Non-chemisorbed gold–sulfur binding prevails in self-assembled monolayers

Inkpen, Michael S.; Liu, Fulai; Li, Haixing; Campos, Luis M.; Neaton, Jeffrey B.; Venkataraman, Latha

doi:10.1038/s41557-019-0216-y

Cited by 221 publications

(207 citation statements)

References 54 publications

Supporting

Mentioning

194

Contrasting

Unclassified

Order By: Relevance

“…It is important to note that the natural oxidation of thiol groups exposed to air atmosphere produces typically sulfenic acid, sulfide, and sulfoxide . The formation of disulfide suggests catalyzed reaction probably promoted by the presence of AuNPs that is interesting for future investigations …”

Section: Resultsmentioning

confidence: 99%

Nanostructured Hematite Decorated with Gold Nanoparticles for Functionalization and Biocompatibility

Menezes

Sombrio

Costa

et al. 2019

Physica Status Solidi (a)

View full text Add to dashboard Cite

Iron oxides have attracted the attention of researchers due to their abundance, low cost, low toxicity, and versatility of applications. According to the composition and crystalline structure, iron oxides may have characteristics of semiconductors and magnetic materials, such as hematite (α‐Fe2O3) and magnetite (Fe3O4), respectively. The property of biocompatibility of hematite is essential to be applied in the construction of micro‐/nanorobots (MNRs). Herein, the decoration of hierarchically structured core/shell Fe3O4/Fe2O3 microtubes and foils with gold nanoparticles (AuNPs) for functionalization and enhancement of biocompatibility that favor the use in MNR fabrication is presented. In this case, the synthesis of AuNPs takes advantage of the capacity of hematite to reduce Au3+ photochemically under excitation by a sunlight simulator. The yield of AuNPs covering the microtube surface is dependent on the gold salt concentration used for the synthesis. The AuNP‐decorated hematite surfaces of the microtube and foil are functionalized with thiol poly(ethylene glycol) fluorescein, exhibiting increase in conductivity favored by irradiation with visible light. AuNPs also favor cell adherence and proliferation with the maintenance of mitochondrial transmembrane potential. Therefore, the hematite surface of the microtubes decorated with AuNPs is a promising material for the application in micro‐/nanorobots and bioelectronics.

show abstract

Section: Resultsmentioning

confidence: 99%

Nanostructured Hematite Decorated with Gold Nanoparticles for Functionalization and Biocompatibility

Menezes

Sombrio

Costa

et al. 2019

Physica Status Solidi (a)

View full text Add to dashboard Cite

show abstract

“…As a result, the spectra changes are slower and more uniform during the reaction process. For the PEG‐modified AuNRs, SH‐PEG are chemically absorbed onto the surface of gold nanorods forming Au‐S covalent bonds in homogeneous solutions . PEG modification is likely to increase the surface energy of {110} plane, resulting in almost equal surface energy throughout the entire AuNR.…”

Section: Resultsmentioning

confidence: 99%

Direct observation of single plasmonic metal nanoparticle reaction in microcolumn with chromatic‐aberration‐free LASER light‐sheet scattering imaging

et al. 2019

View full text Add to dashboard Cite

Direct observation and characterization of individual noble metal nanoparticles (MNPs) and their chemical reactions have attracted much attention owing to their unique physical and chemical properties and extensive applications. To achieve high‐throughput information‐rich evaluation of MNPs, it would be advantageous to combine highly efficient microcolumn separation technology with on‐column high resolution plasmonic imaging technique. Here, with a chromatic aberration‐suppressed supercontinuum laser light‐sheet scattering imaging system and colorimetric detection, we monitored oxidation process of single gold nanorods inside a capillary under gravity driven flow, and observed heterogenous reaction intermediates and pathways for different MNP surface modifications. The results suggest that molecular interactions and bindings with MNPs have a significant impact on their reaction kinetics. This high‐throughput on‐line single particle detection technique could be potentially applied to chemical and biochemical reaction studies of other MNPs.

show abstract

“…For instance, a previous study on homopeptides suggested that bonding could be established via physisorption of a tryptophan unit onto gold, 30 and other binding configurations for the thiolate or carboxylate groups have been explored. [51][52][53][54] In the experiments, variable SAM heights between 20 and 26 Å have been observed. This means that molecules may be slightly tilted or crumpled in the ensemble junctions.…”

Section: Theoretical Methodsmentioning

confidence: 91%

Doping hepta-alanine with tryptophan: A theoretical study of its effect on the electrical conductance of peptide-based single-molecule junctions

Schosser

Zotti

Cuevas

et al. 2019

The Journal of Chemical Physics

View full text Add to dashboard Cite

Motivated by a recent experiment [C. Guo et al., Proc. Natl. Acad. Sci. U. S. A. 113, 10785 (2016)], we carry out a theoretical study of electron transport through peptide-based single-molecule junctions. We analyze the pristine hepta-alanine and its functionalizations with a single tryptophan unit, which is placed in three different locations along the backbone. Contrary to expectations from the experiment on self-assembled monolayers, we find that insertion of tryptophan does not raise the electrical conductance and that the resulting peptides instead remain insulating in the framework of a coherent transport picture. The poor performance of these molecules as conductors can be ascribed to the strongly off-resonant transport and low electrode-molecule coupling of the frontier orbitals. Although the introduction of tryptophan increases the energy of the highest occupied molecular orbital (HOMO) of the peptides in the gas phase, the new HOMO states are localized on the tryptophan unit and therefore essentially do not contribute to coherent charge transport.Published under license by AIP Publishing. https://doi.

show abstract

Non-chemisorbed gold–sulfur binding prevails in self-assembled monolayers

Cited by 221 publications

References 54 publications

Nanostructured Hematite Decorated with Gold Nanoparticles for Functionalization and Biocompatibility

Nanostructured Hematite Decorated with Gold Nanoparticles for Functionalization and Biocompatibility

Direct observation of single plasmonic metal nanoparticle reaction in microcolumn with chromatic‐aberration‐free LASER light‐sheet scattering imaging

Doping hepta-alanine with tryptophan: A theoretical study of its effect on the electrical conductance of peptide-based single-molecule junctions

Contact Info

Product

Resources

About