three different sources of sulfur. When trivalent gold in the form of Au2(SO4)3 in concentrated acid is reacted with electrolytically formed short-chain sulfur, monovalent gold sulfide (Au2S) is formed. If hydrogen sulfide gas reacts with the same solution, trivalent gold sulfide (Au2S3) is produced. Alternatively, if ordinary a-sulfur (ring structure) is used, a 50/50 mixture of Au2S and Au2S3 is formed. The synthesis procedure for the two gold sulfides is substantially simpler than previously reported methods of preparation

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7

Kitahara, Ginga, Akira Yoshiasa, Makoto Tokuda, et al. "Crystal structure, XANES and charge distribution investigation of krennerite and sylvanite: analysis of Au—Te and Te—Te bonds in Au_1–xAg_xTe₂ group minerals." Acta Crystallographica Section B Structural Science, Crystal Engineering and Materials 78, no. 2 (2022): 117–32. http://dx.doi.org/10.1107/s2052520622000804.

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The structure refinement and XANES study of two gold–silver–tellurides [Au1+x Ag x Te2, krennerite (x = 0.11–0.13) and sylvanite (x = 0.29–0.31)] are presented and the structures are compared with the prototype structure of calaverite (x = 0.08–0.10). Whereas the latter is well known for being incommensurately modulated at ambient conditions, neither krennerite nor sylvanite present any modulation. This is attributed to the presence of relatively strong Te—Te bonds (bond distances < 2.9 Å) in the two minerals, which are absent in calaverite (bond distances > 3.2 Å). In both tellurides, trivalent gold occurs in slightly distorted square planar coordination, whereas monovalent gold, partly substituted by monovalent silver, presents a 2+2+2 coordination, corresponding to distorted rhombic bipyramids. The differentiation between bonding and non-bonding contacts is obtained by computation of the Effective Coordination Number (ECoN). The CHARge DIstribution (CHARDI) analysis is satisfactory for both tellurides but suggests that the Te—Te bond in the [Te3]2− anion is not entirely homopolar. Both tellurides can therefore be described as Madelung-type compounds, despite the presence of Te–Te in both structures.

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Abdurazova, Perizat, Malik Sataev, Gulmira Kenzhibayeva, Shayzada Koshkarbayeva, Kalamkas Amanbayeva, and Yerkebulan Raiymbekov. "Photochemical production of gold films on the surface of fabric materials." Polish Journal of Chemical Technology 22, no. 4 (2020): 28–30. http://dx.doi.org/10.2478/pjct-2020-0035.

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AbstractA technology for producing gold films on the surface of fabric materials has been developed, which provides for preliminary wetting of the fabric product with aqueous solutions of gold (III) chloride. In this case, a sorption layer of gold chloride is formed on the surface of fabric materials. Then, when drying these products under sunlight, physicochemical and photochemical processes occur, leading initially to the formation of monovalent gold chlorides, which, having semiconductor properties, provide the release of elemental gold. After washing of by-products on the surface of the material remains an ultra-thin film of gold, which has a sufficiently strong grip on the base. Since the proposed technology does not require special equipment it can be used to apply functional films of gold on various products of technical, household and medical purposes.

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9

Perevalova, �. G., T. V. Baukova, M. M. Sazonenko, and K. I. Grandberg. "Reaction of monovalent gold complex salts with ferrocene thio derivatives." Bulletin of the Academy of Sciences of the USSR Division of Chemical Science 34, no. 8 (1985): 1722–26. http://dx.doi.org/10.1007/bf00948525.

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10

Nieves, D. J., N. S. Azmi, R. Xu, R. Lévy, E. A. Yates, and D. G. Fernig. "Monovalent maleimide functionalization of gold nanoparticles via copper-free click chemistry." Chem. Commun. 50, no. 86 (2014): 13157–60. http://dx.doi.org/10.1039/c4cc05909c.

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A single maleimide was installed onto the self-assembled monolayer of gold nanoparticles by copper-free click chemistry. Simple covalent biofunctionalisation is demonstrated by coupling fibroblast growth factor 2 and an oligosaccharide in a 1 : 1 stoichiometry by thiol-Michael addition.

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11

Schönekerl, Stefan, and Jörg Acker. "The Role of the Molecular Hydrogen Formation in the Process of Metal-Ion Reduction on Multicrystalline Silicon in a Hydrofluoric Acid Matrix." Nanomaterials 11, no. 4 (2021): 982. http://dx.doi.org/10.3390/nano11040982.

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Metal deposition on silicon in hydrofluoric acid (HF) solutions is a well-established process for the surface patterning of silicon. The reactions behind this process, especially the formation or the absence of molecular hydrogen (H2), are controversially discussed in the literature. In this study, several batch experiments with Ag+, Cu2+, AuCl4− and PtCl62− in HF matrix and multicrystalline silicon were performed. The stoichiometric amounts of the metal depositions, the silicon dissolution and the molecular hydrogen formation were determined analytically. Based on these data and theoretical considerations of the valence transfer, four reasons for the formation of H2 could be identified. First, H2 is generated in a consecutive reaction after a monovalent hole transfer (h+) to a Si–Si bond. Second, H2 is produced due to a monovalent hole transfer to the Si–H bonds. Third, H2 occurs if Si–Si back bonds of the hydrogen-terminated silicon are attacked by Cu2+ reduction resulting in the intermediate species HSiF3, which is further degraded to H2 and SiF62−. The fourth H2-forming reaction reduces oxonium ions (H3O+) on the silver/, copper/ and gold/silicon contacts via monovalent hole transfer to silicon. In the case of (cumulative) even-numbered valence transfers to silicon, no H2 is produced. The formation of H2 also fails to appear if the equilibrium potential of the 2H3O+/H2 half-cell does not reach the energetic level of the valence bands of the bulk or hydrogen-terminated silicon. Non-hydrogen-forming reactions in silver, copper and gold deposition always occur with at least one H2-forming process. The PtCl62− reduction to Pt proceeds exclusively via even-numbered valence transfers to silicon. This also applies to the reaction of H3O+ at the platinum/silicon contact. Consequently, no H2 is formed during platinum deposition.

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12

Smith, R. M., R. I. Goldberg, and L. Jarett. "Preparation and characterization of a colloidal gold-insulin complex with binding and biological activities identical to native insulin." Journal of Histochemistry & Cytochemistry 36, no. 4 (1988): 359–65. http://dx.doi.org/10.1177/36.4.3279110.

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We studied the binding and biological activities of gold-insulin complexes to develop a complex with properties identical to native insulin. Stabilizing amounts of insulin absorbed to 5-, 10-, or 15-nm gold particles resulted in complexes with 40-327 insulin molecules per gold particle and 4-111 times the biological activity of unlabeled insulin, based on the molar concentration of gold complex. These data suggested that these complexes behaved as multivalent ligands. Gold-insulin complexes were prepared with 5% of the stabilizing insulin concentration and were stabilized with bovine serum albumin. This resulted in a complex with 5-7 insulin molecules per 10-nm gold particle, which stimulated glucose oxidation in rat adipocytes and competed with [125I]-insulin for binding to the insulin receptor identically to unlabeled insulin on an equimolar basis. The organization and distribution of insulin receptors occupied by this monovalent-behaving gold-insulin complex were virtually identical to previous observations using monomeric ferritin-insulin. Since multivalent ligands may affect receptor binding, re-distribution, and intracellular processing, the use of electron-dense probes that resemble the unlabeled ligand in biological and binding properties is appropriate when studying receptor dynamics of in vivo or in vitro biological systems. The gold-insulin complex developed in this study should serve this function.

