Improving the biocompatibility of poly(ε-caprolactone) by surface Immobilization of chitosan and heparin

e-Polymers ◽  
2008 ◽  
Vol 8 (1) ◽  
Author(s):  
Wei Zhong ◽  
Zongjun Liu ◽  
Piotr Tomasik ◽  
Huigen Jin ◽  
Nianjian Lv ◽  
...  
Keyword(s):  
Self Assembly ◽  
Anticoagulant Activity ◽  
Surface Immobilization ◽  
Angle Measurements ◽  
Lbl Assembly ◽  
Static Contact ◽  
Contact Angle Measurements ◽  
Assembly Procedure ◽  
Surface Modified ◽  
Positively Charged

AbstractOppositely charged natural polyelectrolyte Heparin (HS) and chitosan (CS) were immobilized on the surface of poly(ε-caprolactone) (PCL) by a layer-bylayer (LBL) self-assembly procedure. Positively charged poly(allylamine hydrochloride) (PAH) was used as the first layer onto the surface of PCL. Then negatively charged HS and positively charged CS were deposited in a LBL assembly manner. The effect of this surface modification method was evaluated by ATR-FTIR spectroscopy and static contact angle measurements. The anticoagulant activity of modified PCL was evaluated using full human blood. The modified PCL samples showed prolonged activated partial thromboplastin time (APTT), prothrombin time (PT) and thromboplastin time (TT) compared with neat PCL. Scanning electron microscopy (SEM) indicated that adhered platelets retained their natural, round morphology on the modified PCL surface. The cytocompatibility of the HS/CS surface modified PCL sample was evaluated with pig iliac arteries endothelial cells (PIECs). The proliferation of the cells cultured on modified PCL films was better than those on neat PCL films.

scholarly journals Synthesis, Hydrophilicity and Micellization of Coil–Brush Polystyrene-b-(polyglycidol-g-polyglycidol) Copolymer—Comparison with Linear Polystyrene-b-Polyglycidol

Polymers ◽  
2022 ◽  
Vol 14 (2) ◽  
pp. 253
Author(s):  
Mariusz Gadzinowski ◽  
Maciej Kasprów ◽  
Teresa Basinska ◽  
Stanislaw Slomkowski ◽  
Łukasz Otulakowski ◽  
...  
Keyword(s):  
Contact Angle ◽  
Self Assembly ◽  
Original Method ◽  
Critical Micellization Concentration ◽  
Water Contact ◽  
1H And 13C Nmr ◽  
Similar Composition ◽  
Angle Measurements ◽  
Contact Angle Measurements ◽  
Static Conditions

In this paper, an original method of synthesis of coil–brush amphiphilic polystyrene-b-(polyglycidol-g-polyglycidol) (PS-b-(PGL-g-PGL)) block copolymers was developed. The hypothesis that their hydrophilicity and micellization can be controlled by polyglycidol blocks architecture was verified. The research enabled comparison of behavior in water of PS-b-PGL copolymers and block–brush copolymers PS-b-(PGL-g-PGL) with similar composition. The coil–brush copolymers were composed of PS-b-PGL linear core with average DPn of polystyrene 29 and 13 of polyglycidol blocks. The DPn of polyglycidol side blocks of coil–b–brush copolymers were 2, 7, and 11, respectively. The copolymers were characterized by 1H and 13C NMR, GPC, and FTIR methods. The hydrophilicity of films from the linear and coil–brush copolymers was determined by water contact angle measurements in static conditions. The behavior of coil–brush copolymers in water and their critical micellization concentration (CMC) were determined by UV-VIS using 1,6-diphenylhexa-1,3,5-trien (DPH) as marker and by DLS. The CMC values for brush copolymers were much higher than for linear species with similar PGL content. The results of the copolymer film wettability and the copolymer self-assembly studies were related to fraction of hydrophilic polyglycidol. The CMC for both types of polymers increased exponentially with increasing content of polyglycidol.

scholarly journals Precise Static Contact Angle Measurements Using Pythagolas Rule

2014 ◽  
Vol 15 (2) ◽  
pp. 57-62
Author(s):  
Jin-Yeong Choi ◽  
Dong-Jun Kwon ◽  
Zuo-Jia Wang ◽  
Pyeong-Su Shin ◽  
Joung-Man Park
Keyword(s):  
Contact Angle ◽  
Static Contact Angle ◽  
Angle Measurements ◽  
Static Contact ◽  
Contact Angle Measurements

Zwitterionic molecule layer for inhibiting microbial corrosion of copper alloy

2018 ◽  
Vol 65 (1) ◽  
pp. 46-52
Author(s):  
Fengling Xu ◽  
Zhenghui Qiu ◽  
Ri Qiu ◽  
Jiadong Yang ◽  
Cunguo Lin
Keyword(s):  
Electrochemical Impedance ◽  
Chemical Vapor ◽  
Attenuated Total Reflectance ◽  
Microbial Corrosion ◽  
Content Type ◽  
Sulfate Reducing ◽  
Angle Measurements ◽  
Static Contact ◽  
Contact Angle Measurements ◽  
Reducing Bacteria

