Immobilization of Silk Fibroin as Scaffold for Cell Culture by Plasma Grafting Polymerization

According to the low efficiency of cell attachment and proliferation on commercial polystyrene (PS) dish, scaffold with porous structure on the polystyrene dish is required to improve the cell attachment and proliferation efficiency on the dish. The scaffold with porous structure was fabricated from a solution of powdered silk fibroin by plasma grafting polymerization technique. Argon plasma was utilized by a 13.56 MHz capacitively coupled discharge (CCP) reactor at working pressure of 100 mTorr. Rf power, plasma treatment time, and the cycle of grafting on the dish were varied. The proper treatment time and rf power set to 10 minutes and 100 W, respectively. The experimental results showed the uniformly and highly distributed of porosity of fibroin scaffold on the PS dish surface. The Ar-treated dish had lower UV-Vis absorbance than the untreated dish indicating the efficiency of grafting between fibroin structure and treated PS surface is better than the untreated surface. The absorbance spectra of phanyalanine at 280 nm affirmed the success of the fibroin amino acid grafting to PS aromatic structure.

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Controlled radical polymerization of hydrophilic and zwitterionic brush-like polymers from silk fibroin surfaces

Journal of Materials Chemistry B ◽

10.1039/d0tb01990a ◽

2020 ◽

Vol 8 (45) ◽

pp. 10392-10406

Author(s):

Danielle L. Heichel ◽

Ngoc Chau H. Vy ◽

Shawn P. Ward ◽

Douglas H. Adamson ◽

Kelly A. Burke

Keyword(s):

Protein Adsorption ◽

Radical Polymerization ◽

Silk Fibroin ◽

Cell Attachment ◽

Controlled Radical Polymerization

Silk fibroin films were modified with zwitterionic and hydrophilic brush-like polymers via surface-initiated ATRP, resulting in surfaces that reduced protein adsorption and cell attachment.

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Effect of Low-Pressure Plasma Treatment Parameters on Wrinkle Features

Materials ◽

10.3390/ma13173852 ◽

2020 ◽

Vol 13 (17) ◽

pp. 3852

Author(s):

Bongjun Gu ◽

Dongwook Ko ◽

Sungjin Jo ◽

Dong Choon Hyun ◽

Hyeon-Ju Oh ◽

...

Keyword(s):

Power Flow ◽

Treatment Time ◽

Argon Plasma ◽

Negative Ions ◽

Low Pressure ◽

Nitrogen Plasma ◽

Pressure Plasma ◽

Positive Ions ◽

Low Pressure Plasma ◽

Optical Adhesive

Wrinkles attract significant attention due to their ability to enhance the mechanical and optical characteristics of various optoelectronic devices. We report the effect of the plasma gas type, power, flow rate, and treatment time on the wrinkle features. When an optical adhesive was treated using a low-pressure plasma of oxygen, argon, and nitrogen, the oxygen and argon plasma generated wrinkles with the lowest and highest wavelengths, respectively. The increase in the power of the nitrogen and oxygen plasma increased the wavelengths and heights of the wrinkles; however, the increase in the power of the argon plasma increased the wavelengths and decreased the heights of the wrinkles. Argon molecules are heavier and smaller than nitrogen and oxygen molecules that have similar weights and sizes; moreover, the argon plasma comprises positive ions while the oxygen and nitrogen plasma comprise negative ions. This resulted in differences in the wrinkle features. It was concluded that a combination of different plasma gases could achieve exclusive control over either the wavelength or the height and allow a thorough analysis of the correlation between the wrinkle features and the characteristics of the electronic devices.

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Surface Properties of UHMWPE Fiber after Low Temperature Argon-Plasma Treatment

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.499.90 ◽

2012 ◽

Vol 499 ◽

pp. 90-94 ◽

Cited By ~ 2

Author(s):

Jin Yun Xu ◽

Wen Yu Wang ◽

Xin Jin

Keyword(s):

Molecular Weight ◽

Low Temperature ◽

Plasma Treatment ◽

Treatment Time ◽

Argon Plasma ◽

Uhmwpe Fiber ◽

Wetting Ability ◽

Plasma Treatment Time ◽

Uhmwpe Fibers ◽

Ultra High Molecular Weight

To improve the adhesion between ultra-high-molecular-weight polyethylene (UHMWPE) fibers and matrix, the UHMWPE fibers were treated by low temperature argon-plasma. The effects of argon-plasma treatment on the properties of UHMWPE have been investigated. The roughness and wetting ability were all found to increase significantly after modifications. The tensile strength of UHMWE fibers were decreased with the plasma treatment time. The optimum plasma treatment is 2min.The increasing of roughness and wetting ability of UHMWPE fiber are beneficial to the improvement the adhesion between UHMWPE fiber and matrix.

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Enhanced Chondrogenic Responses of Human Articular Chondrocytes Onto Silk Fibroin/Wool Keratose Scaffolds Treated With Microwave-Induced Argon Plasma

Artificial Organs ◽

10.1111/j.1525-1594.2009.00871.x ◽

2010 ◽

Vol 34 (5) ◽

pp. 384-392 ◽

Cited By ~ 21

Author(s):

Young Woo Cheon ◽

Won Jai Lee ◽

Hyun Sook Baek ◽

Young Dae Lee ◽

Jong-Chul Park ◽

...

