Surface Modification of Chitosan Membranes by Oxygen Plasma Treatment

2009 ◽  
Vol 610-613 ◽  
pp. 1259-1262 ◽  
Author(s):  
Na Ru Zhao ◽  
Ying Jun Wang ◽  
Li Ren ◽  
Xiao Feng Chen

Chitosan membranes were prepared by solvent cast method. In order to increase cell adhesion of the chitosan membranes, oxygen plasma treatment was applied to improve the hydrophilicity of the surface of chitosan membranes. The surface properties were characterized by scanning electron microscopy (SEM), contact angle analyzer, X-ray photoelectron spectroscopy (XPS). The effects of exposure time, plasma generating power, and chamber pressure on water contact angle of the chitosan membranes were investigated. The water contact angle of chitosan membranes decreased from 94.1° to 49.2° after plasma treatment. Which suggested the surfaces became more hydrophilic. XPS analysis showed that the oxygen content and the ratio of O/C increased markedly after oxygen plasma treatment. Furthermore, it was found that C-H bonds were broken with oxygen plasma treatment. C-OH group had been increased after plasma irradiation.

2021 ◽  
Vol 22 (13) ◽  
pp. 6672
Author(s):  
Nina Recek ◽  
Matej Holc ◽  
Alenka Vesel ◽  
Rok Zaplotnik ◽  
Peter Gselman ◽  
...  

Seeds of common bean (Phaseolus vulgaris L.), of the Etna variety, were treated with low-pressure oxygen plasma sustained by an inductively coupled radiofrequency discharge in the H-mode for a few seconds. The high-intensity treatment improved seed health in regard to fungal contamination. Additionally, it increased the wettability of the bean seeds by altering surface chemistry, as established by X-ray photoelectron spectroscopy, and increasing surface roughness, as seen with a scanning electron microscope. The water contact angle at the seed surface dropped to immeasurably low values after a second of plasma treatment. Hydrophobic recovery within a month returned those values to no more than half of the original water contact angle, even for beans treated for the shortest time (0.5 s). Increased wettability resulted in accelerated water uptake. The treatment increased the bean radicle length, which is useful for seedling establishment in the field. These findings confirm that even a brief plasma treatment is a useful technique for the disinfection and stimulation of radicle growth. The technique is scalable to large systems due to the short treatment times.


Coatings ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1326
Author(s):  
Ting-Yi Chiang ◽  
Chun-Chuan Yang ◽  
Yi-Hsuan Chen ◽  
Min Yan ◽  
Shinn-Jyh Ding

Improving the bond strength of veneering ceramics to ZrO2-based cores remains a challenge. The purpose of this study was to evaluate the shear bond strength of different ZrO2 cores containing calcium silicate (CaSi) to veneering ceramics. Five types of ZrO2-based cores (n = 230) were divided into two groups: with or without oxygen plasma treatment. These were bound to two veneering ceramics (IPS e.max Ceram or VITA VM9). Shear bond strength of veneering ceramics to various cores was measured (n = 10), in addition to phase composition, surface morphology and contact angle of the cores. The results indicated that the plasma treatment had a significant effect on the water contact angle of the ZrO2-based cores, but had little effect on the bond strength. Regardless of plasma treatment, the highest strength value was recorded in the ZrO2 core specimen containing 20 wt % CaSi, when all cores were adhered to VITA VM 9 veneer. When using IPS e.max Ceram veneer, the shear bond strength of the plasma-treated 20 wt % CaSi-containing ZrO2 core was 16.6 ± 0.9 MPa higher than that of VITA In-Ceram YZ core control (13.4 ± 1.0 MPa) (p < 0.05). We conclude that the presence of 20 wt % CaSi in ZrO2 can improve the shear bond strength of zirconia-based cores to veneering ceramic.


2017 ◽  
Vol 7 ◽  
pp. 184798041770279 ◽  
Author(s):  
Baojiang Liu ◽  
Taizhou Tian ◽  
Jinlong Yao ◽  
Changgen Huang ◽  
Wenjun Tang ◽  
...  

