Biomimetic antifouling PDMS surface developed via well-defined polymer brushes for cardiovascular applications

ABSTRACTFor biological and mechanical systems involving moving parts, surface slipperiness is often a critical attribute for their optimal functions. Surface grafting with hydrophilic polymers is a powerful means to render materials slippery in aqueous environment. In “inverted grafting-to approach”, the hydrophilic polymer chains of amphiphilic diblock copolymers dispersed within a poly(dimethylsiloxane) (PDMS) network are selectively segregated upon exposure to aqueous solution. This allows formation of extremely stable brush-like polymer layers. Tribological application of inverted grafting-to approach was successfully demonstrated with PDMS-block-poly(acrylic acid) (PDMS-b-PAA) dispersed within thin PDMS films on PDMS blocks by showing friction coefficients (µ) of ca 10-2 to 10-3, depending on the load, pH and buffer salinity in the absence of other external re-supply of PAA chains. Further manipulations of the thin PDMS film incorporating PDMS-b-PAA to optimize the tribological properties are presented. Lastly, first trials to employ PAA-grafted PDMS surface to generate in-vitro mucosae model are also presented and discussed.

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Forces between asymmetric polymer brushes

Journal de Physique ◽

10.1051/jphys:01990005108070100 ◽

1990 ◽

Vol 51 (8) ◽

pp. 701-707 ◽

Cited By ~ 8

Author(s):

D.F.K. Shim ◽

M. E. Cates

Keyword(s):

Polymer Brushes

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Nanostructured Polymer Brushes With Reversibly Changing Properties

MRS Proceedings ◽

10.1557/proc-727-r2.5 ◽

2002 ◽

Vol 727 ◽

Author(s):

Denys Usov ◽

Manfred Stamm ◽

Sergiy Minko ◽

Christian Froeck ◽

Andreas Scholl ◽

...

Keyword(s):

Polymer Brushes ◽

Phase Segregation ◽

Water Contact ◽

Angle Measurements ◽

Nanostructured Polymer ◽

Contact Angle Measurements ◽

Vertical Segregation ◽

Oxygen Plasma Etching ◽

Grafting From ◽

Photoemission Electron

AbstractWe investigated the interplay between different mechanisms of the lateral and vertical segregation in the synthesized via “grafting from” approach symmetric A/B (where A and B are poly(styrene-co-2,3,4,5,6-pentafluorostyrene) and poly(methylmethacrylate), respectively) polymer brushes upon exposure to different solvents. We used X-ray photoemission electron spectroscopy and microscopy (X-PEEM), AFM, water contact angle measurements, and oxygen plasma etching to study morphology of the brushes. The ripple morphology after toluene (nonselective solvent) revealed elongated lamellar-like domains of A and B polymers alternating across the surface. The dimple-A morphology consisting of round clusters of the polymer A was observed after acetone (selective solvent for B). The top layer was enriched with the polymer B showing that the brush underwent both the lateral and vertical phase segregation. A qualitative agreement with predictions of SCF theory was found.

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Multi-Stimuli-Responsive Mesoporous Membranes and Effect of Molecular Architecture on Thermo- and pH-Responsive Behavior of the grafted Block Copolymer brushes

10.26434/chemrxiv.7037699 ◽

2019 ◽

Author(s):

Yanchun Tang ◽

Kohzo Ito ◽

Hideaki Yokoyama

Keyword(s):

Polymer Brushes ◽

Diblock Copolymers ◽

Neutron Reflectivity ◽

Molecular Architecture ◽

Stimuli Responsive ◽

Responsive Polymer ◽

The Matrix ◽

Stable Part ◽

Copolymer Brushes ◽

Mesoporous Membranes

In this study, we prepared ultrafiltration membranes with a decoupled responses of filtration property to temperature and pH. The membrane preparation method was developed based on our previous work. We utilized methanol-supercritical carbon dioxide (methanol-scCO2) selective swelling method to introduce nanopores to block copolymers containing poly(diethylene glycol) methyl ether methacrylate (PMEO2MA), poly(N,N-dimethylaminoethyl methacrylate) (PDMAEMA) and polystyrene (PS) blocks. Formation of the mesoporous barrier layer with PS being the mechanically stable part of the matrix was driven by selective swelling of the PMEO2MA-b-PDMAEMA domains. Due to the selective swelling of PMEO2MA or PDMAEMA domains to introduce pores, the interior of the pores are covered with PMEO2MA or PDMAEMA blocks after pore formation. The PMEO2MA-b-PDMAEMA polymer brushes are naturally attached on the pore walls and worked as functional gates. PMEO2MA is a non-toxic, neutral thermo-responsive polymer with LCST at 26 ᴼC. PDMAEMA is a typical weak polyelectrolyte with pKa value at 7.0-7.5 and also a thermo-responsive polymer revealed a LCST of 20-80 °C in aqueous solution. Therefore, these membranes were expected to have multi dimensions as function of the combination of temperature and pH. Moreover, to understand the detail of the temperature and pH depended conformation transitions of PMEO2MA-b-PDMAEMA brushes, those diblock copolymers were end-tethered on flat substrates and analyzed via neutron reflectivity (NR).

