Surface modification of PVC endotracheal tubes by oxygen glow discharge to reduce bacterial adhesion

Abstract

A d.c. oxygen glow discharge was used to modify medical-grade poly(vinyl chloride) (PVC) to study how surface chemistry and hydrophilicity influence Pseudomonas aeruginosa adhesion. The effects of plasma exposure time on the resulting surface, including chemical composition, wettability and roughness, were assessed using x-ray photoelectron spectroscopy, contact angle measurements and atomic force microscopy analysis. A significant alteration in the hydrophilicity of the native PVC surface was observed after oxygen glow discharge treatment. The water contact angle decreased from ∼80• to 8-20• , with a weak dependence of the exposure time used. The change in surface wettability resulted from the incorporation of oxygenated functional groups, including esters, ketones and acids, as indicated by XPS analysis. The amount of oxygen incorporation was shown to be essentially independent of plasma exposure time. However, prolonged plasma exposure resulted in increased surface roughness. Bacterial adhesion efficiency was evaluated for PVC modified by 120 s of plasma exposure, because this exposure time was determined to yield the maximum decrease in contact angle. Oxygen plasma treatment of native PVC was found to yield a 70% reduction in bacterial adhesion for the four strains of Pseudomonas aeruginosa tested.

Lipase degradation of plasticized polyvinyl chloride endotracheal tube surfaces to create nanoscale features

“…24,29 The change is further supported by the increased hydrophilicity of the nano-R materials, as seen in previous studies. 30,31 However, the O/C ratio for these materials did not change significantly with the 0.1% lipase treatment suggesting that bacterial adhesion and growth on the surface of the nano-R material is influenced by other factors than surface chemistry.…”

Adherence ability of Staphylococcus epidermidis on prosthetic biomaterials: an in vitro study

“…21,23,26 Boks et al reported that bond strengthening for four strains of S. epidermidis on a hydrophobic surface was fast and limited to a minor increase, while strengthening of the bonds on a hydrophilic surface increases significantly with contact time. 33 As water molecules adjacent to a hydrophobic surface are not able to form hydrogen bonds with that surface (hydrophobic effect), bacterial adhesion to a hydrophobic specimen is brought about by an entropically favorable release of water molecules.…”

“…19 Recently, there have been a number of reports on the impact on bacterial adhesion of surface roughness, wettability, and other physical properties of the actual solid materials themselves. [20][21][22][23][24][25][26][27][28] However, most of this research has been on dental implants, on the basis of conditions found in the mouth. [25][26][27][28] There is little research into the adhesion of S. epidermidis to other medical materials used in clinical practice, and their results were mostly inconsistent.…”

An in vitro bacterial adhesion assessment of surface-modified medical-grade PVC

“…Based on the data, the C12p atomic content is significantly lower than expected for a standard PVC containing no additives originating from the presence of several additives and also X-ray degradation [48]. Due to the same reason, a considerable amount of Ols is detected on the sample 1 surface which is not a typical element found in standard PVC.…”