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13

Ibáñez, María M., Susana K. Checa, and Fernando C. Soncini. "A Single Serine Residue Determines Selectivity to Monovalent Metal Ions in Metalloregulators of the MerR Family." Journal of Bacteriology 197, no. 9 (2015): 1606–13. http://dx.doi.org/10.1128/jb.02565-14.

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ABSTRACTMerR metalloregulators alleviate toxicity caused by an excess of metal ions, such as copper, zinc, mercury, lead, cadmium, silver, or gold, by triggering the expression of specific efflux or detoxification systems upon metal detection. The sensor protein binds the inducer metal ion by using two conserved cysteine residues at the C-terminal metal-binding loop (MBL). Divalent metal ion sensors, such as MerR and ZntR, require a third cysteine residue, located at the beginning of the dimerization (α5) helix, for metal coordination, while monovalent metal ion sensors, such as CueR and GolS, have a serine residue at this position. This serine residue was proposed to provide hydrophobic and steric restrictions to privilege the binding of monovalent metal ions. Here we show that the presence of alanine at this position does not modify the activation pattern of monovalent metal sensors. In contrast, GolS or CueR mutant sensors with a substitution of cysteine for the serine residue respond to monovalent metal ions or Hg(II) with high sensitivities. Furthermore, in a mutant deleted of the Zn(II) exporter ZntA, they also trigger the expression of their target genes in response to either Zn(II), Cd(II), Pb(II), or Co(II).IMPORTANCESpecificity in a stressor's recognition is essential for mounting an appropriate response. MerR metalloregulators trigger the expression of specific resistance systems upon detection of heavy metal ions. Two groups of these metalloregulators can be distinguished, recognizing either +1 or +2 metal ions, depending on the presence of a conserved serine in the former or a cysteine in the latter. Here we demonstrate that the serine residue in monovalent metal ion sensors excludes divalent metal ion detection, as its replacement by cysteine renders a pan-metal ion sensor. Our results indicate that the spectrum of signals detected by these sensors is determined not only by the metal-binding ligand availability but also by the metal-binding cavity flexibility.

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14

Yao, Guangbao, Hao Pei, Jiang Li, et al. "Clicking DNA to gold nanoparticles: poly-adenine-mediated formation of monovalent DNA-gold nanoparticle conjugates with nearly quantitative yield." NPG Asia Materials 7, no. 1 (2015): e159-e159. http://dx.doi.org/10.1038/am.2014.131.

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Vanni, Costanza, Anne Bodlenner, Marco Marradi та ін. "Hybrid Multivalent Jack Bean α-Mannosidase Inhibitors: The First Example of Gold Nanoparticles Decorated with Deoxynojirimycin Inhitopes". Molecules 26, № 19 (2021): 5864. http://dx.doi.org/10.3390/molecules26195864.

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Among carbohydrate-processing enzymes, Jack bean α-mannosidase (JBα-man) is the glycosidase with the best responsiveness to the multivalent presentation of iminosugar inhitopes. We report, in this work, the preparation of water dispersible gold nanoparticles simultaneously coated with the iminosugar deoxynojirimycin (DNJ) inhitope and simple monosaccharides (β-d-gluco- or α-d-mannosides). The display of DNJ at the gold surface has been modulated (i) by using an amphiphilic linker longer than the aliphatic chain used for the monosaccharides and (ii) by presenting the inhitope, not only in monomeric form, but also in a trimeric fashion through combination of a dendron approach with glyconanotechnology. The latter strategy resulted in a strong enhancement of the inhibitory activity towards JBα-man, with a Ki in the nanomolar range (Ki = 84 nM), i.e., more than three orders of magnitude higher than the monovalent reference compound.

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16

Dey, G. R., A. K. El Omar, J. A. Jacob, M. Mostafavi, and J. Belloni. "Mechanism of Trivalent Gold Reduction and Reactivity of Transient Divalent and Monovalent Gold Ions Studied by Gamma and Pulse Radiolysis." Journal of Physical Chemistry A 115, no. 4 (2011): 383–91. http://dx.doi.org/10.1021/jp1096597.

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17

Wickleder, Mathias S., and Oliver Büchner. "The Gold Sulfates MAu(S04)2 (M = Na, K, Rb)." Zeitschrift für Naturforschung B 56, no. 12 (2001): 1340–43. http://dx.doi.org/10.1515/znb-2001-1215.

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AbstractThe evaporation of a solution of Au(OH)3 and Na2So4 in conc. sulfuric acid led to yellow single crystals of NaAu(SO4)2 (monoclinic, P21/n, Z = 2, a = 469.1, b = 845.9, c = 831.2 pm, β = 95.7°). Analogous procedures with K2SO4 or Rb2SO4 instead of Na2SO4 yielded single crystals of KAu(SO4)2 (monoclinic, C2/c, Z = 4, a = 1109.8, b = 724.2, c = 941.1 pm, β = 118.4°) and RbAu(S04)2, respectively, (triclinic, P1̄, Z = 1, a = 423.6, b = 497.5, c = 889.0 pm, a = 76.4°, β = 88.4°, γ = 73.5°). Although the crystal structures of the three sulfates are not isotypic they show similar structural features: The gold atoms are coordinated by four oxygen atoms in a square planar manner. These oxygen atoms belong to four SO42- ions which link the [AUO4] units to infinite chains according to 1∞[Au(SO4)4/ 2]- . These chains are connected via the monovalent cations which show coordination numbers of 6 (Na+), 10 (K+) and 12 (Rb+), respectively.

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18

Cheng, Yangjian, Zhibin Ke, Xiaojing Bian, et al. "Selective Mineralization and Recovery of Au(III) from Multi-Ionic Aqueous Systems by Bacillus licheniformis FZUL-63." Minerals 9, no. 7 (2019): 392. http://dx.doi.org/10.3390/min9070392.

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The recovery of precious metals is a project with both economic and environmental significance. In this paper, how to use bacterial mineralization to selectively recover gold from multi-ionic aqueous systems is presented. The Bacillus licheniformis FZUL-63, isolated from a landscape lake in Fuzhou University, was shown to selectively mineralize and precipitate gold from coexisting ions in aqueous solution. The removal of Au(III) almost happened in the first hour. Scanning electron microscope with X-ray energy dispersive spectroscopy (SEM/EDS-mapping) results and fourier transform infrared spectroscopy (FTIR) data show that the amino, carboxyl, and phosphate groups on the surface of the bacteria are related to the adsorption of gold ions. X-ray photoelectron spectroscopy (XPS) results implied that Au(III) ions were reduced to those that were monovalent, and the Au(I) was then adsorbed on the bacterial surface at the beginning stage (in the first hour). X-ray diffraction (XRD) results showed that the gold biomineralization began about 10 h after the interaction between Au(III) ions and bacteria. Au(III) mineralization has rarely been influenced by other co-existing metal ions. Transmission electron microscope (TEM) analysis shows that the gold nanoparticles have a polyhedral structure with a particle size of ~20 nm. The Bacillus licheniformis FZUL-63 could selectively mineralize and recover 478 mg/g (dry biomass) gold from aqua regia-based metal wastewater through four cycles. This could be of great potential in practical applications.

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Mateos, Helena, Rosaria A. Picca, Antonia Mallardi, et al. "Effect of the Surface Chemical Composition and of Added Metal Cation Concentration on the Stability of Metal Nanoparticles Synthesized by Pulsed Laser Ablation in Water." Applied Sciences 10, no. 12 (2020): 4169. http://dx.doi.org/10.3390/app10124169.

