Development of Rapid Cell Recovery System Using Temperature-Responsive Nanofiber Surfaces

2007 ◽  
Vol 342-343 ◽  
pp. 249-252 ◽  
Author(s):  
Young Gwang Ko ◽  
Hyeon Ae Jeon ◽  
Kwan Han Yoon ◽  
Young Chul Kim ◽  
Chang Hyun Ahn ◽  
...  
Keyword(s):  
Cultured Cells ◽  
Sessile Drop ◽  
Cell Attachment ◽  
Single Cells ◽  
Human Fibroblasts ◽  
Film Surface ◽  
Contact Angles ◽  
Cell Recovery ◽  
Water Contact ◽  
Initial Cell

PHBV ultrafine fibers were fabricated by electrospinning process. Electrospun PHBV fiber structures revealed randomly aligned fibers with average diameter of 400 nm. PIPAAm was grafted on the surface of PHBV nanofibrous mat by electron beam irradiation. PIPAAm-grafted PHBV mats were determined by ATR-FTIR and ESCA. Water contact angles were determined by a sessile drop method at 20 and 37. To examine the tissue compatibility, human fibroblasts were evenly seeded onto PIPAAm-grafted PHBV mat and cast film, ungrafted PHBV mat and film. Attached and spread fibroblasts on nanofibrous mat were proliferated more rapidly than that of flat film surface. Initial cell attachment on PIPAAm-grafted surfaces was higher than ungrafted surfaces. The surface property changed to hydrophilic by PIPAAm graft, which increased initial cell attachment. Detachment of single cells from PIPAAm-grafted PHBV matrixes was measured by low temperature treatment after incubation at 37. Cultured cells were rapidly detached from PIPAAm-grafted PHBV mat compared with film. With porous mats, the water molecules easily reach to grafted PIPAAm from underneath and peripheral to the attached cells, resulting in rapid hydration of grafted PIPAAm molecules and detachment of the cells.

scholarly journals P4VP Modified Zwitterionic Polymer for the Preparation of Antifouling Functionalized Surfaces

Nanomaterials ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 706 ◽  
Author(s):  
Chaoqun Wu ◽  
Yudan Zhou ◽  
Haitao Wang ◽  
Jianhua Hu
Keyword(s):  
Photoelectron Spectroscopy ◽  
Cell Attachment ◽  
Raft Polymerization ◽  
Polymer Brush ◽  
Contact Angles ◽  
Polymerization Process ◽  
Water Contact ◽  
Zwitterionic Polymers ◽  
Ito Glass ◽  
Zwitterionic Polymer

Zwitterionic polymers are suitable for replacing poly(ethylene glycol) (PEG) polymers because of their better antifouling properties, but zwitterionic polymers have poor mechanical properties, strong water absorption, and their homopolymers should not be used directly. To solve these problems, a reversible-addition fragmentation chain transfer (RAFT) polymerization process was used to prepare copolymers comprised of zwitterionic side chains that were attached to an ITO glass substrate using spin-casting. The presence of 4-vinylpyridine (4VP) and zwitterion chains on these polymer-coated ITO surfaces was confirmed using 1H NMR, FTIR, and GPC analyses, with successful surface functionalization confirmed using water contact angle, X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM) studies. Changes in water contact angles and C/O ratios (XPS) analysis demonstrated that the functionalization of these polymers with β-propiolactone resulted in hydrophilic mixed 4VP/zwitterionic polymers. Protein adsorption and cell attachment assays were used to optimize the ratio of the zwitterionic component to maximize the antifouling properties of the polymer brush surface. This work demonstrated that the antifouling surface coatings could be readily prepared using a “P4VP-modified” method, that is, the functionality of P4VP to modify the prepared zwitterionic polymer. We believe these materials are likely to be useful for the preparation of biomaterials for biosensing and diagnostic applications.

