Interaction of Plasma Deposited HMDSO-Based Coatings with Fibrinogen and Human Blood Plasma: The Correlation between Bulk Plasma, Surface Characteristics and Biomolecule Interaction

Abstract

y These authors contributed equally.The success of a biomaterial depends on the nature of interaction and the progressive reaction between the biological components and the surface of the biomaterial. In order to control the interaction between the biomaterial and biological component, it is necessary to understand the factors that influence the protein adsorption and cell proliferation. Surface chemistry plays a crucial role in the success of any blood contacting biomaterial. Plasma enhanced chemical vapour deposition (PECVD) is an interesting commonly used technique for tailoring surface characteristics while retaining bulk material properties. Two different films, namely polymer-like and silica-like coatings, with varying surface characteristics have been deposited from hexamethyldisiloxane, by PECVD, on 316L stainless steel. A correlation between the bulk plasma, interfacial adhesion of the coating to 316L steel, surface characteristics and biomolecule interaction is presented in this work. The interfacial adhesion strength analysis demonstrated that silica-like coatings have higher adhesion strength to 316L stainless steel than polymer-like coatings, caused due to the formation of a strong FeÀOÀSi and ÀCrÀOÀSi bonds. It was observed that the effect of nanoscale surface roughness (close to 6 nm) was less significant, and that the surface chemistry played a significant role in governing the fibrinogen adsorption. Highest fibrinogen adsorption on plain steel was due to the electrostatic interaction of the metal oxide layer with the protein. Hydrophobicity of the polymer-like film resulted in a higher fibrinogen binding than the silicalike films.

Densification and Hydration of HMDSO Plasma Polymers

“…In fact, numerous reports in the literature have implicitly made use of the hydration of such nominally hydrophobic HMDSO coatings . For example, Saulou et al have shown that composite materials consisting of a pp‐HMDSO matrix with embedded silver nanoparticles act as anti‐microbial coatings.…”

“…HMDSO is widely used as a starting molecule for plasma polymers because it has a suitable vapor pressure at ambient conditions, is relatively non‐toxic and is commercially easily available. Numerous reports on its use in applications including pervaporation membranes, barrier coatings for controlled release of molecules, humidity sensors, biocompatible coatings, and anti‐bacterial nanosilver‐composite materials have been published . These examples suggest that plasma polymerized HMDSO films are stable in water and that (at least to some extent) water penetrates into these hydrophobic films (i.e., film hydration is possible).…”

Enhancement of Polymer Cytocompatibility by Nanostructuring of Polymer Surface

“…Depending on the gas used (Ar, He, Ne, N 2 , H 2 O, CO 2 , SO 2 , NH 3 , halogens, and their mixtures), the various types of functional groups are created on the polymer surface and the surface properties may be improved according to requirements of different applications [17]. The polymer surface chemistry, morphology, and biocompatibility [18][19][20][21][22] have been found to depend strongly on the type of plasma, plasma exposure time, and discharge power. Further modification of plasma-treated polymers may be accomplished by grafting of suitable molecules via covalent bonds to the polymer macromolecules [23].…”

Inspired Chemistry for a Simple but Highly Effective Immobilization of Vascular Endothelial Growth Factor on Gallic Acid‐functionalized Plasma Polymerized Film

“…The approach reported in this work firstly involves the deposition of plasma polymerized allylamine (PPAam) thin film onto a substrate to introduce the amine groups (Figure 1a). 21 In recent years there has been rapidly increasing interest in the deposition of plasma polymerized organic thin films to modify bulk materials,21–26 because these thin, homogeneous, and pinhole‐free films contain reactive groups, and provide good surface coverage and adherent strength onto a wide range of different substrates. Gallic acid (3,4,5‐trihydroxybenzoic acid, GA) (Figure 1b) is a polyphenyl natural product from plants.…”