The Experts below are selected from a list of 17562 Experts worldwide ranked by ideXlab platform
Johannes S. Vrouwenvelder - One of the best experts on this subject based on the ideXlab platform.
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short term adhesion and long term biofouling testing of Polydopamine and poly ethylene glycol surface modifications of membranes and feed spacers for biofouling control
Water Research, 2012Co-Authors: Daniel J Miller, Joop C. Kruithof, Benny D. Freeman, Paula Araujo, Patricia Correia, Matthew Ramsey, Mark C M Van Loosdrecht, Donald R Paul, Marvin Whiteley, Johannes S. VrouwenvelderAbstract:Abstract Ultrafiltration, nanofiltration membranes and feed spacers were hydrophilized with Polydopamine and Polydopamine- g -poly(ethylene glycol) surface coatings. The fouling propensity of modified and unmodified membranes was evaluated by short-term batch protein and bacterial adhesion tests. The fouling propensity of modified and unmodified membranes and spacers was evaluated by continuous biofouling experiments in a membrane fouling simulator. The goals of the study were: 1) to determine the effectiveness of Polydopamine and Polydopamine- g -poly(ethylene glycol) membrane coatings for biofouling control and 2) to compare techniques commonly used in assessment of membrane biofouling propensity with biofouling experiments under practical conditions. Short-term adhesion tests were carried out under static, no-flow conditions for 1 h using bovine serum albumin, a common model globular protein, and Pseudomonas aeruginosa , a common model Gram-negative bacterium. Biofouling tests were performed in a membrane fouling simulator (MFS) for several days under flow conditions similar to those encountered in industrial modules with the autochthonous drinking water population and acetate dosage as organic substrate. Polydopamine- and Polydopamine- g -poly(ethylene glycol)-modified membranes showed significantly reduced adhesion of bovine serum albumin and P. aeruginosa in the short-term adhesion tests, but no reduction of biofouling was observed during longer biofouling experiments with modified membranes and spacers. These results demonstrate that short-term batch adhesion experiments using model proteins or bacteria under static conditions are not indicative of biofouling, while continuous biofouling experiments showed that membrane surface modification by Polydopamine and Polydopamine- g -poly(ethylene glycol) is not effective for biofouling control.
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impact of feed spacer and membrane modification by hydrophilic bactericidal and biocidal coating on biofouling control
Desalination, 2012Co-Authors: Paula Araujo, Johannes S. Vrouwenvelder, Daniel J Miller, Benny D. Freeman, Patricia Correia, Donald R Paul, M C M Van Loosdrecht, J C KruithofAbstract:Abstract The influence of Polydopamine- and Polydopamine- graft -poly(ethylene glycol)-coated feed spacers and membranes, copper-coated feed spacers, and commercially-available biostatic feed spacers on biofouling has been studied in membrane fouling simulators. Feed spacers and membranes applied in practical membrane filtration systems were used; biofouling development was monitored by feed channel pressure drop increase and biomass accumulation. Polydopamine and Polydopamine- g -PEG are hydrophilic surface modification agents expected to resist protein and bacterial adhesion, while copper feed spacer coatings and biocides infused in feed spacers are expected to restrict biological growth. Our studies showed that Polydopamine and Polydopamine- g -PEG coatings on feed spacers and membranes, copper coatings on feed spacers, and a commercial biostatic feed spacer did not have a significant impact on feed channel pressure drop increase and biofilm accumulation as measured by ATP and TOC content. The studied spacer and membrane modifications were not effective for biofouling control; it is doubtful that feed spacer and membrane modification, in general, may be effective for biofouling control regardless of the type of applied coating.
Wen-xin Mao - One of the best experts on this subject based on the ideXlab platform.
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core shell structured tio2 Polydopamine for highly active visible light photocatalysis
Chemical Communications, 2016Co-Authors: Wen-xin Mao, Xi-jie Lin, Wei Zhang, Zi-xiang Chi, Rong-wen Lyu, An-min Cao, Li-jun WanAbstract:This communication reports that the TiO2@Polydopamine nanocomposite with a core–shell structure could be a highly active photocatalyst working under visible light. A very thin layer of Polydopamine at around 1 nm was found to be critical for the degradation of Rhodamine B.