PVDF Films with Superhydrophobic Surface Fabricated by Plasma-Enhanced Chemical Vapor Deposition

2009 ◽  
Vol 79-82 ◽  
pp. 1451-1454 ◽  
Author(s):  
Zhi Qiu Zhang ◽  
Wen Fang Yang ◽  
Zhen Ya Gu ◽  
Rui Ting Huo
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Film Surface ◽  
Chemical Vapor ◽  
Contact Angles ◽  
Water Repellent ◽  
Treatment Technology ◽  
Water Contact ◽  
Lotus Effect ◽  
Pvdf Membrane

Lotus effect is well-known to be governed by chemical properties and nanotextures of the surfaces. In this paper, a method with two-steps treatment technology was applied to develop the superhydrophobic polyvinylidene fruoride(PVDF) membrane with the property of anti-contamination and self-cleaning. First, the PVDF membrane was treated by oxygen plasma so as to get the reactive groups. Second, this film was deposited by perfluoroalkylethyl acrylate precursor/Ar gas via plasma-enhanced chemical vapor deposition (PECVD). The modified film surface exhibited ultra water-repellent ability, showing that the water contact angles was larger than 150 °and the dynamic contact angles was usually lower than 5°.

scholarly journals The Effect of Poly(ethylene glycol) (PEG) Length on the Wettability and Surface Chemistry of PEG-Fluoroalkyl-Modified Polystyrene Diblock Copolymers and Their Two-Layer Films with Elastomer Matrix

Polymers ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1236 ◽  
Author(s):  
Elisa Guazzelli ◽  
Giancarlo Galli ◽  
Elisa Martinelli
Keyword(s):  
Diblock Copolymers ◽  
Film Surface ◽  
Dynamic Contact ◽  
Contact Angles ◽  
Side Chains ◽  
Water Contact ◽  
Prolonged Contact ◽  
High Enrichment ◽  
Poly Ethylene ◽  
Modified Polystyrene

Diblock copolymers composed of a polystyrene first block and a PEG-fluoroalkyl chain-modified polystyrene second block were synthesized by controlled atom transfer radical polymerization (ATRP), starting from the same polystyrene macroinitiator. The wettability of the polymer film surfaces was investigated by measurements of static and dynamic contact angles. An increase in advancing water contact angle was evident for all the films after immersion in water for short times (10 and 1000 s), consistent with an unusual contraphilic switch of the PEG-fluoroalkyl side chains. Such a contraphilic response also accounted for the retained wettability of the polymer films upon prolonged contact with water, without an anticipated increase in the hydrophilic character. The copolymers were then used as surface-active modifiers of elastomer poly(styrene-b-(ethylene-co-butylene)-b-styrene) (SEBS)-based two-layer films. The elastomeric behavior of the films was varied by using SEBS matrices with different amounts of polystyrene. Whereas the mechanical properties strictly resembled those of the nature of the SEBS matrix, the surface properties were imposed by the additive. The contraphilic switch of the PEG-fluoroalkyl side chains resulted in an exceptionally high enrichment in fluorine of the film surface after immersion in water for seven days.

scholarly journals Effect of Oxygen Inhibition Layer of Universal Adhesives on Enamel Bond Fatigue Durability and Interfacial Characteristics With Different Etching Modes

2017 ◽  
Vol 42 (6) ◽  
pp. 636-645 ◽  
Author(s):  
H Ouchi ◽  
A Tsujimoto ◽  
K Nojiri ◽  
K Hirai ◽  
T Takamizawa ◽  
...  
Keyword(s):  
Sessile Drop ◽  
Contact Angles ◽  
Inhibition Layer ◽  
Universal Adhesive ◽  
Water Contact ◽  
Oxygen Inhibition ◽  
Fatigue Durability ◽  
Shear Fatigue ◽  
Universal Adhesives ◽  
Interfacial Characteristics

