Ammonia plasma treatment as a method promoting simultaneous hydrophilicity and antimicrobial activity of viscose wound dressings

Abstract

Viscose non-woven was treated by NH3 plasma. Different exposure times were used in order to find the optimum conditions for simultaneously improved hydrophilicity and antimicrobial activity, as desired effects by wound dressings. Both chemical and morphological modifications were studied by X-ray photoelectron spectroscopy and atomic force microscopy, respectively, revealing functionalization with nitrogen groups as well as formation of rich morphology at sub-micrometer scale. The wetting rise curves increased from 0.04 g2 s–1 for non-treated material to 1 g2 s−1 after prolonged treatment. The water contact angle decreased almost linearly with treatment time from 90° for non-treated samples to about 40° for samples treated for 140 s and remained rather constant thereafter. The AATCC 100–1999 standard test revealed reduction on all used bacteria, more pronounced for Gram-negative, that is, E. coli and P. aeruginosa, then for Gram-positive, that is, a significant for S. aureus and a marginal for E. faecalis.

On the Hydrophilicity and Water Resistance Effect of Styrene‐Acrylonitrile Copolymer Treated by CF4 and O2 Plasmas

“…CF 4 decomposes in a wide range of products, including neutrals, ions, and excited species; such as CF, CF 2 , CF 3 + or F • that most likely react with aromatic rings of the SAN backbone by electrophilic aromatic substitution, which is the reaction where a hydrogen atom of an aromatic ring is substituted as a result of an electrophilic attack on the ring. The benzene acts as a nucleophile, attacking the electrophile with a pair of its π‐electrons . In the case of the acrylonitrile part of the molecule, the fluorination may occur by an opposed way via nucleophilic substitution .…”

Fabrication of Superhydrophilic Polyester Fabrics Using Various TiO2Colloidal Dispersions

“…A total of 10 measurements were taken for each sample in order to calculate a statistical average. Capillary rise measurement procedure has been fully described in [6]. Shortly, the hydrophilic features were determined by measuring the weight increase (m) during liquid (Mili-Q water) penetration on account of capillary eect as a function of time (t).…”

Plasma Modified Textiles for Biomedical Applications

“…In two different papers Persin et al compared a few different treatment methods on viscose fibers to address both of these aspects [39,40]. In a first reaction pathway, a two-step process consisting of an oxygen plasma treatment, followed by the immobilization of AgCl particles, is followed.…”