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Metal nanoparticles (NPs) made of gold, silver, and platinum have been synthesized by means of pulsed laser ablation in liquid aqueous solution. Independently from the metal nature, all NPs have an average diameter of 10 ± 5 nm. The ζ-potential values are: −62 ± 7 mV for gold, −44 ± 2 mV for silver and −58 ± 3 for platinum. XPS analysis demonstrates the absence of metal oxides in the case of gold and silver NPs. In the case of platinum NPs, 22% of the particle surface is ascribed to platinum oxidized species. This points to a marginal role of the metal oxides in building the negative charge that stabilizes these colloidal suspensions. The investigation of the colloidal stability of gold NPs in the presence of metal cations shows these NPs can be destabilized by trace amounts of selected metal ions. The case of Ag+ is paradigmatic since it is able to reduce the NP ζ-potential and to induce coagulation at concentrations as low as 3 μM, while in the case of K+ the critical coagulation concentration is around 8 mM. It is proposed that such a huge difference in destabilization power between monovalent cations can be accounted for by the difference in the reduction potential.

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20

Liao, Yi-Hung, Chih-Hsiang Lin, Ching-Ya Cheng, Wai Cheng (Christine) Wong, Jz-Yuan Juo, and Chia-Lung Hsieh. "Monovalent Labeling of Gold Nanoprobes for Ultrafast Tracking of Single-Membrane Molecules in Live Cells." Biophysical Journal 118, no. 3 (2020): 233a. http://dx.doi.org/10.1016/j.bpj.2019.11.1378.

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21

Choowongkomon, Kiattawee, Janeyuth Chaisakul, Supaphorn Seetaha, et al. "Development of a Biosensor to Detect Venom of Malayan Krait (Bungarus candidus)." Toxins 16, no. 1 (2024): 56. http://dx.doi.org/10.3390/toxins16010056.

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Malayan krait (Bungarus candidus) envenoming is a cause of significant morbidity and mortality in many Southeast Asian countries. If intubation and specific antivenom administration are delayed, the most significant life-threatening outcome may be the inhibition of neuromuscular transmission and subsequent respiratory failure. It is recommended that krait-envenomed victims without indications of neurotoxicity, e.g., skeletal muscle weakness or ptosis, immediately receive 10 vials of antivenom. However, the administration of excess antivenom may lead to hypersensitivity or serum sickness. Therefore, monitoring venom concentrations in patients could be used as an indicator for snake antivenom treatment. In this study, we aimed to develop a screen-printed gold electrode (SPGE) biosensor to detect B. candidus venom in experimentally envenomed rats. The gold electrodes were coated with monovalent Malayan krait IgG antivenom and used as venom detection biosensors. Electrochemical impedance spectrometry (EIS) and square wave voltammetry (SWV) measurements were performed to detect the electrical characterization between B. candidus venom and monovalent IgG antivenom in the biosensor. The EIS measurements showed increases in charge transfer resistance (Rct) following IgG immobilization and incubation with B. candidus venom solution (0.1–0.4 mg/mL); thus, the antibody was immobilized on the electrode surface and venom was successfully detected. The lowest current signal was detected by SWV measurement in rat plasma collected 30 min following B. candidus experimental envenoming, indicating the highest level of venom concentration in blood circulation (4.3 ± 0.7 µg/mL). The present study demonstrates the ability of the SPGE biosensor to detect B. candidus venom in plasma from experimentally envenomed rats. The technology obtained in this work may be developed as a detection tool for use along with the standard treatment of Malayan krait envenoming.

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Stein, Benjamin, David Zopes, Madlen Schmudde, et al. "Kinetics of aggregation and growth processes of PEG-stabilised mono- and multivalent gold nanoparticles in highly concentrated halide solutions." Faraday Discussions 181 (2015): 85–102. http://dx.doi.org/10.1039/c5fd00024f.

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5–6 nm gold nanoparticles were prepared by hydrolytic decomposition of [NMe4][Au(CF3)2] and functionalized in situ with mono- and multivalent thiolated PEG ligands. Time-dependent changes of the nanoparticles were monitored in aqueous NaCl, NaBr, and NaI solutions by UV-Vis spectroscopy, TEM, and HRTEM. The purely sterically protected particles are stable in ≤1 M NaCl and NaBr solutions, regardless of the valence of the ligands. At higher concentrations (≥2 M), the monovalent stabilized particles show minor reaction limited colloidal aggregation. In NaBr but not in NaCl solutions a minor Ostwald ripening also occurs. The divalent stabilized particles remain colloidally stable in both halide solutions, even if the temperature is raised or the concentration is increased above 2 M. In ≤1 M aqueous NaI solutions the particles remain stable. Above, the monovalent stabilized particles undergo an oxidative reaction, resulting in a time-dependent shift and broadening of the absorbance spectrum. Finally, this process slows down while the width of the spectra slightly narrows. The kinetics of this process can be described by a two-step sigmoidal process, comprising a slow induction period where active species are formed, followed by a fast growth and aggregation process. The increasing concentration of fused structures from the aggregates during this process results in a narrowing of the size distributions. The divalent stabilized particles show only some minor broadening and a slight shift of the absorbance spectra in ≤3 M NaI solutions. These observations confirm the excellent stability of the multivalent stabilized particles from this chloride-free particle synthesis.

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van Deurs, B., T. I. Tønnessen, O. W. Petersen, K. Sandvig, and S. Olsnes. "Routing of internalized ricin and ricin conjugates to the Golgi complex." Journal of Cell Biology 102, no. 1 (1986): 37–47. http://dx.doi.org/10.1083/jcb.102.1.37.

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Receptor-mediated endocytosis and intracellular routing of native ricin, and of ricin conjugated to colloidal gold (Ri-Au) and to horseradish peroxidase (Ri-HRP), have been studied in cultured MCF-7 and Vero cells by electron microscopical techniques including serial section analysis. Both native ricin, as demonstrated by immunoperoxidase cytochemistry, and the ricin conjugates were internalized via a common coated pit-coated vesicle pathway to reach vacuolar and tubulo-vesicular portions of the endosomal system. In addition, native ricin and a purified monovalent fraction of Ri-HRP reached distinct Golgi cisterns, whereas Ri-Au and polyvalent Ri-HRP did not. The results delineate intracellular routing of native ricin and compare it with the routing of different ricin conjugates. Moreover, our study shows that conjugates of a particular ligand (ricin) and various probes (e.g., gold and peroxidase), may be handled differently by cells. Sorting apparently takes place in the endosomal system, allowing some but not other molecules to reach Golgi elements. This sorting seems to depend on the valency of the ricin conjugate.

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Ma, Lingzhi, Feng Li, Ti Fang, Jianting Zhang, and Qiangbin Wang. "Controlled Self-Assembly of Proteins into Discrete Nanoarchitectures Templated by Gold Nanoparticles via Monovalent Interfacial Engineering." ACS Applied Materials & Interfaces 7, no. 20 (2015): 11024–31. http://dx.doi.org/10.1021/acsami.5b02823.

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Radomskiy, S. M., and V. I. Radomskaya. "Surface structure of Amur region high grade native gold." Earth sciences and subsoil use 44, no. 1 (2021): 39–47. http://dx.doi.org/10.21285/2686-9993-2021-44-1-39-47.

