Bacterial infections present an enormous problem causing human suffering and cost burdens to healthcare systems worldwide. Here we present novel tunable antibacterial coatings which completely inhibit bacterial colonization by Staphylococcus epidermidis but allow normal adhesion and spreading of osteoblastic cells. The coatings are based on amine plasma polymer films loaded with silver nanoparticles. The method of preparation allows flexible control over the amount of loaded silver nanoparticles and the rate of release of silver ions.

The manner by which plasma polymers grow in the very first stages of deposition is a topic which has been almost overlooked. We show using atomic force microscopy (AFM) and X‐ray photoelectron spectroscopy (XPS) that in the early stages of plasma deposition there are significant differences in the way plasma polymers grow from two amine‐containing compounds onto silicon wafers. By AFM it is shown that films grown from n‐heptylamine (HA) initially show ‘island‐like’ growth before a continuous smooth film is formed. In contrast, films from allylamine grow smoothly from the very earliest stages. XPS data show substantial differences of plasma polymer chemistry in close proximity to the silicon surface manifested in the formation of ${\rm NH}_{{\rm 3}}^{{\rm + }} $ and NOx species which are more abundant in films of HA. We present a possible explanation for these results based upon post‐plasma surface phenomena in the case of HA.

Ultrathin functional coatings deposited by plasma polymerization have utility in nano‐ and microtechnologies, however, until now very little has been reported to validate the widely held view that these coatings can be deposited onto any type of substrate, without substrate influence. In order to ascertain the role of the substrate in the early stages of plasma growth we address the growth rate and chemistry of plasma polymer coatings from two nitrogen‐ and two oxygen‐containing monomers during the first stages of deposition onto gold and onto thiol MUA‐coated gold surfaces. SPR thickness measurements and XPS analyzes indicate the substrate must be taken into account when ultrathin plasma polymer coatings are used for surface modification and we speculate on why this should be so.

This paper presents a novel and facile method for the generation of efficient antibacterial coatings which can be applied to practically any type of substrate. Silver nanoparticles were stabilized with an adsorbed surface layer of polyvinyl sulphonate (PVS). This steric layer provided excellent colloidal stability, preventing aggregation over periods of months. PVS-coated silver nanoparticles were bound onto amine-containing surfaces, here produced by deposition of an allylamine plasma polymer thin film onto various substrates. SEM imaging showed no aggregation upon surface binding of the nanoparticles; they were well dispersed on amine surfaces. Such nanoparticle-coated surfaces were found to be effective in preventing attachment of Staphylococcus epidermidis bacteria and also in preventing biofilm formation. Combined with the ability of plasma polymerization to apply the thin polymeric binding layer onto a wide range of materials, this method appears promising for the fabrication of a wide range of infection-resistant biomedical devices.

Carbon-based nanomaterials such as single-walled carbon nanotubes and reduced graphene oxide are currently being evaluated for biomedical applications including in vivo drug delivery and tumor imaging. Several reports have studied the toxicity of carbon nanomaterials, but their effects on human male reproduction have not been fully examined. Additionally, it is not clear whether the nanomaterial exposure has any effect on sperm sorting procedures used in clinical settings. Here, we show that the presence of functionalized single walled carbon nanotubes (SWCNT-COOH) and reduced graphene oxide at concentrations of 1–25 μg/mL do not affect sperm viability. However, SWCNT-COOH generate significant reactive superoxide species at a higher concentration (25 μg/mL), while reduced graphene oxide does not initiate reactive species in human sperm. Further, we demonstrate that exposure to these nanomaterials does not hinder the sperm sorting process, and microfluidic sorting systems can select the sperm that show low oxidative stress post-exposure.