Sintering-Induced Nucleation and Growth of Noble Metal Nanoparticles for Plasmonic Resonance Ceramic Color

This study demonstrates the formation of nanoparticles (NPs) from metal salts within ceramic glazes, such that the use of this colorant technology is more accessible to artisans, employs less metal content, is less environmentally harmful, and allows for the use of traditional kilns. Gold NPs have been demonstrated to possess a specific, low material loading use as a ceramic glaze colorant via plasmon resonance. Pre-synthesized gold NPs that are added to ceramic glazes have been found to significantly change in size after firing in both reductive and oxidative atmospheres, but still maintain some size relationships and color properties. Unfortunately, it is not viable for the art community to fabricate and employ gold NP systems with high precision in a studio setting; however, the use of noble metal salts or metal oxides are realistic. To that end, this work investigates spontaneous gold and silver NP synthesis by the firing-induced development of NPs from metallic salts included within the glaze materials. Glaze samples with gold and silver salts are fired in reductive and oxidative environments, yielding a range of surface plasmon coloring effects for ceramic coloring. Additionally, the use of gold NP waste (precipitated Au NPs waste) was added to wet ceramic glazes to investigate firing effects on NPs precipitate and potential use as an alternative colorant. Sintering-induced NP nucleation and growth was observed after firing in both oxidation and reduction environments, although to differing degrees. The direct noble metal salt application process eliminates the need for preliminary gold NP synthesis, thus allowing for more practical and environmentally friendly methods in creating plasmonic resonance ceramic coloring, potentially reflective of the processes employed in ancient nanoparticle glasses

A Multi-Size Study of Gold Nanoparticle Degradation and Reformation in Ceramic Glazes

Most traditional ceramic glazes employ high amounts of transition metal colorants that are toxic to the environment and can cause health issues in humans through surface leaching. Gold nanoparticles (Au-NPs) have been found to be environmentally friendly and non-toxic alternative metal colorant in ceramic glazes. The plasmon band observed with Au-NPs can result in vibrant solutions by manipulating NP size, shape, and concentration; however, the effects of traditional firing in both reductive and oxidative kilns on Au-NPs are poorly understood. Aside from ancient art processes whose mechanisms have not been fully explored, the use of Au-NPs as suspended ceramic glaze colorants remains somewhat unexplored. Au-NPs have been previously reported to diminish in size during sintering and possess significant differences in concentration with respect to reduction and oxidation firing atmospheres. As a means of studying possible degradation/renucleation processes within the glaze during firing, a systematic study introducing different diameter Au-NPs into the glaze materials was conducted with transmission electron microscopy and reflectance spectroscopy used to probe possible mechanisms which showed changes to Au-NP diameter and color intensity, making this work applicable to industry and art current practices

CMS physics technical design report : Addendum on high density QCD with heavy ions

Peer reviewe

Elucidation of Peptide Sequence Effects that Control the Activity, Size, and Function of Nanoparticles

Bio-inspired nanoparticle catalysis offers the opportunity to improve on current catalytic standards with respect to turnover efficiency, organic solvent use, and thermal activation. Unfortunately, projected energy demands will soon outweigh our fuel supplies. The task of creating multifunctional catalysts that both lower thermal activation and possess a number of functions in aqueous conditions is daunting. Similar to these needs, nature has evolved to create a wide range of highly specialized catalytic processes, which incorporate inorganic materials, take place in ambient temperatures, and in an aqueous environment. These specialized biological systems provide inspiration, but are not applicable to current needs. Exploitation of these biotic-abiotic systems could allow for green, multifunctional catalysts. In the resulting works, a peptide sequence has been isolated via phage display with affinity for Pd surfaces, that forms stable, peptide-capped nanoparticles. Substitution of residues results in the tuning of both nanocatalyst activity and nanoparticle size, such that a peptide surface-controlling effect can be noted. These characteristics can be exploited to ultimately understand the binding interactions among bio-inorganic interfaces, such that a rational design of biomolecules can be realized for the synthesis of highly active, green, multifunctional nanomaterials

Techno File: Silver and Gold.

Discover how silver and gold readily form nanoparticles during reduction firings (and gold in oxidation firings at mid range) that can be suspended in glazes to create unique colors

Sintering-Based In-Situ Synthesis and Characterization by TEM of Noble Metal Nanoparticles for Ceramic Glaze Color Control.