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Core-shell structured TiO2@Polydopamine for highly active visible-light photocatalysis.
Chemical communications (Cambridge England), 2016Co-Authors: Wen-xin Mao, Xi-jie Lin, Wei Zhang, Zi-xiang Chi, Rong-wen Lyu, An-min Cao, Li-jun WanAbstract:This communication reports that the TiO2@Polydopamine nanocomposite with a core–shell structure could be a highly active photocatalyst working under visible light. A very thin layer of Polydopamine at around 1 nm was found to be critical for the degradation of Rhodamine B.
Li-jun Wan - One of the best experts on this subject based on the ideXlab platform.
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core shell structured tio2 Polydopamine for highly active visible light photocatalysis
Chemical Communications, 2016Co-Authors: Wen-xin Mao, Xi-jie Lin, Wei Zhang, Zi-xiang Chi, Rong-wen Lyu, An-min Cao, Li-jun WanAbstract:This communication reports that the TiO2@Polydopamine nanocomposite with a core–shell structure could be a highly active photocatalyst working under visible light. A very thin layer of Polydopamine at around 1 nm was found to be critical for the degradation of Rhodamine B.
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Core-shell structured TiO2@Polydopamine for highly active visible-light photocatalysis.
Chemical communications (Cambridge England), 2016Co-Authors: Wen-xin Mao, Xi-jie Lin, Wei Zhang, Zi-xiang Chi, Rong-wen Lyu, An-min Cao, Li-jun WanAbstract:This communication reports that the TiO2@Polydopamine nanocomposite with a core–shell structure could be a highly active photocatalyst working under visible light. A very thin layer of Polydopamine at around 1 nm was found to be critical for the degradation of Rhodamine B.
Vincent Ball - One of the best experts on this subject based on the ideXlab platform.
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Polydopamine/Transferrin Hybrid Nanoparticles for Targeted Cell-Killing
Nanomaterials (Basel Switzerland), 2018Co-Authors: Daniel Hauser, Vincent Ball, Manuela Estermann, Ana Milosevic, Lukas Steinmetz, Dimitri Vanhecke, Dedy Septiadi, Barbara Drasler, Alke Petri-fink, Barbara Rothen-rutishauserAbstract:Polydopamine can form biocompatible particles that convert light into heat. Recently, a protocol has been optimized to synthesize Polydopamine/protein hybrid nanoparticles that retain the biological function of proteins, and combine it with the stimuli-induced heat generation of Polydopamine. We have utilized this novel system to form Polydopamine particles, containing transferrin (PDA/Tf). Mouse melanoma cells, which strongly express the transferrin receptor, were exposed to PDA/Tf nanoparticles (NPs) and, subsequently, were irradiated with a UV laser. The cell death rate was monitored in real-time. When irradiated, the melanoma cells exposed to PDA/Tf NPs underwent apoptosis, faster than the control cells, pointing towards the ability of PDA/Tf to mediate UV-light-induced cell death. The system was also validated in an organotypic, 3D-printed tumor spheroid model, comprising mouse melanoma cells, and the exposure and subsequent irradiation with UV-light, yielded similar results to the 2D cell culture. The process of apoptosis was found to be targeted and mediated by the lysosomal membrane permeabilization. Therefore, the herein presented Polydopamine/protein NPs constitute a versatile and stable system for cancer cell-targeting and photothermal apoptosis induction.