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The purpose of the research is to study the surface structure of high grade gold. The subject of research is gold ore fields in the Amur region. The object of the study is samples of native high grade gold grains from these fields. The study uses the methods of thermodynamics and X-ray electron microscopy. The study results in revealing a multilayer structure of the surface of high grade minerals of the Amur region native gold with the following levels: a boundary layer with zero oxidation degree Au0 in the form of yellow metallic gold; an oxide layer with the oxidation degree Au+1 in the form of purple Au2O; an oxide layer with the oxidation degree Au+3 in the form of a yellow-brown Au2O3; a hydrated oxide layer with the oxidation degree Au+3 in the form of a red-yellow-brown Au(OH)3. The methods of electron microscopy have allowed to identify external surface structures – dense oxide layers of the form of Au2O3 and loose hydrated layers of the form of Au(OH)3, whereas the inner layers of metallic and monovalent gold are not visible. Important thermodynamic characteristics of the presented levels are the values of standard oxidation-reduction potentials (E°), which determine their physicochemical properties: for metallic gold E° = +1.68 V; for the oxide layer with the oxidation degree Au+1 in the form of Au2O – E° = +0.32 V; for the oxide layer with the oxidation degree Au+3 in the form of Au2O3 – E° = +1.36 V; for the hydrated oxide layer with the oxidation degree Au+3 in the form of Au(OH)3 – E° = +0.7 V. The results of the conducted studies indicate that the surface structure has several layers that lower the oxidation-reduction potential, which explains the generation and formation of migratory forms of gold in humid hypergene conditions of natural environment.

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Liao, Yi-Hung, Chih-Hsiang Lin, Ching-Ya Cheng, Wai Cheng Wong, Jz-Yuan Juo, and Chia-Lung Hsieh. "Monovalent and Oriented Labeling of Gold Nanoprobes for the High-Resolution Tracking of a Single-Membrane Molecule." ACS Nano 13, no. 10 (2019): 10918–28. http://dx.doi.org/10.1021/acsnano.9b01176.

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Huang, Chao, Chun-Li Hu, Xiang Xu, Bing-Ping Yang, and Jiang-Gao Mao. "Explorations of a Series of Second Order Nonlinear Optical Materials Based on Monovalent Metal Gold(III) Iodates." Inorganic Chemistry 52, no. 19 (2013): 11551–62. http://dx.doi.org/10.1021/ic401891f.

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28

DYADCHENKO, V. P., K. I. GRANDBERG, O. N. KALININA, et al. "ChemInform Abstract: Oxidative Addition Reaction of Disulfides, e.g. (II), with Organometallic Derivatives of Monovalent Gold, e.g. (I), (VI)." ChemInform 22, no. 11 (2010): no. http://dx.doi.org/10.1002/chin.199111279.

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Süzer, Ş., N. Ertaş, S. Kumser, and O. Y. Ataman. "X-ray Photoelectron Spectroscopic Characterization of Au Collected with Atom Trapping on Silica for Atomic Absorption Spectrometry." Applied Spectroscopy 51, no. 10 (1997): 1537–39. http://dx.doi.org/10.1366/0003702971939064.

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The nature of analyte species collected on a cooled silica tube for atom-trapping atomic absorption spectrometric determination was investigated with the use of X-ray photoelctron spectroscopy (XPS). An XPS spectrum of gold deposited on atom-trapping silica tubes reveals a Au 4f7/2 peak with a binding energy of 84.8 (±0.2) eV, which falls in the middle of the binding energies corresponding to zerovalent Au(0) at 84.0 eV and that of monovalent Au(I) at 85.2 eV. The corresponding energy for Au vapor deposited on silica is also 84.8 eV. Deposition of AuCl4- solution on silica results in two different Au 4f7/2 peaks with binding energies of 84.8 and 87.3 eV corresponding, respectively, to Au(0) and Au(III). Deposition of the same AuCl4- solution on platinum metal again gives two peaks, this time at 84.4 and 87.0 eV energies corresponding again to Au(0) and Au(III). Combining all these data, we conclude that gold is trapped on atom-trapping silica surface as zerovalent Au(0) with a 0.8-eV matrix shift with respect to the metal surface. A similar 0.6-eV shift is also observed between the binding energy of 4f7/2Hg22+ measured in Hg2(NO3)2·2H2O powder and that deposited on silica.

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Huang, Chao, Chun-Li Hu, Xiang Xu, Bing-Ping Yang, and Jiang-Gao Mao. "ChemInform Abstract: Explorations of a Series of Second Order Nonlinear Optical Materials Based on Monovalent Metal Gold(III) Iodates." ChemInform 44, no. 49 (2013): no. http://dx.doi.org/10.1002/chin.201349003.

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Ukkonen, P., V. Lewis, M. Marsh, A. Helenius, and I. Mellman. "Transport of macrophage Fc receptors and Fc receptor-bound ligands to lysosomes." Journal of Experimental Medicine 163, no. 4 (1986): 952–71. http://dx.doi.org/10.1084/jem.163.4.952.

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Mouse macrophage Fc receptors specific for IgG1/IgG2b mediate the binding and pinocytic uptake of soluble IgG-containing antibody-antigen complexes. Internalization of these multivalent IgG complexes is accompanied not only by the intracellular degradation of the ligand, but also by a net decrease in the number of plasma membrane Fc receptors and an accelerated rate of receptor turnover. In contrast, internalized receptors bound to a monovalent ligand, the high affinity Fab fragment of the antireceptor mAb 2.4G2, escape degradation by rapidly recycling to the cell surface. In this paper, we have characterized the intracellular pathway involved in the endocytosis and transport of Fc receptors in the J774 macrophage cell line. The results show that the uptake of multivalent ligands follows the normal pathway of receptor-mediated endocytosis: internalization in clathrin-coated pits and coated vesicles, delivery to endosomes, and finally to acid hydrolase-rich lysosomes. Immunoprecipitation of radiolabeled receptor from Percoll density gradients showed that endocytosis of the IgG complexes also results in the concomitant transport of the receptor to lysosomes. Although uptake of the monovalent Fab fragment had no detectable effect on intracellular receptor distribution, preparations of 2.4G2 Fab rendered multivalent by adsorption to colloidal gold were as effective as the IgG complexes at causing lysosomal accumulation of internalized receptors. Thus, it is likely that the down-regulation and degradation of Fc receptors which occurs during the endocytosis of antibody-antigen complexes is due to the transport of internalized receptors to lysosomes. Moreover, the ability of certain Fc receptor-bound ligands to interfere with receptor recycling and trigger lysosomal transport seems to depend on ligand valency rather than on the presence or absence of Fc domains on intact IgG molecules.

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Ježková, Martina, Petr Jelínek, Ivana Šloufová, and Miroslav Šoóš. "Size, shape and surface structure of gold snowflake-like particles tailored by the addition of monovalent and divalent inorganic salts." Surfaces and Interfaces 25 (August 2021): 101160. http://dx.doi.org/10.1016/j.surfin.2021.101160.

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Louie, Stacey M., Eleanor R. Spielman-Sun, Mitchell J. Small, Robert D. Tilton, and Gregory V. Lowry. "Correlation of the Physicochemical Properties of Natural Organic Matter Samples from Different Sources to Their Effects on Gold Nanoparticle Aggregation in Monovalent Electrolyte." Environmental Science & Technology 49, no. 4 (2015): 2188–98. http://dx.doi.org/10.1021/es505003d.