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Self-regenerating giant hyaluronan polymer brushes

Nature Communications ◽

10.1038/s41467-019-13440-7 ◽

2019 ◽

Vol 10 (1) ◽

Cited By ~ 5

Author(s):

Wenbin Wei ◽

Jessica L. Faubel ◽

Hemaa Selvakumar ◽

Daniel T. Kovari ◽

Joanna Tsao ◽

...

Keyword(s):

Wound Healing ◽

Polymer Brushes ◽

Functional Materials ◽

Polymer Physics ◽

High Density ◽

Hyaluronan Synthase ◽

Dynamic Interface ◽

Continuous Source

AbstractTailoring interfaces with polymer brushes is a commonly used strategy to create functional materials for numerous applications. Existing methods are limited in brush thickness, the ability to generate high-density brushes of biopolymers, and the potential for regeneration. Here we introduce a scheme to synthesize ultra-thick regenerating hyaluronan polymer brushes using hyaluronan synthase. The platform provides a dynamic interface with tunable brush heights that extend up to 20 microns – two orders of magnitude thicker than standard brushes. The brushes are easily sculpted into micropatterned landscapes by photo-deactivation of the enzyme. Further, they provide a continuous source of megadalton hyaluronan or they can be covalently-stabilized to the surface. Stabilized brushes exhibit superb resistance to biofilms, yet are locally digested by fibroblasts. This brush technology provides opportunities in a range of arenas including regenerating tailorable biointerfaces for implants, wound healing or lubrication as well as fundamental studies of the glycocalyx and polymer physics.

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Antifouling and Flux Enhancement of Reverse Osmosis Membrane by Grafting Poly (3-Sulfopropyl Methacrylate) Brushes

Membranes ◽

10.3390/membranes11030213 ◽

2021 ◽

Vol 11 (3) ◽

pp. 213

Author(s):

Reema Mushtaq ◽

Muhammad Asad Abbas ◽

Shehla Mushtaq ◽

Nasir M. Ahmad ◽

Niaz Ali Khan ◽

...

Keyword(s):

Contact Angle ◽

Reverse Osmosis ◽

Polymer Brushes ◽

Surface Composition ◽

Reverse Osmosis Membrane ◽

Optical Profilometry ◽

Thin Film Composite ◽

Membrane Sample ◽

Contact Angle Analysis ◽

And Staphylococcus Aureus

A commercial thin film composite (TFC) polyamide (PA) reverse osmosis membrane was grafted with 3-sulfopropyl methacrylate potassium (SPMK) to produce PA-g-SPMK by atom transfer radical polymerization (ATRP). The grafting of PA was done at varied concentrations of SPMK, and its effect on the surface composition and morphology was studied by Fourier-Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), optical profilometry, and contact angle analysis. The grafting of hydrophilic ionically charged PSPMK polymer brushes having acrylate and sulfonate groups resulted in enhanced hydrophilicity rendering a reduction of contact angle from 58° of pristine membrane sample labeled as MH0 to 10° for a modified membrane sample labeled as MH3. Due to the increased hydrophilicity, the flux rate rises from 57.1 L m−2 h−1 to 71.2 L m−2 h−1, and 99% resistance against microbial adhesion (Escherichia coli and Staphylococcus aureus) was obtained for MH3 after modification

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Layer by layer assembled functionalized graphene oxide-based polymer brushes for superlubricity on steel-steel tribocontact

Soft Matter ◽

10.1039/d1sm00690h ◽

2021 ◽

Author(s):

Suprakash Samanta ◽

Rashmi Ranjan Sahoo

Keyword(s):

Graphene Oxide ◽

Nucleophilic Addition ◽

Polymer Brushes ◽

Addition Reaction ◽

Layer By Layer ◽

Functionalized Graphene ◽

Covalent Functionalization ◽

Functionalized Graphene Oxide ◽

Nucleophilic Addition Reaction ◽

Branched Polyethylenimine

Present study demonstrates a simple and multistep approach for the preparation of covalent functionalization of chemically prepared graphene oxide (GO) by branched polyethylenimine (PEI) through nucleophilic addition reaction to prepare...

