Characterization of air plasma‐treated polymer surfaces by ESCA and contact angle measurements for optimization of surface stability and cell growth

Abstract

A radiofrequency air plasma has been used to incorporate new functionalities at the surface of cycloolefin polymers (Zeonex and Topas), polymethyl methacrylate (PMMA), styrene-acrylonitrile copolymer (SAN), and polystyrene (PS). The main goals with the plasma treatment of the different plastics were to hydrophilize the surfaces and to provide good cell culture properties. Surfaces treated at high RF power/gas flow ratios (50 to 100 W/sccm) became highly hydrophilic (water contact angles of about 5 degrees) and stable towards washing in 70% (v/v) ethanol. Those treated at lower power/gas flow ratios (3 to 10 W/sccm) were less hydrophilic and not wash-stable. Cell growth properties of HeLa cervix carcinoma cells as good as on commercial tissue-culture polystyrene could be obtained for Zeonex, SAN, and PS, treated at relatively low RF power/ gas flow ratios. However, no untreated plastics were suitable for culturing these cells. XPS spectra features show that ester, ether/alcohol, and ester/carboxyl groups are formed during the plasma treatments of the different plastics. Measurable amounts of carboxylic acid carbon after plasma treatment were only observed for PS and Topas. Furthermore, at high RF power/gas flow ratios fluorine, aluminium and silicon were incorporated in all investigated plastics surfaces due to ablation-deposition processes in the reaction chamber.

Surface modification of cycloolefinic copolymers for optimization of the adhesion to metals

“…3). Although the results found from Johansson et al 2 indicate that not only does the bulk polymer structure and the plasma condition influence the better adhesion, but also no additives affect the final result.…”

“…It is believed however that the majority of oxidation in the plasma is caused by radical reactions between the polymer chain backbones and atomic oxygen leading to formation of various functionalities such as hydro-peroxides, carbonyls, carboxylic acids, per acids, etc. 2 The COC materials do not inherently contain any oxygen or nitrogen atoms. From the curve fitting of the C 1s peaks (Fig.…”

“…There are alternative techniques to produce wash-stable hydrophilic surfaces of polymers such as plasma polymerization or grafting of hydrophilic polymeric species. 2 The aim of the present study was to optimize the adhesion between COC as the substrate material to different types of metals (Al and Cu). Selected types of COC were at first subjected to plasma treatment with variation of the treatment time and type of plasma gas.…”

Microwave plasma surface modification of silicone elastomer with allylamine for improvement of biocompatibility

“…1,2 A number of physical and chemical techniques can be used to improve the surface biocompatibility, [3][4][5][6][7][8] among them, plasma surface modification was proved to be a good method. 7,8 The plasma surface modification is one kind of economical and effective surface treatment technology to improve material's wettability, permeability, conductivity, adhesivity, biocompatibility, and so on.…”

“…7,8 The plasma surface modification is one kind of economical and effective surface treatment technology to improve material's wettability, permeability, conductivity, adhesivity, biocompatibility, and so on. 9 The unique advantage of plasma surface modification of biomaterials is that the surface properties and biocompatibility can be improved selectively while the bulk characteristics of the materials remain unchanged.…”