Purpose For mitigating biocorrosion induced by sulfate-reducing bacteria (SRB) in seawater, the zwitterionic molecule layer (ZML) of poly (sulfobetaine methacrylate) is grafted onto B10 surface by chemical vapor deposition and surface-initiated atom transfer radical polymerization. Design/methodology/approach Energy-dispersive spectroscopy-attenuated total reflectance Fourier transform infrared spectroscopy and static contact angle measurements are used to characterize the as-formed layer. Findings After surface modification, B10 can significantly reduce SRB adhesion, demonstrating the good antifouling property. Further, the biocorrosion inhibition is investigated by potentiodynamic polarization and electrochemical impedance spectroscopy, indicating that ZML exhibits high resistance to biocorrosion with inhibition efficiency of approximately 90 per cent. Originality/value ZML performs a dual feature, i.e. antifouling film and corrosion inhibitor, for the biocorrosion inhibition.

Surface-modified halloysite nanotubes as fillers applied in reinforcing the performance of polytetrafluoroethylene

Clay Minerals ◽  
2018 ◽  
Vol 53 (4) ◽  
pp. 643-656 ◽  
Author(s):  
Zhi-Lin Cheng ◽  
Xing-Yu Chang ◽  
Zan Liu ◽  
Dun-Zhong Qin
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Sodium Dodecyl ◽  
Halloysite Nanotubes ◽  
Angle Measurements ◽  
Transmission Electron ◽  
Contact Angle Measurements ◽  
Ftir Spectrometry ◽  
Surface Modified ◽  
Scanning Electron

ABSTRACTIn order to improve the dispersibility of halloysite nanotubes (HNTs) in polytetrafluoroethylene (PTFE), the modification of HNT surfaces was studied with three types of modifiers (polymethyl methacrylate [PMMA], sodium dodecyl sulfate [SDS] and carboxylic acid). The modified HNTs were characterized by Fourier-transform infrared (FTIR) spectrometry, transmission electron microscopy (TEM), scanning electron microscopy (SEM) and contact angle measurements. The HNTs were used to reinforce the mechanical properties of PTFE. The mechanical results indicated that the tensile strength of the modified HNT-filled PTFE nanocomposites (F-HNT/PTFE) improved to an acceptable degree and Young's modulus increased significantly. The tribological results showed that the wear rate of F-HNT/PTFE decreased by 21–82 and 9–40 times compared to pure PTFE and the pristine F-HNT/PTFE, respectively.

Vertically aligned CNT arrays: structural integrity and surface properties

2016 ◽  
Vol 7 (6) ◽  
pp. 703-711 ◽  
Author(s):  
Dimitris K. Perivoliotis ◽  
Malamatenia A. Koklioti ◽  
Elias P. Koumoulos ◽  
Yiannis S. Raptis ◽  
Costas A. Charitidis
Keyword(s):  
Contact Angle ◽  
Structural Integrity ◽  
Mechanical Performance ◽  
Content Type ◽  
Cvd Method ◽  
Angle Measurements ◽  
Hydrophobic Behavior ◽  
Static Contact ◽  
Contact Angle Measurements ◽  
Cnt Arrays

Purpose Carbon nanotube-based architectures have increased the scientific interest owning to their exceptional performance rendering them promising candidates for advanced industrial applications in the nanotechnology field. Despite individual CNTs being considered as one of the most known strong materials, much less is known about other CNT forms, such as CNT arrays, in terms of their mechanical performance. The paper aims to discuss these issues. Design/methodology/approach In this work, thermal CVD method is employed to produce VA-MWCNT carpets. Their structural properties were studied by means of SEM, XRD and Raman spectroscopy, while their hydrophobic behavior was investigated via contact angle measurements. The resistance to indentation deformation of VA-MWCNT carpets was investigated through nanoindentation technique. Findings The synthesized VA-MWCNTs carpets consisted of well-aligned MWCNTs. Static contact angle measurements were performed with water and glycerol, revealing a rather super-hydrophobic behavior. Originality/value The structural analysis, hydrophobic behavior and indentation response of VA-MWCNTs carpets synthesized via CVD method are clearly demonstrated.

scholarly journals Specific ion modulated thermoresponse of poly(N-isopropylacrylamide) brushes

2016 ◽  
Vol 18 (8) ◽  
pp. 6037-6046 ◽  
Author(s):  
Ben A. Humphreys ◽  
Joshua D. Willott ◽  
Timothy J. Murdoch ◽  
Grant B. Webber ◽  
Erica J. Wanless
Keyword(s):  
Contact Angle ◽  
Static Contact Angle ◽  
Angle Measurements ◽  
Static Contact ◽  
Contact Angle Measurements

