Electrosynthesis of polydopamine-ethanolamine films for the development of immunosensing interfaces

AbstractWe report a straightforward and reproducible electrochemical approach to develop polydopamine-ethanolamine (ePDA-ETA) films to be used as immunosensing interfaces. ETA is strongly attached to polydopamine films during the potentiodynamic electropolymerization of dopamine. The great advantage of the electrochemical methods is to generate the oxidized species (quinones), which can readily react with ETA amine groups present in solution, with the subsequent incorporation of this molecule in the polymer. The presence of ETA and its effect on the electrosynthesis of polydopamine was accessed by cyclic voltammetry, ellipsometry, atomic force microscopy, FTIR and X-ray photoelectron spectroscopy. The adhesive and biocompatible films enable a facile protein linkage, are resilient to flow assays, and display intrinsic anti-fouling properties to block non-specific protein interactions, as monitored by real-time surface plasmon resonance, and confirmed by ellipsometry. Immunoglobulin G (IgG) and Anti-IgG were used in this work as model proteins for the affinity sensor. By using the one-step methodology (ePDA-ETA), the lower amount of immobilized biorecognition element, IgG, compared to that deposited on ePDA or on ETA post-modified film (ePDA/ETA), allied to the presence of ETA, improved the antibody-antigen affinity interaction. The great potential of the developed platform is its versatility to be used with any target biorecognition molecules, allowing both optical and electrochemical detection.

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Superhydrophilic Coating with Antibacterial and Oil-Repellent Properties via NaIO4-Triggered Polydopamine/Sulfobetaine Methacrylate Polymerization

Polymers ◽

10.3390/polym12092008 ◽

2020 ◽

Vol 12 (9) ◽

pp. 2008

Author(s):

Hsiu-Wen Chien ◽

Hong-Yu Lin ◽

Chau-Yi Tsai ◽

Tai-Yu Chen ◽

Wei-Nian Chen

Keyword(s):

Surface Modification ◽

Photoelectron Spectroscopy ◽

Deposition Process ◽

Water Contact ◽

Water Separation ◽

Force Microscopy ◽

Atomic Force ◽

Oil Water Separation ◽

One Step ◽

Oil Repellent

Superhydrophilic coatings have been widely used for the surface modification of membranes or biomedical devices owing to their excellent antifouling properties. However, simplifying the modification processes of such materials remains challenging. In this study, we developed a simple and rapid one-step co-deposition process using an oxidant trigger to fabricate superhydrophilic surfaces based on dopamine chemistry with sulfobetaine methacrylate (SBMA). We studied the effect of different oxidants and SBMA concentrations on surface modification in detail using UV–VIS spectrophotometry, dynamic light scattering, atomic force microscopy, X-ray photoelectron spectroscopy, and surface plasmon resonance. We found that NaIO4 could trigger the rate of polymerization and the optimum ratio of dopamine to SBMA is 1:25 by weight. This makes the surface superhydrophilic (water contact angle < 10°) and antifouling. The superhydrophilic coating, when introduced to polyester membranes, showed great potential for oil/water separation. Our study provides a complete description of the simple and fast preparation of superhydrophilic coatings for surface modification based on mussel-inspired chemistry.

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Diameter-Selective Solubilization of Carbon Nanotubes by Lipid Micelles

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2008.104 ◽

2008 ◽

Vol 8 (1) ◽

pp. 420-423 ◽

Cited By ~ 14

Author(s):

Dimitrios Tasis ◽

Konstantinos Papagelis ◽

Dionysios Douroumis ◽

James R. Smith ◽

Nikolaos Bouropoulos ◽

...

Keyword(s):

Carbon Nanotubes ◽

Carbon Nanostructures ◽

Aqueous Suspension ◽

Aqueous Media ◽

Microscopy Imaging ◽

Force Microscopy ◽

Atomic Force ◽

One Step ◽

The One ◽

Walled Carbon Nanotubes

The one-step dispersion of HiPco single-walled carbon nanotubes in aqueous media with the use of a synthetic lyso-phosphatidylcholine was studied. Solubilization occurs through wrapping of lipid molecules around the circumference of the tubes, yielding lipid monolayers on the graphitic sidewalls as evidenced by atomic force microscopy imaging and dynamic light scattering measurements. Raman spectroscopy showed that the dispersion and centrifugation process leads to an effective enrichment of the stable aqueous suspension in carbon nanostructures with smaller diameters.