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Li, Zhiguo, Tianxing Niu, Zhenjiang Zhang, Guiying Feng, and Shuping Bi. "Effect of monovalent cations (Li+, Na+, K+, Cs+) on self-assembly of thiol-modified double-stranded and single-stranded DNA on gold electrode." Analyst 137, no. 7 (2012): 1680. http://dx.doi.org/10.1039/c2an15716k.

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Szymczyk, Anna, Marcin Drozd, Agnieszka Kamińska, et al. "Comparative Evaluation of Different Surface Coatings of Fe3O4-Based Magnetic Nano Sorbent for Applications in the Nucleic Acids Extraction." International Journal of Molecular Sciences 23, no. 16 (2022): 8860. http://dx.doi.org/10.3390/ijms23168860.

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Nucleic acid extraction and purification are crucial steps in sample preparation for multiple diagnostic procedures. Routine methodologies of DNA isolation require benchtop equipment (e.g., centrifuges) and labor-intensive steps. Magnetic nanoparticles (MNPs) as solid-phase sorbents could simplify this procedure. A wide range of surface coatings employs various molecular interactions between dsDNA and magnetic nano-sorbents. However, a reliable, comparative evaluation of their performance is complex. In this work, selected Fe3O4 modifications, i.e., polyethyleneimine, gold, silica, and graphene derivatives, were comprehensively evaluated for applications in dsDNA extraction. A family of single batch nanoparticles was compared in terms of morphology (STEM), composition (ICP-MS/MS and elemental analysis), surface coating (UV-Vis, TGA, FTIR), and MNP charge (ζ-potential). ICP-MS/MS was also used to unify MNPs concentration allowing a reliable assessment of individual coatings on DNA extraction. Moreover, studies on adsorption medium (monovalent vs. divalent ions) and extraction buffer composition were carried out. As a result, essential relationships between nanoparticle coatings and DNA adsorption efficiencies have been noticed. Fe3O4@PEI MNPs turned out to be the most efficient nano sorbents. The optimized composition of the extraction buffer (medium containing 0.1 mM EDTA) helped avoid problems with Fe3+ stripping, which improved the validity of the spectroscopic determination of DNA recovery.

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Donohue, Matthew P., Zhijun Cao, Thomas Bowen, Robert Dickinson, Ying Zhang, and Jiang Qian. "The CombE-IDMS Alternate Potency Method for H5N1 and H5N8 Cell-Based Vaccines." Vaccines 11, no. 12 (2023): 1799. http://dx.doi.org/10.3390/vaccines11121799.

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Assaying the potency of inactivated viral influenza vaccines is performed using single radial immunodiffusion, which is the globally accepted release method for potency. Under conditions of a rapidly emerging pandemic, such as the 2009 H1N1 influenza pandemic, a recognized obstacle in the delivery of vaccines to the public is the time needed for the distribution of calibrated SRID reagents (antisera and antigen standards) to vaccine manufacturers. Previously, we first described a novel streamlined MS-based assay, CombE-IDMS, which does not rely on antisera/antibodies or reference antigens, as a potential rapidly deployable alternate potency method through a comparison with SRID on adjuvanted seasonal quadrivalent vaccine cell-based (aQIVc) materials. In this report, we further demonstrate that the CombE-IDMS method can also be applied to measure the potency of pre-pandemic H5N1 and H5N8 monovalent vaccine materials, each subtype both unadjuvanted and adjuvanted, through a forced degradation study. Overall, CombE-IDMS results align with those of the gold standard SRID method on both H5N1 and H5N8 materials under conditions of thermal, pH, oxidative and freeze/thaw stress, lending further evidence for the CombE-IDMS method’s suitability as an alternate assay for potency of both seasonal and pandemic influenza vaccines.

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Pfeiffer, J. R., J. C. Seagrave, B. H. Davis, G. G. Deanin, and J. M. Oliver. "Membrane and cytoskeletal changes associated with IgE-mediated serotonin release from rat basophilic leukemia cells." Journal of Cell Biology 101, no. 6 (1985): 2145–55. http://dx.doi.org/10.1083/jcb.101.6.2145.

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Binding of antigen to IgE-receptor complexes on the surface of RBL-2H3 rat basophilic leukemia cells is the first event leading to the release of cellular serotonin, histamine, and other mediators of allergic, asthmatic, and inflammatory responses. We have used dinitrophenol-conjugated bovine serum albumin (DNP-BSA) as well as the fluorescent antigen, DNP-B-phycoerythrin, and the electron-dense antigen, DNP-BSA-gold, to investigate dynamic membrane and cytoskeletal events associated with the release of [3H]serotonin from anti-DNP-IgE-primed RBL-2H3 cells. These multivalent antigens bind rapidly to cell surface IgE-receptor complexes. Their distribution is initially uniform, but within 2 min DNP-BSA-gold is found in coated pits and is subsequently internalized. Antigen internalization occurs in the presence and absence of extracellular Ca2+. The F-actin content of the detergent-extracted cell matrices analyzed by SDS PAGE decreases during the first 10-30 s of antigen binding and then increases by 1 min to almost double the control levels. A rapid and sustained increase is also observed when total F-actin is quantified by flow cytometry after binding of rhodamine-phalloidin. The antigen-stimulated increase in F-actin coincides with (and may cause) the transformation of the cell surface from a finely microvillous to a highly folded or plicated topography. Other early membrane responses include increased cell spreading and a 2-3-fold increase in the uptake of fluorescein-dextran by fluid pinocytosis. The surface and F-actin changes show the same dependence on DNP-protein concentration as stimulated [3H]serotonin release; and both the membrane responses and the release of mediators are terminated by the addition of the non-cross-linking monovalent ligand, DNP-lysine. These data indicate that the same antigen-stimulated transduction pathway controls both the membrane/cytoskeletal and secretory events. However, the membrane and actin responses to IgE-receptor cross-linking are independent of extracellular Ca2+ and are mimicked by phorbol myristate acetate, whereas ligand-dependent mediator release depends on extracellular Ca2+ and is mimicked by the Ca2+ ionophore A23187.

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Marshall-Gradisnik, Sonya M., Peter Smith, Ekua W. Brenu, Bernd Nilius, Sandra B. Ramos, and Donald R. Staines. "Examination of Single Nucleotide Polymorphisms (SNPs) in Transient Receptor Potential (TRP) Ion Channels in Chronic Fatigue Syndrome Patients." Immunology and Immunogenetics Insights 7 (January 2015): III.S25147. http://dx.doi.org/10.4137/iii.s25147.

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Background The transient receptor potential (TRP) superfamily in humans comprises 27 cation channels with permeability to monovalent and divalent cations. These channels are widely expressed within humans on cells and tissues and have significant sensory and regulatory roles on most physiological functions. Chronic fatigue syndrome (CFS) is an unexplained disorder with multiple physiological impairments. OBJECTIVES The purpose of this study was to determine the role of TRPs in CFS. Methods The study comprised 115 CFS patients (age = 48.68 ± 1.06 years) and 90 nonfatigued controls (age = 46.48 ± 1.22 years). CFS patients were defined according to the 1994 Center for Disease Prevention and Control criteria for CFS. A total of 240 single nucleotide polymorphisms (SNPs) for 21 mammalian TRP ion channel genes ( TRPA1, TRPC1, TRPC2, TRPC3, TRPC4, TRPC6, TRPC7, TRPM1, TRPM2, TRPM3, TRPM4, TRPM5, TRPM6, TRPM7, TRPM8, TRPV1, TRPV2, TRPV3, TRPV4, TRPV5, and TRPV6) were examined via the Agena Biosciences iPLEX Gold assay. Statistical analysis was performed using the PLINK analysis software. Results Thirteen SNPs were significantly associated with CFS patients compared with the controls. Nine of these SNPs were associated with TRPM3 (rs12682832; P < 0.003, rs11142508; P < 0.004, rs1160742; P < 0.08, rs4454352; P < 0.013, rs1328153; P < 0.013, rs3763619; P < 0.014, rs7865858; P ≤ 0.021, rs1504401; P ≤ 0041, rs10115622; P ≤ 0.050), while the remainder were associated with TRPA1 (rs2383844; P ≤ 0.040, rs4738202; P ≤ 0.018) and TRPC4 (rs6650469; P ≤ 0.016, rs655207; P ≤ 0.018). Conclusion The data from this pilot study suggest an association between TRP ion channels, predominantly TRPM3 and CFS. This and other TRPs identified may contribute to the etiology and pathomechanism of CFS.