A robust superhydrophobic organosilica sol-gel-based coating on a cotton fabric substrate was successfully fabricated via a cost-effective one-step method. The coating was prepared by modification of silica nanoparticles with siloxane having long alkyl chain that allow to reduce surface energy. The coating on cotton fabric exhibited water contact angle of 151.6°. The surface morphology was evaluated by scanning electron microscopy, and surface chemical composition was measured with X-ray photoelectron spectroscopy. Results showed the enhanced superhydrophobicity that was attributed to the synergistic effect of roughness created by the random distribution of silica nanoparticles and the low surface energy imparted of long-chain alkane siloxane. In addition, the coating also showed excellent durability against washing treatments. Even after washed for 30 times, the specimen still had a water contact angle of 130°, indicating an obvious water-repellent property. With this outstanding property, the robust superhydrophobic coating exhibited a prospective application in textiles and plastics.


2019 ◽  
Vol 9 (12) ◽  
pp. 1653-1661
Author(s):  
Tiandong Cao ◽  
Fangrui Dong ◽  
Pengfei Zhang ◽  
Jingying Liu ◽  
Zhe Xing ◽  
...  

3D poly(glycerol-sebacate)/poly(L-lactic-acid) (PGS/PLLA) scaffolds, produced by thermally induced phase separation (TIPS) method were treated with oxygen plasma in order to reduce the hydrophobicity of the PGS/PLLA membranes. After the oxygen plasma treatment, the pore size of scaffolds became uniform as well as an increasing in the roughness of the surface. No influence on chemical characteristics such as composition and bond types of PLLA was detected after the treatment. However, the change in the ratio of the scaffold elements before and after the oxygen plasma treatment was detected. Oxygen plasma treatment reduced the average of water contact angle of the TIPS film from 103.7± 10.1 to 64.7± 12.6 at the maximum exposure time (970 s) and power (100 W). The results showed that the goat temporomandibular joint (TMJ) cells attached well to the surface of the oxygen plasma modified scaffold. Furthermore, this modification significantly enhanced cell viability, increased cell proliferation and expression of related genes (Collagen type I mRNA and Collagen type II mRNA). The results demonstrated that it is a promising modification method to promote applications of PGS/PLLA based scaffolds to the regeneration of TMJ discs.


2012 ◽  
Vol 1395 ◽  
Author(s):  
Jason H. C. Yang ◽  
Kungen Teii

ABSTRACTNanocrystalline diamond (NCD) films are prepared from Ar-rich/N2/CH4 and Ar-rich/H2/CH4 mixtures by microwave plasma-enhanced chemical vapor deposition, and further treated by microwave hydrogen and oxygen plasma exposures separately to enhance the wetting property. The hydrogen plasma treatment has small effect on the surface roughness, while the oxygen plasma treatment forms fine protrusions on the film surface. Results show that the wettability of the hydrogen plasma treated NCD film is nearly constant or little improvement as the polar component of the apparent surface free energy is close to the as-deposit NCD film. In contrast, the wettability of the oxygen plasma treated NCD film is improved dramatically such that the contact angle is reduced from 92º and 4.7º to almost 0º for water and 1-bromonaphthalene, respectively, and the polar component increases significantly to 34 mJ/m2. The low contact angle suggests that the film is considerably a cell adhesive friendly surface, which is essential in maintaining multicellular structure, and thus making it a favorable wetting surface for biological and biomedical applications.


2006 ◽  
Vol 15-17 ◽  
pp. 187-192 ◽  
Author(s):  
Ko Shao Chen ◽  
Su Chen Chen ◽  
Yi Chun Yeh ◽  
Wei Cheng Lien ◽  
Hong Ru Lin ◽  
...  

Expanded polytetrafluoroethylene (ePTFE) is a bioinert material. To improve the ePTFE film biocompatibility, the cold plasma technology was used with acetic acid as monomer to deposit onto ePTFE film and then (N-isopropylacrylamide) was grafted onto the surface by photo-grafting. The characteristics of the surface were evaluated with X-ray photoelectron spectroscopy (XPS), FTIR and water contact angle. It was found that the contact angle of water on the untreated ePTFE significantly decrease from125° to 72° after ePTFE film being treated with acetic acid plasma deposition treatment. Due to the hydrophilicity of poly(N-isopropylacrylamide), the contact angle of water on the ePTFE-g-NIPAAm approached to 0°.


