Surface Engineering by Coating of Hydrophilic Layers: Bioadhesion and Biocontamination

Abstract

Plasma techniques -plasma modification, plasma deposition and plasma and grafting reactions -are illustrated for the elaboration of tools, medical devices and biomaterials. These promising techniques are developed either for the sterilization, antifouling surfaces or for enhancing the biofilms formation.

Study of Surface Properties of Polyolefins Modified by Corona Discharge Plasma

“…The process of hydrophobic recovery20,45,64 of the corona discharge plasma treated iPP surface results from the tendency of the polymer to reduce its surface energy. The thermodynamic preferences influence the time dependent polar functional groups rearrangement in the direction of the polymer bulk, as well as the diffusion of low‐molecular additives, or oligomers towards the surface of the iPP34,53,54,58,65–73 Because of this, the degree of surface modification of iPP modified by the corona discharge is to certain extent dependent on the crystallinity of the polymer, and on the time elapsed after polymer modification 74,75. The mobility of macromolecules mainly occurs in the amorphous regions, and the mobility in the crystalline region is limited because of an orderly packed structure 69,76,77.…”

“…The hydrophobic recovery and the decrease of the surface energy and its polar component of corona discharge modified LDPE22,34,58,83–85 is caused by the following: the inter‐reactions of chemical groups on the corona‐treated surface of LDPE which have many functionalities available for specific interactions, the further oxidation and degradation upon exposure to air, when the unstable hydro‐peroxides and peroxides decompose forming the more stable ketonic and aldehydic groups, the migration of the low‐molecular mass oxidized material, e.g. the polar fragments, into the polymeric film to reach a thermodynamically more stable state with a lower value of the surface free energy, the low‐molecular mass compounds (processing additives, e.g.…”

Bioadhesion: a review of concepts and applications

“…This approach has been used to prevent the undesirable protein adhesion and the unwanted generation of inflammatory cells on poly(methyl methacrylate) (PMMA) contact lenses [52]. Specific functional groups can be covalently attached to substrate surfaces using chemical synthesis techniques to attach biomolecules and construct model systems for use in adhesion studies.…”

“…On the other hand, the use of fluorinated gases such as CF 4 in the plasma results in the introduction of a low surface energy polytetrafluoroethylenelike structure, enhancing surface hydrophobicity. This approach has been used to prevent the undesirable protein adhesion and the unwanted generation of inflammatory cells on poly(methyl methacrylate) (PMMA) contact lenses [52]. Specific functional groups can be covalently attached to substrate surfaces using chemical synthesis techniques to attach biomolecules and construct model systems for use in adhesion studies.…”

Polyvinyl Pyrrolidone-Chitosan Blend Membrane for Pervaporation Separation of Trimethyl Borate-Methanol Mixture

“…The process of crosslinking induced an increase in the contact angles of membranes. This can be attributed to the interaction of phosphoric acid with the hydrophilic groups of the polymers [17,25,28,29].…”