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Qin, Xuecong, Tao Zhang, Wenhua Qin, and Hongbo Zhang. "Effect of Nickel Impurities in Pyrite on Catalytic Degradation of Thiosulfate." Metals 14, no. 11 (2024): 1256. http://dx.doi.org/10.3390/met14111256.

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The effects of nickel content in nickel-bearing pyrite on photocatalytic properties, light absorption properties, and oxidative decomposition of thiosulfate were studied. The leaching experiments show that the consumption of thiosulfate in the Cu2+-ethylenediamine (en)-S2O32− system increases with an increase in nickel content in nickel-bearing pyrite. The consumption of Cu(en)22+ initially increases and then decreases with an increase in leaching time. There is a clear correlation between the change trend in its consumption and the doping amount of nickel in pyrite. The XPS results show that in the Cu2+-ethylenediamine (en)-S2O32− leaching gold system (temperature 25 °C, time 35 h, solution: 0.1 mol/L S2O32−, 5 mmol/L Cu(en)22+, 200 mL solution), the nickel of pyrite-containing nickel can be transferred to the leaching solution and becomes nickel ion. In this leaching system, Cu(II), which was originally complexed with en, is reduced to Cu(I) in a short time. The consumption of Cu(en)22+ increased rapidly in the 5 h period and then decreased gradually after 5 h. The results showed that the presence of free Ni2+ in the solution facilitated the conversion of bivalent copper ions to monovalent copper ions. Free Ni2+ ions can compete with Cu2+ ions for en ligands. When ethylenediamine complexes with Ni2+, the decomposition of Cu(en)22+ into Cu(en)+ and en occurs more rapidly. And the en, which was originally to be oxidized with Cu(en)+ to form Cu(en)22+, forms Ni(en)22+. As a result, the concentration of Cu(en)22+ continues to decrease in a short period of time.

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Meyer, D. A., and R. M. Albrecht. "The Feasibility of High Resolution, Multiple Labeling using Colloidal Particles of Similar Size but Different Shapes and Elemental Compositions." Microscopy and Microanalysis 7, S2 (2001): 1032–33. http://dx.doi.org/10.1017/s1431927600031238.

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High resolution, quantitative cell labeling analysis for electron microscopy is typically accomplished using colloidal gold (cAu) particles which have a uniform diameter such that each particle conjugates no more than one ligand with monovalent specificity, such as an Fab antibody fragment. in this way, one particle labels exactly one target molecule. The corresponding particle size which satisfies this requirement, in the case of the Fab fragment, is 3-5nm. Under these constraints, multiple labeling cannot be performed using the standard cAu technology in which particles of various diameters are used such that each size corresponds to a unique label. Particles larger than 5nm may conjugate multiple Fab fragments, and thus a single particle may lable multiple target sites. Conversely, several particles smaller than 3nm may bind to a single Fab fragment so that several particles may label a single target molecule. Recent work in our lab has focused on the development of a labeling system which maintains the advantages of the standard cAu labeling technology, namely the use of electron-dense particles with excellent secondary and backscattered electron emission properties which make them readily detectable by both TEM and SEM, while at the same time offering greater versatility by permitting multiple labeling for high resolution, quantitative analysis. This novel labeling system makes use of colloidal particles which have unique and distinctive shapes, and composed of a variety of different metals including Au, Ag, Pt, Pd, Rh, and Ru. These elements all form stable aqueous colloidal suspensions, and the particles have surface charge properties similar to those of Au, permitting the adsorption of proteins and other ligands to them by the same conjugation techniques used with cAu (fig. 1).

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Herrala, Reima, Linfan Cui, Benjamin Wilson, Kirsi Yliniemi, and Mari Lundström. "(Invited) Aqueous Electrochemical Reduction Approaches for Functionalized Surfaces." ECS Meeting Abstracts MA2024-02, no. 22 (2024): 1928. https://doi.org/10.1149/ma2024-02221928mtgabs.

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To meet the demands of the green transition and mitigate climate change there is an increasingly urgent need for a wide range of crucial raw materials. Global resource scarcity, criticality, and supply disruption due to material shortfalls or geopolitical instability is driving efforts towards an inclusive, multi-materials circular economy with the objective of providing a more sustainable future. Within the domain of metals production, recent focus has been on development of new technological approaches that maximize the recovery of valuable materials, whilst simultaneously aiming at the reduction of the associated environmental impacts. In addition, the shift towards the increased use of lower grade input materials - either because of reduced ore quality or inclusion of secondary raw materials sources as feedstocks - often means there is a broader range of impurities within metallurgical process streams. In the case of industrial hydrometallurgical base metals—Cu, Ni, Zn—production methods like leaching, precipitation, and electrochemical reduction (electrorefining/electrowinning) impurities can include valuable metals like silver, gold, or platinum at such limited concentrations that conventional methods of recovery are often not economically viable. Moreover, the nature of hydrometallurgy process solution is that it is often contain highly concentrated levels of base metal (10’s g/l) - relative to the impurity materials (ppm/ppb) - that excludes the selective extraction of the valuable metals by conventional separation steps like solvent extraction, precipitation, cementation, or ion exchange. Consequently, there exists a need for alternative methods that can efficiently remove such low-level elements from complex solutions for recirculation or re-use. Over the last decade, two related electrochemical approaches have emerged as possible ways not only for the recovery of metals at low concentrations, but also for the creation of surfaces with additional functionality. The Electrodeposition-Redox Replacement (EDRR) methodology [1] exploits the cathodic reduction of less noble metal ions to electrodeposit a solid layer on an electrode surface by application of a constant or pulsed potential or constant current. This ED process is then followed by a period when the system is allowed to relax to its open circuit potential (OCP), which results in the spontaneous redox replacement (RR) of the deposited metal layer with more noble ions from the solution. These two steps - which can also be considered as sequential electrowinning-cementation - can be tailored to salvage different metals or produce different surfaces depending on the predominating base metal and the type of impurity within solution. For example, EDRR has been utilized to recover metals including Ag (from Zn process solutions), Au (from Cl leach solutions) and Te (from metallurgical industrial waste) as well as create surfaces with catalytic, anti-corrosion and analytical applications [1]. More recently, the related Electrochemically-assisted Aqueous Reduction (EAR) method has emerged as an alternative approach to selectively recover Au from high concentration Cu chloride-based solutions[2]. In contrast to EDRR, this method uses a current or potential that is pulsed in order to reduce the copper ions in the solution proximal to the electrode from Cu(II) to Cu(I). This generated monovalent copper can then reduce the Au(III) or Au(I) present in solution due to their nobility difference. In situ studies performed with EQCM-D have allowed the influence of solution concentration changes and applied electrochemical parameters on the overall recovery process to be determined. Additionally, through the appropriate selection of the system boundaries, electrode surfaces decorated by gold nanoparticles could be created demonstrating that EAR can be used to electrochemically prepare noble metal surfaces with the potential for additional functionalities like electrochemical ethanol oxidation from complex process solutions. Overall, both EDRR and EAR offer alternative and efficient methods that allow not only for the recovery of trace levels of valuable metals from under exploited hydrometallurgical solutions, but these approaches also provide the potential to directly create materials with a range of surface functionalized materials. Furthermore, EDRR is already being exploited on an industrial scale [3] to enhance energy efficiency, improve materials circularity and process economics in a range of applications. Acknowledgments This work was supported by the Research Council of Finland project EARMetal (#339979 and #342080). The RawMatTERS Finland Infrastructure (RAMI) also funded by the Research Council of Finland and based at Aalto University is acknowledged. References [1] L. Cui, K. Yliniemi, J. Vapaavuori, M. Lundström, “Recent developments of electrodeposition-redox replacement in metal recovery and functional materials: A review” Chemical Engineering Journal 465, (2023) 142737. [2] R. Herrala, Z. Wang, J. Vapaavuori, M. Lundström, K. Yliniemi, “Recovery of Gold as Nanoparticles from Gold-Poor Au-Cu-Cl Solutions” J. Phys. Chem. C, 127 (2023) 16099–16109 [3] https://elmery.fi/