SUMMARY Objective: The purpose of this study was to evaluate the effect of the oxygen inhibition layer of universal adhesive on enamel bond fatigue durability and interfacial characteristics with different etching modes. Methods: The three universal adhesives used were Scotchbond Universal Adhesive (3M ESPE, St Paul, MN, USA), Adhese Universal (Ivoclar Vivadent, Schaan, Lichtenstein), and G-Premio Bond (GC, Tokyo, Japan). The initial shear bond strength and shear fatigue strength to enamel was determined in the presence and absence of the oxygen inhibition layer, with and without phosphoric acid pre-etching. The water contact angle was also measured in all groups using the sessile drop method. Results: The enamel bonding specimens with an oxygen inhibition layer showed significantly higher (p<0.05) initial shear bond strengths and shear fatigue strengths than those without, regardless of the adhesive type and etching mode. Moreover, the water contact angles on the specimens with an oxygen inhibition layer were significantly lower (p<0.05) than on those without, regardless of etching mode. Conclusion: The results of this study suggest that the oxygen inhibition layer of universal adhesives significantly increases the enamel bond fatigue durability and greatly changes interfacial characteristics, suggesting that the bond fatigue durability and interfacial characteristics of these adhesives strongly rely on its presence.

scholarly journals Impact of Air Exposure Time on the Water Contact Angles of Daily Disposable Silicone Hydrogels

2019 ◽  
Vol 20 (6) ◽  
pp. 1313 ◽  
Author(s):  
Petar Eftimov ◽  
Norihiko Yokoi ◽  
Nikola Peev ◽  
Georgi Georgiev
Keyword(s):  
Surface Coating ◽  
Sessile Drop ◽  
High Surface ◽  
Tear Film ◽  
Contact Angles ◽  
Water Contact ◽  
Air Exposure ◽  
Film Stability ◽  
Silicone Hydrogel ◽  
Silicone Hydrogels

The wettability of silicone hydrogel (SiHy) contact lens (CLs) is crucial for the pre-lens tear film stability throughout the day. Therefore, sessile drop and captive bubble setups were used to study the advancing and receding water contact angles (CA) of four SiHy materials: narafilcon A (TE), senofilcon A (AOD), stenfilcon A (MD), and delefilcon A (DT). TE and AOD have 48% and 38% water content, respectively, and no surface coating. MD (54% water) implements “smart chemistry” with just 4.4% bulk silicone content, while DT has >80% water at its surface. These SiHy were subjected to continuous blink-like air exposure (10 s)/rehydration (1s) cycles for 0, 1, 2, 3, 4, 6, 8, 10, 12, 14, and 16 h. The advancing CA, which measures the rehydration propensity of the CL surface, proved to be the most sensitive parameter to discriminate between the samples. The order of performance for the entire time scale was DT > MD >> AOD ≥ TE. The extended desiccation/rehydration cycling increased the differences between the CA of DT and MD compared to AOD and TE. This suggests that the low Si surface content and the high surface hydration are major determinants of SiHy wettability.

Co-Electrospinning of Microbial Polyester/Gelatin and their Interaction with Fibroblasts

2007 ◽  
Vol 342-343 ◽  
pp. 201-204 ◽  
Author(s):  
So Hee Yun ◽  
Ga Young Jun ◽  
Kwan Han Yoon ◽  
Yong Soon Park ◽  
Young Jin Kim ◽  
...  
Keyword(s):  
Tissue Engineering ◽  
Cell Attachment ◽  
Human Fibroblasts ◽  
Average Diameter ◽  
Tissue Engineering Scaffold ◽  
Promising Method ◽  
Initial Cell ◽  
Electrospinning Method ◽  
Biodegradable Poly ◽  
Mediate Cell

Biodegradable poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) nanofibrous matrix containing gelatin was fabricated by electrospinning method. The average diameter of electrospun PHBV/Gelatin (1:1) nanofibers was 600 nm determined by FE-SEM. ATR-FTIR and ESCA measurements were used to confirm the presence of gelatin in PHBV/Gelatin nanofibers. Human fibroblasts' behavior on PHBV/Gelatin nanofibrous matrix has been investigated. Fibroblasts were well attached on the surface of control PHBV and PHBV/Gelatin nanofibers. Initial cell attachment on PHBV/Gelatin nanofibers was higher than that of control PHBV nanofibers. Gelatin has many RGD moiety that mediate cell attachment. From this reason, initial cell attachment increased on the surface of PHBV/Gelatin nanofibers. From the results, coelectrospinning of PHBV and gelatin is a promising method for tissue engineering scaffold.