Gold and silver salt mixtures are incorporated in ceramic glazes for in situ development of mixtures of gold and silver nanoparticles (NPs) that subsequently allow for a wide spectrum of low metal loading color control within ceramic materials. Prior work has shown that gold NPs can be used to create vibrant, color-rich red pigments in high-temperature ceramic and glass applications, though the achievable diameter of the gold NP ultimately limits the available range of color. The current study significantly expands color control from traditional gold nanoparticle red through silver nanoparticle green via the alteration of gold-to-silver salt ratios incorporated in the glaze formulations prior to sintering. Nanoparticle-based coloring systems are tested in both oxidative and reductive firing atmospheres. While the oxidation environment is found to be prohibitive for silver NP stability, the reductive atmosphere is able to form and sustain mixtures of gold and silver NPs across a wide color spectrum. All glazes are analyzed via reflectance spectrometry for color performance and samples are characterized via TEM and EDS for composition and sizing trends. This study creates new groundwork for a color-controlled NP system based on noble metal ratio blends that are both nontoxic and achieved with radically lower metal pigment loading than traditional glazes

Sintering-Based In-Situ Synthesis and Characterization by TEM of Noble Metal Nanoparticles for Ceramic Glaze Color Control

Gold and silver salt mixtures are incorporated in ceramic glazes for in situ development of mixtures of gold and silver nanoparticles (NPs) that subsequently allow for a wide spectrum of low metal loading color control within ceramic materials. Prior work has shown that gold NPs can be used to create vibrant, color-rich red pigments in high-temperature ceramic and glass applications, though the achievable diameter of the gold NP ultimately limits the available range of color. The current study significantly expands color control from traditional gold nanoparticle red through silver nanoparticle green via the alteration of gold-to-silver salt ratios incorporated in the glaze formulations prior to sintering. Nanoparticle-based coloring systems are tested in both oxidative and reductive firing atmospheres. While the oxidation environment is found to be prohibitive for silver NP stability, the reductive atmosphere is able to form and sustain mixtures of gold and silver NPs across a wide color spectrum. All glazes are analyzed via reflectance spectrometry for color performance and samples are characterized via TEM and EDS for composition and sizing trends. This study creates new groundwork for a color-controlled NP system based on noble metal ratio blends that are both nontoxic and achieved with radically lower metal pigment loading than traditional glazes

Abstract 788: CK2α regulates MRP1 mediated multidrug drug resistance in cancer via phosphorylation of Thr249

Abstract We have previously shown that the function of Ycf1p, yeast ortholog of MRP1, is regulated by yeast casein kinase 2α (Cka1p) via phosphorylation at Ser251. In this study we explore whether CK2α, the human homolog of Cka1p, regulates MRP1 by phosphorylation at the semi-conserved site, Thr249. Knockdown of CK2α in MCF7-derived cells expressing MRP1 (MRP1 CK2β(−)) resulted in increased doxorubicin sensitivity. MRP1-dependent transport of LTC4 and E217αG into vesicles derived from MRP1 CK2β(−) cells was decreased compared with MRP1 vesicles. Moreover, Thr249 to alanine mutation (MRP1-T249A) also resulted in decreased MRP1-dependent transport, while a phosphomimicking mutation (MRP1-T249E) led to dramatic increase in MRP1-dependent transport. Studies in tissue culture confirmed these findings showing increased intracellular doxorubicin accumulation in MRP1 CK2β(−) and MRP1-T249A cells compared to MRP1 cells. Inhibition of CK2 kinase by DMAT resulted in increased doxorubicin accumulation in MRP1 cells, but not in MRP1 CK2β(−), MRP1-T249A or MRP1-T249E cells, suggesting that CK2α regulates MRP1 function via phosphorylation of Thr249. Indeed, CK2α and MRP1 interact physically and recombinant CK2 phosphorylates MRP1 derived peptide in vitro in Thr249 dependent manner, while knockdown of CK2α results in decreased phosphorylation at MRP1-T249. The role of CK2 in regulating MRP1 was confirmed in other cancer cell lines where CK2 inhibition decreased MRP1-mediated efflux of doxorubicin. This study supports a model in which CK2α potentiates MRP1 function via direct phosphorylation of Thr249. We believe that addition of CK2 inhibitors to cancer treatments will improve therapeutic outcome in part due to reversal of MRP1- mediated drug resistance. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 788. doi:1538-7445.AM2012-788</jats:p