nanomaterials Review Titanium Dioxide Nanoparticles: Prospects and Applications in Medicine Daniel Ziental 1 , Beata Czarczynska-Goslinska 2, Dariusz T. Mlynarczyk 3 , Arleta Glowacka-Sobotta 4, Beata Stanisz 5, Tomasz Goslinski 3,* and Lukasz Sobotta 1,* 1 Department of Inorganic and Analytical Chemistry, Poznan University of Medical Sciences, Grunwaldzka 6, 60-780 Poznan, Poland;
[email protected] 2 Department of Pharmaceutical Technology, Poznan University of Medical Sciences, Grunwaldzka 6, 60-780 Poznan, Poland;
[email protected] 3 Department of Chemical Technology of Drugs, Poznan University of Medical Sciences, Grunwaldzka 6, 60-780 Poznan, Poland;
[email protected] 4 Department and Clinic of Maxillofacial Orthopedics and Orthodontics, Poznan University of Medical Sciences, Bukowska 70, 60-812 Poznan, Poland;
[email protected] 5 Department of Pharmaceutical Chemistry, Poznan University of Medical Sciences, Grunwaldzka 6, 60-780 Poznan, Poland;
[email protected] * Correspondence:
[email protected] (T.G.);
[email protected] (L.S.) Received: 4 January 2020; Accepted: 19 February 2020; Published: 23 February 2020 Abstract: Metallic and metal oxide nanoparticles (NPs), including titanium dioxide NPs, among polymeric NPs, liposomes, micelles, quantum dots, dendrimers, or fullerenes, are becoming more and more important due to their potential use in novel medical therapies. Titanium dioxide (titanium(IV) oxide, titania, TiO2) is an inorganic compound that owes its recent rise in scientific interest to photoactivity. After the illumination in aqueous media with UV light, TiO2 produces an array of reactive oxygen species (ROS). The capability to produce ROS and thus induce cell death has found application in the photodynamic therapy (PDT) for the treatment of a wide range of maladies, from psoriasis to cancer.