The Study on the Synthesis of Polyfluoroacrylate

2013 ◽  
Vol 395-396 ◽  
pp. 351-354
Author(s):  
Qin Huan Yang
Keyword(s):  
Contact Angle ◽  
Particle Size ◽  
Polymer Film ◽  
Water Contact Angle ◽  
Film Surface ◽  
Contact Angles ◽  
Fluoride Content ◽  
Water Contact ◽  
Copolymer Films ◽  
High Fluoride

Cationic polyfluoroacrylate has been synthesized in the dual presence of cationic and non-ionic emulsifiers. Optimization studies indicated that the optimal proportions of cationic emulsifier 1631 and non-ionic emulsifiers FSA and AEO-9 were 1.75%, 1.25%, and 0.08%, respectively. Under these conditions, the conversion to the polymer was 92.5%, the particle size was 142 nm, and the water contact angle on a polymer film surface was 94.0°. With increasing dosage of hydrocarbon emulsifier, the water contact angles of copolymer films decreased dramatically. The magnitude of this decrease for a polymer with low fluoride content was greater than that for a polymer with high fluoride content. The fluorinated emulsifier FSA behaved similarly to the hydrocarbon emulsifier.

scholarly journals A Mild Method for Surface-Grafting PEG Onto Segmented Poly(Ester-Urethane) Film with High Grafting Density for Biomedical Purpose

Polymers ◽  
2018 ◽  
Vol 10 (10) ◽  
pp. 1125 ◽  
Author(s):  
Lulu Liu ◽  
Yuanyuan Gao ◽  
Juan Zhao ◽  
Litong Yuan ◽  
Chenglin Li ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Molecular Weight ◽  
Photoelectron Spectroscopy ◽  
Platelet Adhesion ◽  
Film Surface ◽  
Contact Angles ◽  
Marginal Effect ◽  
Water Contact ◽  
Surface Hydrophilicity ◽  
Grafting Density

In the paper, poly(ethylene glycol) (PEG) was grafted on the surface of poly(ester-urethane) (SPEU) film with high grafting density for biomedical purposes. The PEG-surface-grafted SPEU (SPEU-PEG) was prepared by a three-step chemical treatment under mild-reaction conditions. Firstly, the SPEU film surface was treated with 1,6-hexanediisocyanate to introduce -NCO groups on the surface with high density (5.28 × 10−7 mol/cm2) by allophanate reaction; subsequently, the -NCO groups attached to SPEU surface were coupled with one of -NH2 groups of tris(2-aminoethyl)amine via condensation reaction to immobilize -NH2 on the surface; finally, PEG with different molecular weight was grafted on the SPEU surface through Michael addition between terminal C = C bond of monoallyloxy PEG and -NH2 group on the film surface. The chemical structure and modified surface were characterized by FT-IR, 1H NMR, X-ray photoelectron spectroscopy (XPS), and water contact angle. The SPEU-PEGs displaying much lower water contact angles (23.9–21.8°) than SPEU (80.5°) indicated that the hydrophilic PEG chains improved the surface hydrophilicity significantly. The SPEU-PEG films possessed outstanding mechanical properties with strain at break of 866–884% and ultimate stress of 35.5–36.4 MPa, which were slightly lower than those of parent film, verifying that the chemical treatments had minimum deterioration on the mechanical properties of the substrate. The bovine serum albumin adsorption and platelet adhesion tests revealed that SPEU-PEGs had improved resistance to protein adsorption (3.02–2.78 μg/cm2) and possessed good resistance to platelet adhesion (781–697 per mm2), indicating good surface hemocompatibility. In addition, due to the high grafting density, the molecular weight of surface-grafted PEG had marginal effect on the surface hydrophilicity and hemocompatibility.

scholarly journals Chitosan Films Incorporated with Exopolysaccharides from Deep Seawater Alteromonas sp.