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Cleaning of graphene surfaces by low-pressure air plasma

Royal Society Open Science ◽

10.1098/rsos.172395 ◽

2018 ◽

Vol 5 (5) ◽

pp. 172395 ◽

Cited By ~ 7

Author(s):

Phuong Viet Pham

Keyword(s):

Photoelectron Spectroscopy ◽

Graphene Film ◽

Chemical Vapour ◽

Optical Microscope ◽

Pristine Graphene ◽

Air Plasma ◽

Graphene Surface ◽

Force Microscopy ◽

Atomic Force ◽

The One

The polymer residues still present on a chemical vapour-deposited graphene surface after its wet transfer by the poly(methyl methacrylate) method to the arbitrary substrates, tend to cause problems such as electrical degradation and unwanted intentional doping. In this study, by using an effective cleaning method for the graphene surface by air-assisted plasma, the graphene surface was cleaned significantly without damaging the graphene network, which resulted in the reduction (approx. 71.11%) of polymer residues on its surface. The analysis reveals that this approach reduced the D-band (impurities, polymer residues) formation while maintaining the π-bonding of the graphene, which affects conductivity. By characterizations of the optical microscope, Raman spectroscopy and atomic force microscopy, we obtained a significantly cleaner graphene surface (roughness of 4.1 nm) compared to pristine graphene (roughness of 1.2 nm) on a SiO 2 substrate. In addition, X-ray photoelectron spectroscopy data revealed that the C1s peak of the air-assisted graphene film was higher than the one of a pristine graphene film, indicating that a cleaner graphene surface was obtained.

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Blue/White Emission from Hydrogenated Amorphous Silicon Carbide Films Prepared by PECVD

MRS Proceedings ◽

10.1557/proc-1153-a16-01 ◽

2009 ◽

Vol 1153 ◽

Cited By ~ 1

Author(s):

Volodymyr Ivashchenko ◽

Andrey Vasin ◽

L. A. Ivashchenko ◽

P. L. Skrynskyy

Keyword(s):

Silicon Carbide ◽

Photoelectron Spectroscopy ◽

Chemical Vapor ◽

Substrate Bias ◽

Double Peak ◽

Hydrogenated Silicon ◽

X Ray ◽

Force Microscopy ◽

Atomic Force ◽

The One

AbstractPhotoluminescence (PL) from hydrogenated silicon carbide (SiC:H) films is studied at room temperature. The films were deposited by plasma-enhanced chemical vapor (PECVD) technique with and without substrate bias using methyltrichlorosilane as a main precursor. After the deposition the samples were annealed at various temperatures in vacuum. The films were characterized by atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). The samples deposited without substrate bias (series A) were amorphous, whereas the samples deposited with negative substrate bias -100V (series B) were nanocrystalline. The one-peak (470 nm) and double-peak (415 and 437 nm) PL structures of the as-deposited samples A and B were observed, respectively. Annealing strongly enhanced intensity of PL of the samples B and trandformed PL spectrum from double-peak into broad featureless band with intensity at about 470 nm. The blue PL in as-deposited films B is supposed to be assigned to the radiative recombination in the sites located at the nanocrystallite surface, whereas the photo excitation of carries mostly occurs in nanocrystallite cores. A further increase in annealing temperature causes hydrogen effusion, which leads to an increase of the concentration of non-raidative recombination centers associated with dangling-bonds and as a result, to the quenching of PL.

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One-Step Potentiostatic Electrodeposition of Polypyrrole Coatings on Zinc Coated Steel Surfaces

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.415.65 ◽

2009 ◽

Vol 415 ◽

pp. 65-68 ◽

Cited By ~ 6

Author(s):

Cristian Pirvu ◽

Mihaela Mindroiu ◽

Ioana Demetrescu

Keyword(s):

Electrochemical Impedance ◽

Corrosion Current ◽

Coated Steel ◽

Metallic Surfaces ◽

Force Microscopy ◽

Atomic Force ◽

Counter Ions ◽

One Step ◽

Zinc Coated Steel ◽

The One

In this paper the elaboration and characterization of polypyrrole coatings on active metallic surfaces were performed. The one-step electropolymerization of pyrrole on zinc-coated steel electrodes was investigated under several techniques (cyclic voltammetry, electrochemical impedance spectroscopy, atomic force microscopy) in aqueous medium. Adherent and homogeneous PPy coatings were obtained using tartrate counter-ions. The obtained results show that the PPy coatings increase the corrosion potential and reduce the corrosion current.