Specific anion identity and concentration dictates the direction and magnitude of the shift in LCST for a pNIPAM brush determined by in situ ellipsometry, QCM-D and static contact angle measurements.

scholarly journals A Facile Activation Method for Improving the Wettability of Polyurethane Surfaces

2019 ◽  
Vol 56 (2) ◽  
pp. 416-420
Author(s):  
Luiza Madalina Gradinaru ◽  
Stelian Vlad ◽  
Mioara Drobota ◽  
Maria Spiridon ◽  
Ioan Istrate
Keyword(s):  
Contact Angle ◽  
Polymer Surface ◽  
Bulk Properties ◽  
Polar Interaction ◽  
Polar Groups ◽  
Angle Measurements ◽  
Static Contact ◽  
Contact Angle Measurements ◽  
Polyurethane Film ◽  
Time Periods

This work reports the activation of polyurethane film surfaces in order to enrich them with polar groups such as -NH2, -OH, -COOH or radicals, which further allows immobilization of several bioactive compounds. UV-activation was used to introduce new groups on the polymer surface without affecting the bulk properties. The current arising species improve the wettability of the PU surfaces as it was observed from the static contact angle measurements. The structure and composition of the new PU surfaces were analyzed by using ATR-FTIR spectroscopy. The results suggested the possibility of modifying the PU surfaces in a shorter time periods, in order to provide many sites to attach other biomacromolecules by polar interaction or hydrogen bonding.

scholarly journals A Comparison of Commercial and Experimental Ultrafiltration Membranes via Surface Property Analysis and Fouling Tests

2006 ◽  
Vol 41 (1) ◽  
pp. 84-93 ◽  
Author(s):  
Huyen T. Dang ◽  
Roberto M. Narbaitz ◽  
Takeshi Matsuura ◽  
Kailash C. Khulbe
Keyword(s):  
Ultrafiltration Membranes ◽  
Force Microscopy ◽  
Ottawa River ◽  
Angle Measurements ◽  
Atomic Force ◽  
Molecular Weight Cutoff ◽  
Contact Angle Measurements ◽  
Different Types ◽  
Transport Analysis ◽  
Surface Modified

Abstract Surface modified polyethersulfone (PES) membranes via the addition of different hydrophiLic Surface Modifying Macromolecules (LSMMs) have been developed by Matsuura, Narbaitz and co-workers. This study compares the performance of the best PES-LSMM membrane with nine commercial ultrafiltration membranes manufactured using five different types of base polymers (polyethersulfone, polysulfone, celluloseacetate, polyacrylonitrile and cellulose) in the same range of molecular weight cutoff (MWCO) (from 40 to 120 kDal). All membranes were characterized by using atomic force microscopy, contact angle measurements, solute transport analysis and then evaluated through fouling tests with Ottawa River water (ORW). While PES-LSMM membranes had much lower initial flux than the commercial membranes, they had the highest total organic carbon (TOC) rejection (80%) and the lowest flux reduction (62%). For the commercial membranes, the range of TOC rejections and flux reductions were 62 to 80% and 68 to 80%, respectively. Given their high TOC rejection and relatively high foulant deposition, fouling of the PES-LSMM membranes appears to be controlled by a surface gel.

scholarly journals Tuning friction and slip at solid-nanoparticle suspension interfaces by electric fields

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
B. Acharya ◽  
C. M. Seed ◽  
D. W. Brenner ◽  
A. I. Smirnov ◽  
J. Krim
Keyword(s):  
Electric Fields ◽  
Interfacial Friction ◽  
Theoretical Frameworks ◽  
Nanoparticle Suspension ◽  
External Electric Fields ◽  
Angle Measurements ◽  
Platinum Surfaces ◽  
Contact Angle Measurements ◽  
Water Layers ◽  
Positively Charged

AbstractWe report an experimental Quartz Crystal Microbalance (QCM) study of tuning interfacial friction and slip lengths for aqueous suspensions of TiO2 and Al2O3 nanoparticles on planar platinum surfaces by external electric fields. Data were analyzed within theoretical frameworks that incorporate slippage at the QCM surface electrode or alternatively at the surface of adsorbed particles, yielding values for the slip lengths between 0 and 30 nm. Measurements were performed for negatively charged TiO2 and positively charged Al2O3 nanoparticles in both the absence and presence of external electric fields. Without the field the slip lengths inferred for the TiO2 suspensions were higher than those for the Al2O3 suspensions, a result that was consistent with contact angle measurements also performed on the samples. Attraction and retraction of particles perpendicular to the surface by means of an externally applied field resulted in increased and decreased interfacial friction levels and slip lengths. The variation was observed to be non-monotonic, with a profile attributed to the physical properties of interstitial water layers present between the nanoparticles and the platinum substrate.

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