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Krayushkina, L. S., and O. G. Semenova. "Reaction of osmoregulatory system of sterlet Acipenser ruthenus Linnaeus, 1758 (Acipenseridae) on influence of hyperosmotic medium." Proceedings of the Zoological Institute RAS 323, no. 4 (2019): 506–22. http://dx.doi.org/10.31610/trudyzin/2019.323.4.506.

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Some features of response to hyperosmotic environment (artificial sea water with a salinity of 12.5–12.7 ‰ (403–409 mosm/l) were studied in the osmoregulatory system of freshwater sturgeon species from the Volga river, starlet Acipenser ruthenus Linnaeus, 1758. Morphofunctional changes were traced in certain elements of the organ complex responsible for the osmoregulatory process. 72 hours after the immature sterlet individuals (age 2+) were transferred from fresh water to the hyperosmotic medium, blood serum osmolarity becomes iso-osmotic respective to the external environment. The interrenal gland responds to saline exposure by increasing cortisol concentration in the blood serum. A high cortisol level (75.13 ± 12.96 vs. 19.29 ± 6.36 ng/ml in the control group) persists throughout the entire experimental period (7 days), which indicates that fishes are under stress. The cortisol excretion into the bloodstream is not followed by an increased activity of the transport enzyme, Na+/K+ ATPase, in homogenate of the gills and an increased Na+ concentration in chloride cells, was identified by A-gold technique. The ultrastructure of chloride cells, being the main site for the removal and sorption of monovalent ions (Na+, K+, Cl-) in fishes, does not display the characteristic of an active excretion in sterlet. Thus, cortisol does not provide a stimulating effect on increasing Na+/K+ ATPase activity, an enzyme needed to transport excess ions from the body. The thyroid gland responds by increasing the thyroxin (T4) concentration during 3–6 hours of saline exposure. In the next 114 hours, the concentration of this hormone decreases to its initial level (in the control group). The thyroxin dynamics in serum does not correlate with the dynamics of serum osmolarity. So it seems possible to conclude that no functional relationship exists between the effector “organ” (the set of numerous chloride cells of the gills epithelium) and the endocrine glands (interrenal and thyroid) controlled by the hormones of tropic pituitary cells. In sterlet dwelling in hyperosmotic medium the kidney keeps a higher Na+/K+ ATPase activity, as compared with the gills. High Na+ concentration in the urine (163.2 ± 5.3 meq/l), close to its concentration in the hyperosmotic environment, high Na+ proportion (87.1 ± 0.1%) in the total concentration of major urinary cations, low level of water sorption (50.8 ± 4.0%) in the renal tubules, high diuresis (0.58 ± 0.09, ml/hr/100 g body weight) determine high level of Na+ excretion in the urine (100.95 ± 13.21 meq/ml/hr /100 g body weight). The important role of the kidney in removing Na+ excess under hyperosmotic environment underlies the osmoconformity strategy in sterlet.

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Zhong, Chengchao, Tailei Xu, Yu Shintomi, Shintaro Tachibana, Keiji Shimoda, and Yuki Orikasa. "Cation-Anion Engineering for Conductivity Enhancement in Fluorosulfide La₂SrF₄S₂." ECS Meeting Abstracts MA2024-02, no. 48 (2024): 3403. https://doi.org/10.1149/ma2024-02483403mtgabs.

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The development of high-performance fluoride-ion (F−) conductors is essential for the practical application of all-solid-state F− batteries, which are expected to have a high energy density (5000 W·h/L). To date, the crystal structures of the F− conductors have been mainly limited to perovskite-, fluorite- and tyssonite-type fluorides. None of these fluorides has yet been found to have high conductivity and a wide potential window at room temperature, necessitating a paradigm shift in materials development. We found in fluorosulfides La2SrF4S2, the triple-fluorite layer La2SrF4 allows for a two-dimensional F− conduction, which is not found in single anion fluorides[1]. The presence of a sulphur layer widens the conduction space of the F− layer and promotes the F− conduction. In this study, we attempted to improve the F− conductivity in La2SrF4S2 by cation-anion engineering. Specifically, (i) La2SrF4+xS2-xClx, in which S2− was changed to Cl− and excess F− was introduced, and (ii) La2Sr1-xPbxF4S2, in which Sr2+ was changed to Pb2+ with 6s2 lone pair electrons, were synthesized and the change in F− conductivity were explored and explained from a crystallographic point of view. Solid-state synthesis was used for all samples. The starting materials used were La2S3, LaF3, SrF2 and LaCl3 for La2SrF4+xS2-xClx and La2S3, SrF2, PbF2 and LaF3 for La2Sr1-xPbxF4S2. The raw materials were weighed in stoichiometric ratios, formed into pellets, vacuum-sealed using a Ta container and quartz tubes, and sintered at 1000 °C for 48 h. Powder X-ray diffraction was used to identify the samples, while AC impedance method was used to measure ionic conductivity. For measurements, pellets of the synthesised powder were isostatically pressed (190 MPa), re-sintered at 1000 °C for 48 h and gold deposited on both sides. (i) The ionic conductivity of La2SrF4.1S1.9Cl0.1 at 160 °C was 6.26 × 10−6 S cm−1, which is five times higher than that of La2SrF4S2. The increase in the conductivity might attribute to the introduction of excess F− in the lattice by replacing divalent S2− with monovalent Cl−. This suggests that the use of mixed-anion compounds allows carrier control by anions, which is different from the carrier control of by cation substitution in previous F− conductors. (ii) The ionic conductivity of La2Sr0.6Pb0.4F4S2 at 160 °C was 2.56 × 10−4 S cm−1, which are both higher than those of La2SrF4S2 and La2SrF4.1S1.9Cl0.1. 19F MAS NMR showed that the number of F− in the hetero-cationic environment increased after the introduction of Pb2+, suggesting that the distorted cationic sublattice is partly responsible for the conductivity enhancement. In conclusion, using the mixed-anion compound La2SrF4S2 as a model, we found new strategies to improve F− conductivity by cation-anion engineering. [1] S. Tachibana, C. Zhong, K. Ide, H. Yamasaki, T. Tojigamori, H. Miki, T. Saito, T. Kamiyama, K. Shimoda, Y. Orikasa, Chem. Mater. 2023, 35, 4235-4242.