Marine Drugs ◽  
2020 ◽  
Vol 18 (9) ◽  
pp. 447
Author(s):  
Iratxe Zarandona ◽  
Mónica Estupiñán ◽  
Carla Pérez ◽  
Laura Alonso-Sáez ◽  
Pedro Guerrero ◽  
...  
Keyword(s):  
Optical Properties ◽  
Mechanical Performance ◽  
Rough Surfaces ◽  
Film Surface ◽  
Contact Angles ◽  
Deep Seawater ◽  
Water Contact ◽  
Hydrophobic Character ◽  
Film Forming ◽  
Chitosan Films

Two Alteromonas sp. strains isolated from deep seawater were grown to promote the production of exopolysaccharides (EPS, E611 and E805), which were incorporated into chitosan solutions to develop films. The combination of the major marine polysaccharides (chitosan and the isolated bacterial EPS) resulted in the formation of homogenous, transparent, colorless films, suggesting good compatibility between the two components of the film-forming formulation. With regards to optical properties, the films showed low values of gloss, in the range of 5–10 GU, indicating the formation of non-glossy and rough surfaces. In addition to the film surface, both showed hydrophobic character, with water contact angles higher than 100 º, regardless of EPS addition. Among the two EPS under analysis, chitosan films with E805 showed better mechanical performance, leading to resistant, flexible, easy to handle films.

scholarly journals Fabrication and Characterization of Thermoresponsive Polystyrene Nanofibrous Mats for Cultured Cell Recovery

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Hwan Hee Oh ◽  
Young-Gwang Ko ◽  
Hiroshi Uyama ◽  
Won Ho Park ◽  
Donghwan Cho ◽  
...  
Keyword(s):  
Cell Growth ◽  
Graft Polymerization ◽  
Cultured Cells ◽  
Fiber Diameter ◽  
Human Fibroblasts ◽  
Biological Functions ◽  
Cell Recovery ◽  
Culture Surface ◽  
Fabrication And Characterization

Rapid cell growth and rapid recovery of intact cultured cells are an invaluable technique to maintain the biological functions and viability of cells. To achieve this goal, thermoresponsive polystyrene (PS) nanofibrous mat was fabricated by electrospinning of PS solution, followed by the graft polymerization of thermoresponsive poly(N-isopropylacrylamide)(PIPAAm) on PS nanofibrous mats. Image analysis of the PS nanofiber revealed a unimodal distribution pattern with 400 nm average fiber diameter. Graft polymerization of PIPAAm on PS nanofibrous mats was confirmed by spectroscopic methods such as ATR-FTIR, ESCA, and AFM. Human fibroblasts were cultured on four different surfaces, PIPAAm-grafted and ungrafted PS dishes and PIPAAm-grafted and ungrafted PS nanofibrous mats, respectively. Cells on PIPAAm-grafted PS nanofibrous mats were well attached, spread, and proliferated significantly much more than those on other surfaces. Cultured cells were easily detached from the PIPAAm-grafted surfaces by decreasing culture temperature to 20°C, while negligible cells were detached from ungrafted surfaces. Moreover, cells on PIPAAm-grafted PS nanofibrous mats were detached more rapidly than those on PIPAAm-grafted PS dishes. These results suggest that thermoresponsive nanofibrous mats are attractive cell culture substrates which enable rapid cell growth and recovery from the culture surface for application to tissue engineering and regenerative medicine.

Sign in / Sign up

Export Citation Format

Share Document