International Journal of Nanomedicine (Feb 2020)
Silver-Containing Titanium Dioxide Nanocapsules for Combating Multidrug-Resistant Bacteria
Abstract
Nelly Hérault, 1,* Julia Wagner, 2–4,* Sarah-Luise Abram, 1 Jérôme Widmer, 2 Lenke Horvath, 1 Dimitri Vanhecke, 5 Carole Bourquin, 2–4,* Katharina M Fromm 1,* 1Department of Chemistry, University of Fribourg, Fribourg 1700, Switzerland; 2Department of Medicine, University of Fribourg, Fribourg 1700, Switzerland; 3Institute of Pharmaceutical Sciences of Western Switzerland, University of Geneva, Geneva 1211, Switzerland; 4Department of Anaesthesiology, Pharmacology, Intensive Care and Emergency Medicine, Faculty of Medicine, University of Geneva, Geneva 1211, Switzerland; 5Adolphe Merkle Institute, University of Fribourg, Fribourg 1700, Switzerland*These authors contributed equally to this workCorrespondence: Katharina M FrommUniversity of Fribourg, PER 10 bu. 114, chemin du Musée 9, Fribourg 1700, SwitzerlandTel +41 26 300 8732Email [email protected]: Joint arthroplasty has improved the quality of life of patients worldwide, but infections of the prosthesis are frequent and cause significant morbidity. Antimicrobial coatings for implants promise to prevent these infections.Methods: We have synthesized nanocapsules of titanium dioxide in amorphous or anatase form containing silver as antibacterial agent and tested their impact on bacterial growth. Furthermore, we explored the possible effect of the nanocapsules on the immune system. First, we studied their uptake into macrophages using a combination of electron microscopy and energy-dispersive spectroscopy. Second, we exposed immune cells to the nanocapsules and checked their activation state by flow cytometry and enzyme-linked immunosorbent assay.Results: Silver-containing titanium dioxide nanocapsules show strong antimicrobial activity against both E. coli and S. aureus and even against a multidrug-resistant strain of S. aureus. We could demonstrate the presence of the nanocapsules in macrophages, but, importantly, the nanocapsules did not affect cell viability and did not activate proinflammatory responses at doses up to 20 μg/mL.Conclusion: Our bactericidal silver-containing titanium dioxide nanocapsules fulfill important prerequisites for biomedical use and represent a promising material for the coating of artificial implants.Keywords: silver nanoparticles, titanium dioxide nanocapsules, antimicrobial effect, multidrug-resistant S. aureus, immune cell uptake
