Porphyrin self-assembled monolayers and photodynamic oxidation of tryptophan

2010 ◽  
Vol 14 (01) ◽  
pp. 81-88 ◽  
Author(s):  
Isabelle Chambrier ◽  
David A. Russell ◽  
Derek E. Brundish ◽  
William G. Love ◽  
Giulio Jori ◽  
...  
Keyword(s):  
Human Serum Albumin ◽  
Fluorescence Spectroscopy ◽  
Serum Albumin ◽  
White Light ◽  
Self Assembled Monolayers ◽  
Self Assembled Monolayer ◽  
Glass Substrates ◽  
Assembled Monolayers ◽  
Self Assembled ◽  
Derivatives Of

The zinc and magnesium metalated derivatives of 5,5′-[12,12′-di(thiododecyloxy)-4,4′-phenyl)]-10,10′,15,15′,20,20′-hexakis(3,3′,4,4′,5,5′-hexakisdecyloxyphenyl)diporphyrin, 1b and 1c, have been synthesised and deposited to form self-assembled monolayer (SAM) films on the surface of gold-coated glass substrates. The SAM films have been characterized by RAIR spectroscopy and fluorescence spectroscopy. The potential for the porphyrin films to catalyze the oxidation of tryptophan within human serum albumin upon irradiation with white light has been demonstrated and attributed to the porphyrins acting as photosensitizers of oxygen to form oxidizing species.

Neutron and X-ray Reflectivity Studies of Human Serum Albumin Adsorption onto Functionalized Surfaces of Self-Assembled Monolayers

1997 ◽  
Vol 13 (5) ◽  
pp. 635-639 ◽  
Author(s):  
S. Petrash ◽  
A. Liebmann-Vinson ◽  
M.D. Foster ◽  
L.M. Lander ◽  
W.J. Brittain ◽  
...  
Keyword(s):  
Human Serum Albumin ◽  
Serum Albumin ◽  
Human Serum ◽  
Self Assembled Monolayers ◽  
X Ray ◽  
Functionalized Surfaces ◽  
Assembled Monolayers ◽  
Self Assembled ◽  
Albumin Adsorption

Evanescent wave excitation of palladium metalated porphyrins as self-assembled monolayers and phosphorescence quenching by oxygen

2012 ◽  
Vol 16 (11) ◽  
pp. 1186-1195 ◽  
Author(s):  
Zhenxin Wang ◽  
Shaya Y. Al-Raqa ◽  
Isabelle Chambrier ◽  
David A. Russell ◽  
Michael J. Cook
Keyword(s):  
Luminescence Spectroscopy ◽  
Self Assembled Monolayers ◽  
The Novel ◽  
Self Assembled Monolayer ◽  
Phosphorescence Quenching ◽  
Glass Slides ◽  
Assembled Monolayers ◽  
Phosphorescence Emission ◽  
Self Assembled ◽  
Derivatives Of

The novel palladium metalated derivatives of 5,5′-[8,8′-di(thiooctyloxy)-4,4′-phenyl)]-10,10′,15,15′,20,20′-hexakis(4,4′-t-butylphenyl)diporphyrin and 5,5′-[8,8′-di(thiooctyloxy)-4,4′-phenyl)]- 10,10′,15,15′,20,20′-hexakis(3,3′,4,4′,5,5′-hexakisdecyloxyphenyl)diporphyrin, 1 and 2 respectively, have been synthesized and deposited to form self-assembled monolayer (SAM) films on gold-coated glass slides that served as substrates. The SAM films have been characterised by RAIR spectroscopy. Excitation of the molecules within the films has been achieved using the evanescent field arising when the glass substrate was used as a waveguide. Luminescence spectroscopy detected both fluorescence and phosphorescence emission from the SAM films under an argon atmosphere. Quenching of the phosphorescence emission by dioxygen was investigated for both films. Greater reproducibility of data was achieved from the SAM films of compound 2. The phosphorescence quenching from these films followed the Stern–Volmer relationship.

Changes in Protein Adsorption on Self-Assembled Monolayers with Monolayer Order:  Comparison of Human Serum Albumin and Human Gamma Globulin

Langmuir ◽  
2001 ◽  
Vol 17 (24) ◽  
pp. 7645-7651 ◽  
Author(s):  
Stanislaw Petrash ◽  
Tricia Cregger ◽  
Bin Zhao ◽  
Elena Pokidysheva ◽  
Mark D. Foster ◽  
...  
Keyword(s):  
Human Serum Albumin ◽  
Serum Albumin ◽  
Human Serum ◽  
Protein Adsorption ◽  
Gamma Globulin ◽  
Self Assembled Monolayers ◽  
Assembled Monolayers ◽  
Self Assembled ◽  
Human Gamma Globulin ◽  
Order Comparison

Effect of Flow on Human Serum Albumin Adsorption to Self-Assembled Monolayers of Varying Packing Density