Keyword(s):

Silk Fibroin ◽

Articular Chondrocytes ◽

Argon Plasma ◽

Human Articular Chondrocytes

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Change of the critical thickness in the preferred orientation of TiN films

Journal of Materials Research ◽

10.1557/jmr.1995.0634 ◽

1995 ◽

Vol 10 (3) ◽

pp. 634-639 ◽

Cited By ~ 35

Author(s):

U.C. Oh ◽

Jung Ho Je ◽

Jeong Y. Lee

Keyword(s):

Strain Energy ◽

Unit Volume ◽

Critical Thickness ◽

Preferred Orientation ◽

Rf Power ◽

X Ray Diffraction ◽

Working Pressure ◽

Cross Sectional ◽

Tin Films ◽

Tin Thin Films

Recently it was observed through cross-sectional TEM that the preferred orientation of the TiN thin film was changed from (200) to (111) with thickness. In this study, the process of the change in the preferred orientation was studied near the critical thickness by x-ray diffraction, and the value of the critical thickness could be estimated. The change of the critical thickness was also investigated with the strain energy per unit volume. The strain energy could be changed by controlling the energy of the bombarding particle, i.e., by adjusting the rf power, the working pressure, and the substrate bias in sputtering. The critical thickness was decreased monotonically in all cases as the energy of the bombarding particle or the strain energy per unit volume was increased. These results surely show the dependence of the change of the preferred orientation on the strain energy in the TiN thin films.

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Multi-Component ZnO-In2O3-SnO2Thin Films Deposited by RF Magnetron Co-Sputtering

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.124-126.119 ◽

2007 ◽

Vol 124-126 ◽

pp. 119-122 ◽

Cited By ~ 1

Author(s):

Chang Sik Son ◽

Jae Sung Hur ◽

Byoung Hoon Lee ◽

Sang Yul Back ◽

Jeong Seop Lee ◽

...

Keyword(s):

Thin Films ◽

Room Temperature ◽

Visible Range ◽

Rf Power ◽

Working Pressure ◽

Average Transmittance ◽

Sno2 Thin Films ◽

Ar Gas ◽

Sputtering System ◽

High Chemical Stability

Multi-component ZnO-In2O3-SnO2 thin films have been prepared by RF magnetron co-sputtering using targets composed of In4Sn3O12(99.99%) [1] and ZnO(99.99%) at room temperature. In4Sn3O12 contains less In than commercial ITO, so that it lowers cost. Working pressure was held at 3 mtorr flowing Ar gas 20 sccm and sputtering time was 30 min. RF power ratio [RF1 / ( RF1 + RF2 )] of two guns in sputtering system was varied from 0 to 1. Each RF power was varied 0~100W respectively. The thicknesses of the films were 350~650nm. The composition concentrations of the each film were measured with EPMA and AES. The low resistivity of 1-2 × 10-3 and an average transmittance above 80% in the visible range were attained for the films over a range of δ (0.3 ≤ δ ≤ 0.5). The films also showed a high chemical stability with time and a good uniformity.

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Management of wide open apices in non-vital permanent teeth with Ca(OH)2 paste

Journal of Clinical Pediatric Dentistry ◽

10.17796/jcpd.25.1.n224g827014n02n2 ◽

2001 ◽

Vol 25 (1) ◽

pp. 51-56 ◽

Cited By ~ 16

Author(s):

Tarun Walia ◽

Harpinder Singh Chawla ◽

Krishan Gauba

Keyword(s):

Retrospective Study ◽

Root Growth ◽

Porous Structure ◽

Success Rate ◽

Treatment Time ◽

Permanent Teeth ◽

Older Children ◽

Barrier Formation ◽

Open Apices ◽

One Year

A retrospective study on 15 non-vital immature incisor teeth was done using Ca(OH)2 Pulpdent® paste. A success rate of 100 percent was achieved within one year. The variables influencing the time taken for apexification were also evaluated. The teeth were followed up to a period of 24 months. It was found that older children having narrow open apex had a shorter treatment time than the younger children (NS); teeth without periapical infection showed some amount of root growth and closing of apex that was faster than those with periapical infection (p<0.001). The calcified bridge formed following apexification is a porous structure. This investigation provides information about the time taken and procedure required to achieve apical barrier formation in non-vital immature incisors.

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Plasma Treatment Limits Human Melanoma Spheroid Growth and Metastasis Independent of the Ambient Gas Composition

Cancers ◽

10.3390/cancers12092570 ◽

2020 ◽

Vol 12 (9) ◽

pp. 2570 ◽

Cited By ~ 4

Author(s):

Sybille Hasse ◽

Tita Meder ◽

Eric Freund ◽

Thomas von Woedtke ◽

Sander Bekeschus

Keyword(s):

Plasma Treatment ◽

Treatment Time ◽

Argon Plasma ◽

Ambient Air ◽

Human Melanoma ◽

Melanoma Metastasis ◽

Spheroid Growth ◽

Tumor Entity ◽

Melanoma Treatment ◽

Jet Plasma

Melanoma skin cancer is still a deadly disease despite recent advances in therapy. Previous studies have suggested medical plasma technology as a promising modality for melanoma treatment. However, the efficacy of plasmas operated under different ambient air conditions and the comparison of direct and indirect plasma treatments are mostly unexplored for this tumor entity. Moreover, exactly how plasma treatment affects melanoma metastasis has still not been explained. Using 3D tumor spheroid models and high-content imaging technology, we addressed these questions by utilizing one metastatic and one non-metastatic human melanoma cell line targeted with an argon plasma jet. Plasma treatment was toxic in both cell lines. Modulating the oxygen and nitrogen ambient air composition (100/0, 75/25, 50/50, 25/75, and 0/100) gave similar toxicity and reduced the spheroid growth for all conditions. This was the case for both direct and indirect treatments, with the former showing a treatment time-dependent response while the latter resulted in cytotoxicity with the longest treatment time investigated. Live-cell imaging of in-gel cultured spheroids indicated that plasma treatment did not enhance metastasis, and flow cytometry showed a significant modulation of S100A4 but not in any of the five other metastasis-related markers (β-catenin, E-cadherin, LEF1, SLUG, and ZEB1) investigated.

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