Dose‐dependent surface endothelialization and biocompatibility of polyurethane noble metal nanocomposites

Abstract

Surface pre-endothelialization is a promising approach to improve the hemocompatibility of implants, medical devices, and artificial organs. To promote the adhesive property of thermoplastic polyurethane (TPU) for endothelial cells (ECs), up to 1 wt % of gold (Au) or platinum (Pt) nanoparticles, fabricated by pulsed laser ablation in polymer solution, were embedded into the polymer matrix. The analysis of these nanocomposites showed a homogenous dispersion of the nanoparticles, with average diameters of 7 nm for Au or 9 nm for Pt. A dose-dependent effect was found when ECs were seeded onto nanocomposites comprising different nanoparticle concentrations, resulting in a fivefold improvement of proliferation at 0.1 wt % nanoparticle load. This effect was associated with a nanoparticle concentration-dependent hydrophilicity and negative charge of the nanocomposite. In dynamic flow tests, nanocomposites containing 0.1 wt % Au or Pt nanoparticles allowed for the generation of a confluent and resistant EC layer. Real-time polymerase chain reaction quantification of specific markers for EC activation indicated that ECs cultivated on nanocomposites remain in an inactivated, nonthrombogenic and noninflammatory state; however, maintain the ability to trigger an inflammatory response upon stimulation. These findings were confirmed by a platelet and leukocyte adhesion assay. The results of this study suggest the possible applicability of TPU nanocomposites, containing 0.1 wt % Au or Pt nanoparticles, for the generation of pre-endothelialized surfaces of medical devices.

Antimicrobial efficacy, cytotoxicity, and ion release of mixed metal (Ag, Cu, Zn, Mg) nanoparticle polymer composite implant material

“…As an example, homogeneously distributed silver nanoparticles in TPU are shown in Figure 4E. For noble metals like gold, platinum, silver or copper, pulsed laser ablation in liquid results in metal nanoparticles and no indication of bulk oxidation [40], with plasmon resonance spectra typical for elemental silver and copper nanoparticles and high ion-release capacities [27]. During laser ablation of base metals like magnesium or zinc in organic solvents, partial oxidation of the nanoparticles cannot be excluded, although nanocomposites with elemental magnesium embedded in a polymer have been fabricated recently by this method [41].…”

Effect of Pt/C addition to TiO2 films on adhesion and rapid light-induced detachment of mammalian cell cultures

“…A similar cell response occurred on the pure TiO 2 films and the Pt/C-TiO 2 composite films, because the two kinds of films had almost the same characteristics in surface morphology. Better cell adhesion and proliferation for PCT-4 films may be attributed to the dose-dependent effect of Pt [26] coupled with more graphite amounts which was demonstrated to strongly stimulate cell adhesion and proliferation [27,28]. Interestingly, recent study also reported that filopodia of osteoblast cells inclined to move towards and got anchored by graphene, which in turn facilitated the spreading and subsequent proliferation of the cells [29].…”

Process Chain for the Fabrication of Nanoparticle Polymer Composites by Laser Ablation Synthesis

“…4 a). Note that Hess et al [57] achieved fivefold improvement of nanocomposite biofunctionality already at an AuNP doping level of 0.1 wt %. Fig.…”