Langmuir ◽  
2003 ◽  
Vol 19 (13) ◽  
pp. 5464-5474 ◽  
Author(s):  
Eugene J. Choi ◽  
Mark D. Foster ◽  
Susan Daly ◽  
Robert Tilton ◽  
Todd Przybycien ◽  
...  
Keyword(s):  
Human Serum Albumin ◽  
Serum Albumin ◽  
Human Serum ◽  
Packing Density ◽  
Self Assembled Monolayers ◽  
Assembled Monolayers ◽  
Self Assembled ◽  
Albumin Adsorption

Laser Polishing of Cold Work Steel AISI D2 for Dry Metal Forming Tools: Surface Homogenization, Refinement and Preparation for Self-Assembled Monolayers

2018 ◽  
Vol 767 ◽  
pp. 69-76 ◽  
Author(s):  
Ingo Ross ◽  
André Temmler ◽  
Moritz Küpper ◽  
Stephan Prünte ◽  
Marco Teller ◽  
...  
Keyword(s):  
Cold Extrusion ◽  
Self Assembled Monolayers ◽  
Homogeneous Distribution ◽  
Self Assembled Monolayer ◽  
Pulsed Laser Radiation ◽  
Laser Polishing ◽  
Assembled Monolayers ◽  
Aisi D2 ◽  
Self Assembled ◽  
Forming Tools

Liquid lubrication guarantees high precision and surface quality of workpieces in industrial forming processes. In the case of aluminum cold extrusion, wear and cold welding due to direct contact of tool and workpiece are usually prevented by the extensive use of lubricants. Since the use of lubricants is economically and ecologically unfavorable, surface treatments of tools by, e.g. laser polishing and/or coatings are in the focus of current investigations to substitute these lubricants and establish so called “dry metal forming” processes. The material AISI D2, a ledeburitic 12% chromium steel which is known to have a significant amount of chromium carbide precipitations, is widely used in cold extrusion for forming tools. The large fraction of chromium carbide precipitations, however, hinder the formation of a dense self-assembled monolayer (SAM) that is necessary to avoid direct contact of reactive aluminum with surface oxides of the tool. Therefore, a homogeneous distribution of the chemical elements with a smaller fraction or no chromium carbides in the steel matrix, particularly in the tool surface, is aimed for. Using laser polishing, the surface layer is molten by continuous or pulsed laser radiation. Within the melt pool, the elementary distribution is homogenized as a result of thermal convection and diffusion processes, as well as a smoothed surface and a grain refinement are achieved. Consequently, the effects of the surface treatment by laser polishing on the area coverage of self-assembled monolayers are investigated. Thus, a combined surface treatment by laser polishing and functionalization with a dense self-assembled monolayer shall reduce overall adhesive wear. For this investigation, several specimens of conventional manufactured and powder metallurgical molten AISI D2 are laser polished using continuous or pulsed laser radiation or a combination of both. The resulting surfaces are investigated by microscopy and spectroscopic techniques to analyze the surface topography and the elemental distribution near to the surface. These results are compared to those of conventionally hand-polished specimens. Furthermore, the influence of the element homogenization and grain refinement on the area coverage of self-assembled monolayers is explored. First results show that laser polishing of AISI D2 is suitable to achieve a reduction of grain size and a more homogeneous distribution of chromium carbides within the surface layer.

Spectral and cyclic voltammetric characterization of self-assembled monolayers on gold of pyrene end-labeled oligonucleotide duplexes

1999 ◽  
Vol 77 (5-6) ◽  
pp. 1077-1084 ◽  
Author(s):  
R Scott Reese ◽  
Marye Anne Fox
Keyword(s):  
Gold Surface ◽  
Self Assembled Monolayers ◽  
Self Assembled Monolayer ◽  
Surface Emission ◽  
Assembled Monolayers ◽  
Oligonucleotide Duplex ◽  
Self Assembled ◽  
Duplex Formation

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.

Self-Assembled Monolayers of 12-Mercaptododecylphosphonic Acid on Titania Particles; Application to the Extraction of Heavy Metals

2004 ◽  
Vol 847 ◽  
Author(s):  
Sébastien Anthérieu ◽  
Florence Brodard-Séverac ◽  
Gilles Guerrero ◽  
P. Hubert Mutin
Keyword(s):  
Heavy Metals ◽  
Chemical Analysis ◽  
Phosphonic Acid ◽  
Metal Extraction ◽  
Self Assembled Monolayers ◽  
Extraction Ability ◽  
Self Assembled Monolayer ◽  
Inorganic Hybrid ◽  
Assembled Monolayers ◽  
Self Assembled

ABSTRACTTitania particles (P25 DEGUSSA AG) were treated by a solution of 12-mercaptododecyl-phosphonic acid (MDPA) in toluene to obtain an organic-inorganic hybrid material with thiol functions at the surface. This material was characterized by chemical analysis, solid state 31P MAS NMR and FTIR spectroscopies, and XPS. Reaction of the phosphonic acid end of MDPA with the TiO2 surface led to the formation of a relatively dense and well-ordered self-assembled monolayer (SAM), with a density of about 3.9 SH functions per nm2. This material was tested for the extraction of mercury in water at pH 7, 9, and 11. Chemical analysis indicated no loss of SH functionality, even at pH 11. The best extraction results were obtained at pH 9 and 11, with a metal extraction ability between 85 and 90%.

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