Structural, chemical and biological properties of carbon layers sputtered on polyethyleneterephtalate

Abstract

Carbon layers on polyethyleneterephtalate (PET) backing were prepared by sputtering from graphite target. UV-VIS, Raman spectroscopy, RBS (Rutherford backscattering) and ERDA (Elastic Recoil Detection Analysis) techniques were used for the characterization of the layers. Surface morphology of the layers was determined by AFM technique and the adhesion of 3T3 mouse fibroblasts on the layers was studied in vitro. It was found that the properties of the deposited carbon layer depend on the sputtering time. The concentration of conjugated double bonds, fraction of amorphous hydrogenated carbon (a-C:H) containing oxygen and surface roughness are increasing functions of the sputtering time. The changes of the layer surface morphology with increasing sputtering time were also observed. For the sputtering times up to 30' the number of adhering 3T3 cells increases with increasing sputtering time. For longer sputtering times, however, the cell adhesion becomes lower probably due to unfavorable changes in roughness and morphology of the layer.

Characterization and cytocompatibility of carbon layers prepared by photo-induced chemical vapor deposition

“…Surface wettability, can be characterized by water contact angle, mainly influence adhesion of cells on the modified polymer [24]. The dependence of the water contact angle on the carbon deposition time on the PTFE is shown in Fig.…”

The Properties and Application of Carbon Nanostructures

“…It was found that after 15 s of deposition carbon creates rounded, regular grains the size of which is larger compared to those observed for longer sputtering times [45]. For the sputtering times above 30 s the carbon grains become smaller but some irregularities arise.…”

“…Thin carbon layers are considered as a prospective material for a wide range of biomedical application [39,[43][44][45], e.g. tissue regeneration [46], controlled drug delivery [47], surface coating for bone-related implants [48], increase of resistance to microbial adherence, blood interfacing implants applications [49] or neuronal growth.…”

“…Surface wettability can be characterized by water contact angle, mainly influencing adhesion of cells on the modified polymer [45]. Pristine PTFE is a strongly hydrophobic material with a very high contact angle.…”

“…The oxygen containing groups are probably either formed due to reactions layer with residual gases in reaction chamber or due to oxidation of unsaturated radicals by the exposure of samples to air after the deposition. The occurrence of polar oxygen containing groups and remaining radicals are suggested to be the main reason for the low water contact angle [45].…”