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FRET‐Integrated Polymer Brushes for Spatially‐Resolved Sensing of Changes in Polymer Conformation

Angewandte Chemie ◽

10.1002/ange.202104204 ◽

2021 ◽

Author(s):

Quinn Alexander Besford ◽

Huaisong Yong ◽

Holger Merlitz ◽

Andrew J. Christofferson ◽

Jens-Uwe Sommer ◽

...

Keyword(s):

Polymer Brushes ◽

Polymer Conformation ◽

Spatially Resolved

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Alcohol-based highly conductive polymer for conformal nanocoatings on hydrophobic surfaces toward a highly sensitive and stable pressure sensor

NPG Asia Materials ◽

10.1038/s41427-020-00238-z ◽

2020 ◽

Vol 12 (1) ◽

Cited By ~ 1

Author(s):

Jung Joon Lee ◽

Srinivas Gandla ◽

Byeongjae Lim ◽

Sunju Kang ◽

Sunyoung Kim ◽

...

Keyword(s):

Pressure Sensor ◽

Mechanical Stability ◽

Exchange Process ◽

Conductive Polymer ◽

High Sensitivity ◽

Fast Response ◽

Pdms Surface ◽

Practical Applications ◽

Sensor Applications ◽

Water Based

Abstract Conformal and ultrathin coating of highly conductive PEDOT:PSS on hydrophobic uneven surfaces is essential for resistive-based pressure sensor applications. For this purpose, a water-based poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) solution was successfully exchanged to an organic solvent-based PEDOT:PSS solution without any aggregation or reduction in conductivity using the ultrafiltration method. Among various solvents, the ethanol (EtOH) solvent-exchanged PEDOT:PSS solution exhibited a contact angle of 34.67°, which is much lower than the value of 96.94° for the water-based PEDOT:PSS solution. The optimized EtOH-based PEDOT:PSS solution exhibited conformal and uniform coating, with ultrathin nanocoated films obtained on a hydrophobic pyramid polydimethylsiloxane (PDMS) surface. The fabricated pressure sensor showed high performances, such as high sensitivity (−21 kPa−1 in the low pressure regime up to 100 Pa), mechanical stability (over 10,000 cycles without any failure or cracks) and a fast response time (90 ms). Finally, the proposed pressure sensor was successfully demonstrated as a human blood pulse rate sensor and a spatial pressure sensor array for practical applications. The solvent exchange process using ultrafiltration for these applications can be utilized as a universal technique for improving the coating property (wettability) of conducting polymers as well as various other materials.

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Universal Plasma Jet for Droplet Manipulation on a PDMS Surface towards Wall-Less Scaffolds

Polymers ◽

10.3390/polym13081321 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1321

Author(s):

Cheng-Yun Peng ◽

Chia-Hung Dylan Tsai

Keyword(s):

Plasma Treatment ◽

Treatment Time ◽

Plasma Jet ◽

Aging Effect ◽

Droplet Generation ◽

Magnetic Actuation ◽

Pdms Surface ◽

Polymeric Surface ◽

Air Jet ◽

Droplet Manipulation

Droplet manipulation is important in the fields of engineering, biology, chemistry, and medicine. Many techniques, such as electrowetting and magnetic actuation, have been developed for droplet manipulation. However, the fabrication of the manipulation platform often takes a long time and requires well-trained skills. Here we proposed a novel method that can directly generate and manipulate droplets on a polymeric surface using a universal plasma jet. One of its greatest advantages is that the jet can tremendously reduce the time for the platform fabrication while it can still perform stable droplet manipulation with controllable droplet size and motion. There are two steps for the proposed method. First, the universal plasma jet is set in plasma mode for modifying the manipulation path for droplets. Second, the jet is switched to air-jet mode for droplet generation and manipulation. The jetted air separates and pushes droplets along the plasma-treated path for droplet generation and manipulation. According to the experimental results, the size of the droplet can be controlled by the treatment time in the first step, i.e., a shorter treatment time of plasma results in a smaller size of the droplet, and vice versa. The largest and the smallest sizes of the generated droplets in the results are about 6 µL and 0.1 µL, respectively. Infrared spectra of absorption on the PDMS surfaces with and without the plasma treatment are investigated by Fourier-transform infrared spectroscopy. Tests of generating and mixing two droplets on a PDMS surface are successfully achieved. The aging effect of plasma treatment for the proposed method is also discussed. The proposed method provides a simple, fast, and low-cost way to generate and manipulate droplets on a polymeric surface. The method is expected to be applied to droplet-based cell culture by manipulating droplets encapsulating living cells and towards wall-less scaffolds on a polymeric surface.

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