Inorganic Nanoparticles and Nanomaterials Based on Titanium (Ti): Applications in Medicine

Abstract

Nanomedicine is a relatively new field of science and technology. By interacting with biomolecules, therefore at nanoscale, nanotechnology opens up a vast field of research and application. Current and potential applications of nanotechnology in medicine range from research involving diagnostic devices, drug delivery vehicles to enhanced gene therapy and tissue engineering procedures. Its advantage over conventional medicine lies on its size. Operating at nanoscale allows to exploit physical properties different from those observed at microscale such as the volume/surface ratio. This allows drugs of nanosize be used in lower concentration and has an earlier onset of therapeutic action. It also provides materials for controlled drug delivery by directing carriers to a specific location. Inorganic nanomedicine is likely to remain one of the most prolific fields of nanomedicine, which refers to the use of inorganic or hybrid (inorganic-inorganic or inorganic-organic) nanomaterials (INMs) and nanoparticles (INPs) to achieve innovative medical advances for body parts implantation, drug and gene discovery and delivery, discovery of biomarkers, and molecular diagnostics. Among the most promising INMs being developed are metal, silica, dendrimers, organic-inorganic hybrids, ceramics (e.g. ZrO2, TiO2, Al2O3, etc.) and bioinorganic hybrids. Metal NP contrast agents enhance magnetic resonance imaging and ultrasound results in biomedical applications of in vivo imaging. Hollow and porous INMs have been exploited for drug and gene delivery, diagnostic imaging, and photothermal therapy. Biomolecular inorganic nanohybrids and nanostructured biomaterials have been exploited for targeted imaging and therapy, drug and gene delivery, and regenerative medicine. Potential uses for fluorescent quantum dots (QDs) include cell labeling, biosensing, in vivo imaging, bimodal magnetic-luminescent imaging, and diagnostics. Biocompatible QD conjugates have been used successfully for sentinel lymph node mapping, tumor targeting, tumor angiogenesis imaging, and metastasis cell tracking. This article outlines present developments and future prospects for the use of Ti-based NPs and NMs in experimental in vivo and in vitro studies and in engineering nanodevices and biosensors for clinical and investigative use in diagnosis and therapy in diverse fields of medical sciences, such as oncology, infection control, orthopedics, dentistry, dermatology, genetics, cardiology, ophthalmology, etc. Toxicological considerations of these INPs and INMs are also discussed.