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Uddayasankar, Uvaraj, and Ulrich J. Krull. "Energy Transfer Assays Using Quantum Dot–Gold Nanoparticle Complexes: Optimizing Oligonucleotide Assay Configuration Using Monovalently Conjugated Quantum Dots." Langmuir 31, no. 29 (2015): 8194–204. http://dx.doi.org/10.1021/acs.langmuir.5b01932.

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Niederfellner, Gerhard J., Annika Braennstroem, Frida Lindstrom, et al. "Protein Tomography Analysis Shows That CD20 Molecules Bound by Different Type I and Type II Anti-CD20 Antibodies Are Organized in Different Protein Complexes." Blood 114, no. 22 (2009): 4782. http://dx.doi.org/10.1182/blood.v114.22.4782.4782.

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Abstract Abstract 4782 Ramos cells were labeled with Type I (Rituximab and Ocrelizumab) and Type II (B1/H299 and GA101) anti-CD20 antibodies and then fixed and stained with marker gold labeled 2ary antibodies. Protein complexes connected to marker gold were analyzed by Protein TomographyTM at SIDEC and the corresponding 3D-structures visualized (∼100 structures per antibody). Less than 5 % of the refined structures were dimeric. While most (60 – 90%) CD20 molecules were present in tetramers or even higher order defined complexes, a sizeable proportion was also engaged in large protein networks (11 -38%). For the multimeric complexes, we could clearly distinguish between extended (or open) and ring-like (or closed) conformations. Although cells had been labeled with an excess of antibody, as suggested by FACS binding curves, the antibodies bound CD20 monovalently in most refined structures. Bivalent binding was overall more prevalent with Rituximab and Ocrelizumab than with B1 and GA101 (1/3 vs 1/6 structures). The proportion of CD20 molecules present in ringlike complexes was higher for the Type II than for the Type I antibodies. In co-localization experiments, Rituximab-CD20 and GA101-CD20 complexes were also found to only partially colocalize, while a large fraction of the two antibodies were found in separate cell surface compartments. These findings suggest that the different antibodies favor different CD20 conformations that seem to be associated with different protein complexes and might form the basis for initiation of different downstream signaling processes. Disclosures: Niederfellner: Roche: Employment. Braennstroem:SIDEC: Employment. Lindstrom:SIDEC: Employment. Jansson:SIDEC: Employment. Lundin:SIDEC: Employment. Schaefer:Roche: Employment. Mundigl:Roche: Employment. Umana:Glycart: Employment, Equity Ownership, Patents & Royalties. Klein:Roche: Employment, Equity Ownership, Patents & Royalties.

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Chin, Chur. "Dissolution of the spondylosis with autoimmune arthritis of the left hip joint with bone marrow edema by colloid gold for 4 weeks: A clinical image." Journal of Clinical Images and Medical Case Reports 5, no. 12 (2024). https://doi.org/10.52768/2766-7820/3395.

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Gold salts of monovalent gold with a gold-sulfur ligand (aurothiolates) are the conventional form of gold in use for the management of Rheumatoid Arthritis (RA). Colloid gold induces the pair annihilation of the Cooper electron pair (massive or massless fermion).

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Py, Alexandre, Ange Bernardin Chambissie Kameni, Paul-Alexis Pavard, et al. "Low-temperature synthesis of mixed valence gold halide perovskites and exploration of their photoluminescence properties." Journal of Materials Chemistry C, 2025. https://doi.org/10.1039/d4tc01056f.

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Petretto, Emanuele, Quy K. Ong, Francesca Olgiati, et al. "Monovalent ion-mediated charge–charge interactions drive aggregation of surface-functionalized gold nanoparticles." Nanoscale, 2022. http://dx.doi.org/10.1039/d2nr02824g.

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Monolayer-protected metal nanoparticles are a powerful tool to investigate the behavior of matter at nanoscales. We found that electrostatic interactions can lead to the formation of metastable NP dimers at moderate ionic strenghts.

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49

Dangi, Yub Raj, John Kwame Bediako, Xiaoyu Lin, et al. "Polyethyleneimine impregnated alginate capsule as a high capacity sorbent for the recovery of monovalent and trivalent gold." Scientific Reports 11, no. 1 (2021). http://dx.doi.org/10.1038/s41598-021-97228-0.

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AbstractFor the first time, a polyethyleneimine-impregnated alginate capsule (PEIIAC) with a high adsorption capacity is developed for the recovery of monovalent and trivalent gold from an acidic solution. The strategy results in a new type of adsorbent, polyethyleneimine impregnated alginate capsule (PEIIAC) with a core–shell structure having a large number of amine groups as cationic binding site, facilitating maximum uptake of anionic auric chloride. The maximum uptake of PEIIAC was 3078 and 929 mg/g for Au (III) and Au (I), respectively, are recordable compared to other reported adsorbents to date. The as-prepared material was executed to check the sorption efficacy for Au (III) and Au (I) in the pH range of 1–12. With an increment in pH, the uptake capacity for Au (III) increased, while the uptake capacity for Au (I) decreased. The FTIR, XRD, and XPS studies revealed that the gold adsorption mechanism includes ionic interactions and reduction, wherein the amine, hydroxyl, and carboxyl groups are involved. The capsule showed a higher adsorption efficiency than other reported sorbents, making the material applicable in acidic solutions for the recovery of Au (I) and Au (III).

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50

De Giglio, Osvalda, Marilena D’Ambrosio, Valentina Spagnuolo, et al. "Legionella anisa or Legionella bozemanii? Traditional and molecular techniques as support in the environmental surveillance of a hospital water network." Environmental Monitoring and Assessment 195, no. 4 (2023). http://dx.doi.org/10.1007/s10661-023-11078-z.

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Abstract Understanding the actual distribution of different Legionella species in water networks would help prevent outbreaks. Culture investigations followed by serological agglutination tests, with poly/monovalent antisera, still represent the gold standard for isolation and identification of Legionella strains. However, also MALDI-TOF and mip-gene sequencing are currently used. This study was conducted to genetically correlate strains of Legionella non pneumophila (L-np) isolated during environmental surveillance comparing different molecular techniques. Overall, 346 water samples were collected from the water system of four pavilions located in a hospital of the Apulia Region of Italy. Strains isolated from the samples were then identified by serological tests, MALDI-TOF, and mip-gene sequencing. Overall, 24.9% of water samples were positive for Legionella, among which the majority were Legionella pneumophila (Lpn) 1 (52.3%), followed by Lpn2-15 (20.9%), L-np (17.4%), Lpn1 + Lpn2-15 (7.1%), and L-np + Lpn1 (2.3%). Initially, L-np strains were identified as L. bozemanii by monovalent antiserum, while MALDI-TOF and mip-gene sequencing assigned them to L. anisa. More cold water than hot water samples were contaminated by L. anisa (p < 0.001). PFGE, RAPD, Rep-PCR, and SAU-PCR were performed to correlate L. anisa strains. Eleven out of 14 strains identified in all four pavilions showed 100% of similarity upon PFGE analysis. RAPD, Rep-PCR, and SAU-PCR showed greater discriminative power than PFGE.

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Journal articles on the topic 'Monovalent gold'

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