Hydroxyapatite Decorated with Tungsten Oxide Nanoparticles: New Composite Materials against Bacterial Growth

Abstract

The availability of biomaterials able to counteract bacterial colonization is one of the main requirements of functional implants and medical devices. Herein, we functionalized hydroxyapatite (HA) with tungsten oxide (WO3) nanoparticles in the aim to obtain composite materials with improved biological performance. To this purpose, we used HA, as well as HA functionalized with polyacrilic acid (HAPAA) or poly(ethylenimine) (HAPEI), as supports and polyvinylpyrrolidone (PVP) as stabilizing agent for WO3 nanoparticles. The number of nanoparticles loaded on the substrates was determined through Molecular Plasma-Atomic Emission Spectroscopy and is quite small, so it cannot be detected through X-ray diffraction analysis. It increases from HAPAA, to HA, to HAPEI, in agreement with the different values of zeta potential of the different substrates. HRTEM and STEM images show the dimensions of the nanoparticles are very small, less than 1 nm. In physiological solution HA support displays a greater tungsten cumulative release than HAPEI, despite its smaller loaded amount. Indeed, WO3 nanoparticles-functionalized HA exhibits a remarkable antibacterial activity against the Gram-positive Staphylococcus aureus in absence of cytotoxicity, which could be usefully exploited in the biomedical field.

Cellulose acetate membranes loaded with combinations of tetraphenylporphyrin, graphene oxide and Pluronic F-127 as responsive materials with antibacterial photodynamic activity

“…This feature has been previously reported for other biomaterials having antibacterial activity via ROS production. 38 It can be noticed that the membrane containing all the three additives, TPP, GO and the surfactant, showed the highest activity against both types of bacteria compared to the other experimental conditions (with signicant differences associated to p < 0.0001). This result can be ascribed to the combination of photoinduced effects (production of singlet oxygen and other ROS) and morphological characteristics of the membrane imparted by the presence of the surfactant.…”

Mutant-Dependent Local Orientational Correlation in Biofilms of Vibrio campbellii Revealed through Digital Processing of Light Microscopy Images

“…Hydroxyapatite multicomponent systems are widely used in the medical field due to inertness, long-term life, biocompatibility, and possibility to modify bacterial adherence and enhance antibacterial surface activity through nanostructuring as well as through doping/coating with metal ions (Mg 2+ , Sr 2+ , Zn 2+ , Cu 2+ , Ag + ) or functionalization with antibiotics [ 49 , 50 ]. We considered pristine HA to be an ideal inert substrate with no impact on the growth of the biofilm; hence, the role of the mutants could be highlight at best.…”

Cellulose/Zeolitic Imidazolate Framework (ZIF-8) Composites with Antibacterial Properties for the Management of Wound Infections

“…In this study, the cellular response to the Cell@ZIF-8 composites was tested in double-chambered 12-well plates. Each well has a permeable PET-membrane suitable for drug transport studies [53] that separates the cell monolayer (in the lower chamber) from The antibacterial property of the ZIF-8 crystals was finally examined by applying the agar cup diffusion method. The ZIF-8 samples proved to have excellent antimicrobial effect (Table S2) regardless of the activation procedure and a concentration-dependent inhibitory activity was measured, indicating that the bactericidal effect of ZIF-8 is due to the dissolution of zinc ions in the medium instead of the released and associated pH increase of 2-HmIM [34].…”