Oxygen‐Deficient Bioceramics: Combination of Diagnosis, Therapy, and Regeneration

Abstract

The journey of ceramics in medicine has been synchronized with an evolution from the first generation—alumina, zirconia, etc.—to the third —3D scaffolds. There is an up‐and‐coming member called oxygen‐deficient or colored bioceramics, which have recently found their way through biomedical applications. The oxygen vacancy steers the light absorption toward visible and near infrared regions, making the colored bioceramics multifunctional—therapeutic, diagnostic, and regenerative. Oxygen‐deficient bioceramics are capable of turning light into heat and reactive oxygen species for photothermal and photodynamic therapies, respectively, and concomitantly yield infrared and photoacoustic images. Different types of oxygen‐deficient bioceramics have been recently developed through various synthesis routes. Some of them like TiO2−x, MoO3−x, and WOx have been more investigated for biomedical applications, whereas the rest have yet to be scrutinized. The most prominent advantage of these bioceramics over the other biomaterials is their multifunctionality endowed with a change in the microstructure. There are some challenges ahead of this category discussed at the end of the present review. By shedding light on this recently born bioceramics subcategory, it is believed that the field will undergo a big step further as these platforms are naturally multifunctional.

Designing of a Multifunctional 3D-Printed Biomimetic Theragenerative Aerogel Scaffold via Mussel-Inspired Chemistry: Bioactive Glass Nanofiber-Incorporated Self-Assembled Silk Fibroin with Antibacterial, Antiosteosarcoma, and Osteoinductive Properties

“…Among them, biomaterial-mediated thermal therapy for bone tumors is an emerging minimally invasive strategy based on generating local heat (41–47 °C) under external stimuli such as magnetism and light. In photothermal therapy (PTT) of bone tumors, biomaterials are usually incorporated with heat-generating agents such as near-infrared (NIR) agents, including metals (Au, Pt, Fe,...), − dopamine , carbon dots, , graphene oxide, , MXene, and black ceramics, , which upon stimulation with NIR laser can locally heat the tumor in the implantation site and maximize the retention of local heat without nonselective exposure to the normal tissues. , Most of these biomaterials, after the cancer therapy phase, have also demonstrated osteogenic functions promoting bone regeneration in the defect site in vivo. …”

Black Titania Janus Mesoporous Nanomotor for Enhanced Tumor Penetration and Near-Infrared Light-Triggered Photodynamic Therapy

“…Due to their excellent photoelectric characteristics, outstanding stability, and biocompatibility, TiO 2 nanomaterials are considered one of the most appropriate and competitive inorganic photosensitizers in PDT with demonstrated excellent therapeutic effects. − Nevertheless, owing to the intrinsic large band gap (3.0–3.2 eV), TiO 2 can only be stimulated under the ultraviolet spectrum of light, instead of the biological transparency near-infrared (NIR) biowindow (700–1100 nm) for PDT. − Consequently, much effort has been devoted to deal with this challenge. − Black hydrogenated titania (H-TiO 2– x ) with oxygen defects in the crystalline structure exhibits direct NIR light absorption property and efficient separation and transportation of photoexcited charges, thus having great potential in NIR light-triggered PDT. − …”

Photothermal Sensitive Nanocomposite Hydrogel for Infectious Bone Defects

“…These infections trigger inflammation, lead to tissue destruction, and severely impair the bone healing process [1][2][3] . The clinical treatments usually incorporate debridement and longtime use of antibiotics, which are heightened by the risk of severe complications and the growing concern of antibiotic resistance [4][5][6] . As a result, the final treatment process faces extended treatment times and diminished outcomes 7 .…”