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Forming nanoparticles of water-soluble ionic molecules and embedding them into polymer and glass substrates

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.3.30 ◽

2012 ◽

Vol 3 ◽

pp. 267-276 ◽

Cited By ~ 30

Author(s):

Stella Kiel ◽

Olga Grinberg ◽

Nina Perkas ◽

Jerome Charmet ◽

Herbert Kepner ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Ultrasonic Waves ◽

Water Soluble ◽

X Ray ◽

Force Microscopy ◽

Glass Substrates ◽

Atomic Force ◽

One Step ◽

Ultrasound Assisted ◽

Physical And Chemical

This work describes a general method for the preparation of salt nanoparticles (NPs) made from an aqueous solution of ionic compounds (NaCl, CuSO4 and KI). These nanoparticles were created by the application of ultrasonic waves to the aqueous solutions of these salts. When the sonication was carried out in the presence of a glass microscope slide, a parylene-coated glass slide, or a silicon wafer the ionic NPs were embedded in these substrates by a one-step, ultrasound-assisted procedure. Optimization of the coating process resulted in homogeneous distributions of nanocrystals, 30 nm in size, on the surfaces of the substrates. The morphology and structure of each of the coatings were characterized by physical and chemical methods, such as X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). After 24 h of leaching into water the nanoparticles of the inorganic salts were still present on the slides, and complete leaching of nanoparticles occurred only after 96 h. A mechanism of the ultrasound-assisted coating is proposed.

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Investigation of the Effect of Uv-Assisted Oxidation and Nitridation of Hafnium Metal Films

MRS Proceedings ◽

10.1557/proc-780-y5.5 ◽

2003 ◽

Vol 780 ◽

Author(s):

C. Essary ◽

V. Craciun ◽

J. M. Howard ◽

R. K. Singh

Keyword(s):

Uv Radiation ◽

Photoelectron Spectroscopy ◽

Grazing Angle ◽

X Ray Diffraction ◽

Metal Thin Films ◽

X Ray ◽

Force Microscopy ◽

Si Substrates ◽

Atomic Force ◽

Silicon Interface

AbstractHf metal thin films were deposited on Si substrates using a pulsed laser deposition technique in vacuum and in ammonia ambients. The films were then oxidized at 400 °C in 300 Torr of O2. Half the samples were oxidized in the presence of ultraviolet (UV) radiation from a Hg lamp array. X-ray photoelectron spectroscopy, atomic force microscopy, and grazing angle X-ray diffraction were used to compare the crystallinity, roughness, and composition of the films. It has been found that UV radiation causes roughening of the films and also promotes crystallization at lower temperatures.Furthermore, increased silicon oxidation at the interface was noted with the UVirradiated samples and was shown to be in the form of a mixed layer using angle-resolved X-ray photoelectron spectroscopy. Incorporation of nitrogen into the film reduces the oxidation of the silicon interface.

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Photocatalytic reduction of graphene oxide with cuprous oxide film under UV-vis irradiation

REVIEWS ON ADVANCED MATERIALS SCIENCE ◽

10.1515/rams-2020-0022 ◽

2020 ◽

Vol 59 (1) ◽

pp. 207-214 ◽

Cited By ~ 1

Author(s):

Yao Wang ◽

Jianqing Feng ◽

Lihua Jin ◽

Chengshan Li

Keyword(s):

Graphene Oxide ◽

Photoelectron Spectroscopy ◽

Low Cost ◽

Photocatalytic Reduction ◽

Force Microscopy ◽

Atomic Force ◽

Reduced Graphene ◽

Reduction Efficiency ◽

Metal Organic ◽

Reduction Effect

AbstractWe have grown Cu2O films by different routes including self-oxidation and metal-organic deposition (MOD). The reduction efficiency of Cu2O films on graphene oxide (GO) synthesized by modified Hummer’s method has been studied. Surface morphology and chemical state of as-prepared Cu2O film and GO sheets reduced at different conditions have also been investigated using atomic force microscopy (AFM) and x-ray photoelectron spectroscopy (XPS). Results show that self-oxidation Cu2O film is more effective on phtocatalytic reduction of GO than MOD-Cu2O film. Moreover, reduction effect of self-oxidation Cu2O film to GO is comparable to that of environmental-friendly reducing agent of vitamin C. The present results offer a potentially eco-friendly and low-cost approach for the manufacture of reduced graphene oxide (RGO) by photocatalytic reduction.

