Work function modification of the (111) gold surface covered by long alkanethiol-based self-assembled monolayers

Self-assembled monolayers of sulfur-terminated oligonucleotide duplexes were formed on flat gold surfaces, either by exposure of a self-assembled monolayer bearing one oligonucleotide strand to the complementary strand or by preformation of a oligonucleotide duplex that was then deposited on a fresh gold surface. Virtually identical spectral behavior was observed whether the duplex was produced before deposition or by in situ complementary association. With a duplex bearing an appropriate pyrene end-label, the resulting thin film was photoresponsive. Surface emission measurements show no evidence for pyrene aggregation on the modified surfaces. The polarity of the photocurrent, reflecting photoinduced electron transfer initiated by photoexcitation of pyrene, is opposite that expected from the oligonucleotide-mediated reduction of the appended pyrene excited state.Key words: oligonucleotide, self-assembled monolayer, duplex formation, photoelectrochemistry, surface emission.

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Density Functional Theory with Modified Dispersion Correction for Metals Applied to Self-Assembled Monolayers of Thiols on Au(111)

Journal of Theoretical Chemistry ◽

10.1155/2013/327839 ◽

2013 ◽

Vol 2013 ◽

pp. 1-9 ◽

Cited By ~ 29

Author(s):

M. P. Andersson

Keyword(s):

Density Functional Theory ◽

Density Functional ◽

Dimethyl Disulfide ◽

Gold Surface ◽

Self Assembled Monolayers ◽

Dispersion Correction ◽

Dissociative Chemisorption ◽

Functional Theory ◽

Assembled Monolayers ◽

Self Assembled

Using sound physical principles we modify the DFT-D2 atom pairwise semiempirical dispersion correction to density functional theory to work for metallic systems and in particular self-assembled monolayers of thiols on gold surfaces. We test our approximation for two functionals PBE-D and revPBE-D for lattice parameters and cohesive energies for Ni, Pd, Pt, Cu, Ag, and Au, adsorption energies of CO on (111) surfaces of Pd, Pt, Cu, Ag, and Au, and adsorption energy of benzene on Ag(111) and Au(111). Agreement with experimental data is substantially improved. We apply the method to self-assembled monolayers of alkanethiols on Au(111) and find reasonable agreement for PBE-D and revPBE-D for both physisorption of n-alkanethiols as well as dissociative chemisorption of dimethyl disulfide as an Au-adatom-dithiolate complex. By modifying the C6 coefficient for Au, we obtain quantitative agreement for physisorption and chemisorption for both PBE-D and revPBE-D using the same set of parameters. Our results confirm that inclusion of dispersion forces is crucial for any quantitative analysis of the thiol and thiolate bonds to the gold surface using quantum chemical calculations.

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Self-Assembled Monolayers of Hexapeptides on Gold: Surface Characterization and Orientation Distribution Analysis†

The Journal of Physical Chemistry A ◽

10.1021/jp047922z ◽

2004 ◽

Vol 108 (45) ◽

pp. 9673-9681 ◽

Cited By ~ 26

Author(s):

Xingu Wen ◽

Richard W. Linton ◽

Fernando Formaggio ◽

Claudio Toniolo ◽

Edward T. Samulski

Keyword(s):

Surface Characterization ◽

Gold Surface ◽

Orientation Distribution ◽

Self Assembled Monolayers ◽

Distribution Analysis ◽

Assembled Monolayers ◽

Self Assembled

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Effect of surface chemical composition on the work function of silicon substrates modified by binary self-assembled monolayers

Physical Chemistry Chemical Physics ◽

10.1039/c1cp20590k ◽

2011 ◽

Vol 13 (33) ◽

pp. 15122 ◽

Cited By ~ 20

Author(s):

Che-Hung Kuo ◽

Chi-Ping Liu ◽

Szu-Hsian Lee ◽

Hsun-Yun Chang ◽

Wei-Chun Lin ◽

...

Keyword(s):

Chemical Composition ◽

Work Function ◽

Self Assembled Monolayers ◽

Silicon Substrates ◽

Surface Chemical ◽

Surface Chemical Composition ◽

Assembled Monolayers ◽

Self Assembled ◽

Effect Of Surface

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Specific Immobilization of Streptavidin on Mixed Self-Assembled Monolayers as Mixing Ratio

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.121-123.495 ◽

2007 ◽

Vol 121-123 ◽

pp. 495-498 ◽

Cited By ~ 4

Author(s):

Jun Hyung Park ◽

Buyng Su Park ◽

Gu Huh ◽

Seung Hyun Lee ◽

Hyun Sook Lee ◽

...

Keyword(s):

Colorimetric Detection ◽

Gold Surface ◽

Self Assembled Monolayers ◽

Scanning Tunneling ◽

Local Domain ◽

Mixing Ratio ◽

Tunneling Microscopy ◽

Self Assembled Monolayer ◽

Assembled Monolayers ◽

Self Assembled

We report on the distribution of mixed self-assembled monolayers (SAMs) composed of biotinylated and diluent alkylthiolates for streptavidin immobilization. Two thiol derivatives, 11-mercapto-1-undecanol (MUOH) and 11-mercaptoundecanoic-(8-biotinylamido-3,6-dioxaoctyl) amide (MBDA), were employed for mixed SAM. These thiols formed self-assembled monolayer without local domain, and streptavidins were immobilized onto biotinylated gold surface without nonspecific binding. In order to find the optimized condition of immobilization of streptavidin, we controlled the mixing ratio of two kind thiols by colorimetric detection assay, and the immobilization was characterized by atomic force microscopy (AFM), scanning tunneling microscopy (STM), and ellipsometer.

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Adsorption and desorption of self-assembled L-cysteine monolayers on nanoporous gold monitored by in situ resistometry

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.10.219 ◽

2019 ◽

Vol 10 ◽

pp. 2275-2279

Author(s):

Elisabeth Hengge ◽

Eva-Maria Steyskal ◽

Rupert Bachler ◽

Alexander Dennig ◽

Bernd Nidetzky ◽

...

Keyword(s):

Gold Surface ◽

Research Field ◽

Nanoporous Gold ◽

Self Assembled Monolayers ◽

Initial Surface ◽

Resistance Change ◽

Adsorption And Desorption ◽

Assembled Monolayers ◽

Self Assembled

Surface modifications of nanoporous metals have become a highly attractive research field as they exhibit great potential for various applications, especially in biotechnology. Using self-assembled monolayers is one of the most promising approaches to modify a gold surface. However, only few techniques are capable of characterizing the formation of these monolayers on porous substrates. Here, we present a method to in situ monitor the adsorption and desorption of self-assembled monolayers on nanoporous gold by resistometry, using cysteine as example. During the adsorption an overall relative change in resistance of 18% is detected, which occurs in three distinct stages. First, the cysteine molecules are adsorbed on the outer surface. In the second stage, they are adsorbed on the internal surfaces and in the last stage the reordering accompanied by additional adsorption takes place. The successful binding of cysteine on the Au surface was confirmed by cyclic voltammetry, which showed a significant decrease of the double-layer capacitance. Also, the electrochemically controlled desorption of cysteine was monitored by concomitant in situ resistometry. From the desorption peak related to the (111) surface of the structure, which is associated with a resistance change of 4.8%, an initial surface coverage of 0.48 monolayers of cysteine could be estimated.

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