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role of surfactants in the control of dopamine eumelanin particle size and in the inhibition of film deposition at solid liquid interfaces
Journal of Colloid and Interface Science, 2014Co-Authors: Philippe Bertani, Florian Ponzio, Vincent BallAbstract:Abstract Anionic and cationic surfactants such as sodium dodecylsulfate (SDS) and hexadecyltrimethylammonium bromide (HTAB) are able to control the size of “Polydopamine” particles produced from dopamine solutions and to simultaneously strongly inhibit the deposition of “Polydopamine” on surfaces. Indeed, dynamic light scattering experiments allowed to show that the hydrodynamic radius of Polydopamine progressively decreases from about 1 μm to a few nanometer upon an increase in the SDS and CTAB concentration. At the highest surfactant concentration used (50 mM) the size of the aggregates is only slightly larger than the size of the surfactant micelles. On the other hand, the non-ionic Triton X-100 surfactant has no significant influence on both phenomena. It is suggested that the observed effect originates from the anionic and cationic surfactants acting as a template in which the growth of “Polydopamine” is confined.
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Activity of alkaline phosphatase adsorbed and grafted on "Polydopamine" films.
Journal of colloid and interface science, 2014Co-Authors: Vincent BallAbstract:Abstract The oxidation of dopamine in slightly basic solutions and in the presence of oxygen as an oxidant allows for the deposition of dopamine–eumelanin (“Polydopamine”) films on almost all kinds of materials allowing for an easy secondary functionalization. Molecules carrying nucleophilic groups like thiols and amines can be easily grafted on those films. Herein we show that alkaline phosphatase (ALP), as a model enzyme, adsorbs to “Polydopamine” films and part of the adsorbed enzyme is rapidly desorbed in contact with Tris buffer. However a significant part of the enzyme remains irreversibly adsorbed and keeps some enzymatic activity for at least 2 weeks whereas ALP adsorbed on quartz slides is rapidly and quantitatively deactivated. In addition we estimated the Michaelis constant Km of the enzyme irreversibly bound to the “Polydopamine” film. The Michaelis constant, and hence the affinity constant between paranitrophenol phosphate and ALP are almost identical between the enzyme bound on the film and the free enzyme in solution. Complementarily, it was found that “Polydopamine” films display some phosphatase like catalytic activity.
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Deposition Mechanism and Properties of Thin Polydopamine Films for High Added Value Applications in Surface Science at the Nanoscale
BioNanoScience, 2012Co-Authors: Vincent Ball, Doriane Del Frari, Markus J. Buehler, Valerie Toniazzo, Manoj K Singh, José Joaquin De Almeida Gracio, Marc Michel, David RuchAbstract:Polydopamine films have been introduced by Messersmith eta!. as a possible "versatile" surface function-alization method allowing to coat the surface of almost all known materials even superhydrophobic surfaces. These new kinds of coatings also confer a plethora of functional-ities to the coated materials owing to the complex chemistry of the catechol quinone moieties present on the surfac e of Polydopamine. These coatings may hence become an inter-esting alternative to established surface coatings like self-assembled monolayers and polyelectrolyte multilayered films. In this review, we desc ribe the knowledge acquired in the last 3 years about the deposition mechanisms of Polydopamine films, their properties, and various applications in surface science at the nanoscale.
Xi-jie Lin - One of the best experts on this subject based on the ideXlab platform.
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core shell structured tio2 Polydopamine for highly active visible light photocatalysis
Chemical Communications, 2016Co-Authors: Wen-xin Mao, Xi-jie Lin, Wei Zhang, Zi-xiang Chi, Rong-wen Lyu, An-min Cao, Li-jun WanAbstract:This communication reports that the TiO2@Polydopamine nanocomposite with a core–shell structure could be a highly active photocatalyst working under visible light. A very thin layer of Polydopamine at around 1 nm was found to be critical for the degradation of Rhodamine B.
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Core-shell structured TiO2@Polydopamine for highly active visible-light photocatalysis.
Chemical communications (Cambridge England), 2016Co-Authors: Wen-xin Mao, Xi-jie Lin, Wei Zhang, Zi-xiang Chi, Rong-wen Lyu, An-min Cao, Li-jun WanAbstract:This communication reports that the TiO2@Polydopamine nanocomposite with a core–shell structure could be a highly active photocatalyst working under visible light. A very thin layer of Polydopamine at around 1 nm was found to be critical for the degradation of Rhodamine B.