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Interface Structures and Electronic States of Epitaxial Tetraazanaphthacene on Single-Crystal Pentacene

Materials ◽

10.3390/ma14051088 ◽

2021 ◽

Vol 14 (5) ◽

pp. 1088

Author(s):

Yuki Gunjo ◽

Hajime Kamebuchi ◽

Ryohei Tsuruta ◽

Masaki Iwashita ◽

Kana Takahashi ◽

...

Keyword(s):

Single Crystal ◽

Photoelectron Spectroscopy ◽

Grazing Incidence ◽

Force Microscopy ◽

Interface Dipole ◽

Atomic Force ◽

Interfacial Structures ◽

Donor And Acceptor ◽

A Charge ◽

Interface Structures

The structural and electronic properties of interfaces composed of donor and acceptor molecules play important roles in the development of organic opto-electronic devices. Epitaxial growth of organic semiconductor molecules offers a possibility to control the interfacial structures and to explore precise properties at the intermolecular contacts. 5,6,11,12-tetraazanaphthacene (TANC) is an acceptor molecule with a molecular structure similar to that of pentacene, a representative donor material, and thus, good compatibility with pentacene is expected. In this study, the physicochemical properties of the molecular interface between TANC and pentacene single crystal (PnSC) substrates were analyzed by atomic force microscopy, grazing-incidence X-ray diffraction (GIXD), and photoelectron spectroscopy. GIXD revealed that TANC molecules assemble into epitaxial overlayers of the (010) oriented crystallites by aligning an axis where the side edges of the molecules face each other along the [1¯10] direction of the PnSC. No apparent interface dipole was found, and the energy level offset between the highest occupied molecular orbitals of TANC and the PnSC was determined to be 1.75 eV, which led to a charge transfer gap width of 0.7 eV at the interface.

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Silane-Coating Strategy for Titanium Functionalization Does Not Impair Osteogenesis In Vivo

Materials ◽

10.3390/ma14071814 ◽

2021 ◽

Vol 14 (7) ◽

pp. 1814

Author(s):

Plinio Mendes Senna ◽

Carlos Fernando de Almeida Barros Mourão ◽

Rafael Coutinho Mello-Machado ◽

Kayvon Javid ◽

Pietro Montemezzi ◽

...

Keyword(s):

Bone Formation ◽

Photoelectron Spectroscopy ◽

Titanium Surface ◽

Rabbit Model ◽

Biologically Active ◽

Force Microscopy ◽

Atomic Force ◽

Silane Coating ◽

Titanium Screws

Silane-coating strategy has been used to bind biological compounds to the titanium surface, thereby making implant devices biologically active. However, it has not been determined if the presence of the silane coating itself is biocompatible to osseointegration. The aim of the present study was to evaluate if silane-coating affects bone formation on titanium using a rabbit model. For this, titanium screw implants (3.75 by 6 mm) were hydroxylated in a solution of H2SO4/30% H2O2 for 4 h before silane-coating with 3-aminopropyltriethoxysilane (APTES). A parallel set of titanium screws underwent only the hydroxylation process to present similar acid-etched topography as a control. The presence of the silane on the surface was checked by x-ray photoelectron spectroscopy (XPS), with scanning electron microscopy (SEM) and atomic force microscopy (AFM). A total of 40 titanium screws were implanted in the tibia of ten New Zealand rabbits in order to evaluate bone-to-implant contact (BIC) after 3 weeks and 6 weeks of healing. Silane-coated surface presented higher nitrogen content in the XPS analysis, while micro- and nano-topography of the surface remained unaffected. No difference between the groups was observed after 3 and 6 weeks of healing (p > 0.05, independent t-test), although an increase in BIC occurred over time. These results indicate that silanization of a titanium surface with APTES did not impair the bone formation, indicating that this can be a reliable tool to anchor osteogenic molecules on the surface of implant devices.

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