2011 ◽  
Vol 306-307 ◽  
pp. 1631-1634 ◽  
Author(s):  
Ya Kai Feng ◽  
Da Zhi Yang ◽  
Hai Yang Zhao ◽  
Jin Tang Guo ◽  
Qing Liang Chen ◽  
...  

Poly(3-dimethyl(methacryloyloxyethyl)ammonium propane sulfonate) (poly(DMAPS)) zwitterionic brushes were grafted onto the polycarbonateurethane (PCU) surface to improve its hydrophilicity and hemocompatibility by Ultraviolet (UV) polymerization. Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS) and water contact angle were used to characterize the chemical and physical properties of the modified PCU surface. DMAPS-grafted PCU films showed significantly high hydrophilicity owing to the high hydrophilic poly(DMAPS) zwitterionic brushes. The cytotoxicity tests revealed the sulfoammonium zwitterionic brushes modified PCU film had good cytocompatibility. In addition, the hemocompatibility of the modified PCU films was evaluated by hemolytic tests and platelet adhesion tests. The PCU films modified with zwitterionic brushes had a lower hemolytic index, showed effective resistance to platelet adhesion. Due to the fact that sulfoammonium zwitterionic brushes can improve the hemocompatibility of the PCU surface, this gives rise to its potential application as blood-contacting materials or devices.


2013 ◽  
Vol 747 ◽  
pp. 182-185
Author(s):  
Tharinee Theerathanagorn ◽  
Boonlom Thavornyutikarn ◽  
Wanida Janvikul

In this study, poly (glycerol sebacate) (PGS) was initially synthesized via condensation polymerization of glycerol and sebacic acid at equimolar ratio (1:1) at 130°C for 24 h. The number average molecular weight (Mn) of the resulting polymer determined by gel permeation chromatography (GPC) was about 2800 g/mol. Porous PGS scaffolds were subsequently prepared by a particle-leaching technique. NaCl was added into the polymer at 60-90% w/w; the mixtures were cured in Teflon molds at 140°C for 16 h. The porous scaffolds were further subjected to surface treatment with low pressure oxygen plasma to increase surface carboxyl and hydroxyl groups and thereby enhance hydrophilicity of PGS scaffold surface. The surface morphology and wettability of both untreated PGS and plasma-treated PGS scaffolds were comparatively determined by scanning electron microscopy (SEM) and water contact angle measurement, respectively. A considerable decrease in water contact angle was observed on the PGS scaffolds after the plasma treatment. The surface chemistry, mechanical strength and degree of swelling of the PGS scaffolds were also assessed by X-ray photoelectron spectroscopy (XPS), dynamic mechanical analysis (DMA) and swelling measurement, respectively.


2011 ◽  
Vol 306-307 ◽  
pp. 3-6
Author(s):  
Hai Yang Zhao ◽  
Ya Kai Feng ◽  
Da Zhi Yang ◽  
Jin Tang Guo ◽  
Qing Liang Chen ◽  
...  

In order to improve the hemocompatibility of polycarbonateurethane (PCU), the biomimetic phosphorylcholine (PC) group was introduced onto material surface. Brush structure having PC groups was formed by ultraviolet (UV) initiated polymerization of 2-methacryloyloxyethyl phosphorylcholine (MPC) to improve the hydrophilicity and hemocompatibility of PCU surfaces. Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electrical microscopy (SEM) and water contact angle were used to characterize the chemical and physical properties of the modified PCU surfaces. Compared with original PCU, the PC-grafted PCU surfaces showed significantly high hydrophilicity as indicating by low water contact angle. The hemocompatibility of the PC-grafted PCU surfaces was evaluated by platelet adhesion test. The PCU surfaces modified with phosphorylcholine zwitterionic brushes showed effective resistance to platelet adhesion and high hemocompatibility. These PC-grafted PCU materials will have potential application as blood-contacting materials or devices due to their good mechanical and hemocompatible properties.


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