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One of the major biomedical problems facing worldwide is the diagnosis and treatment of tumor. This disease may lead to severe incidence with increased mortality rates. Therefore, it is the need of present era to develop advanced tools/methods for timely diagnosis of tumor. Aim of the present study is to evaluate the cytotoxicity and biodistribution of iron-oxide-stabilized zirconia (IOZH) nanoparticles with honey as a capping agent. In vivo-targeted diagnostic applications of stabilized ZrO2 nanoparticles are investigated through biodistribution of nanoparticles in rabbits. Nanoparticles (NPs) are synthesized using the microwave-assisted sol–gel method. Powers of microwave energy (100–900 W) are varied to synthesize stabilized zirconia NPs. Honey, as an organic capping agent, is added during synthesis. Structural results demonstrate the appearance of stabilized tetragonal phase of zirconia at 700 and 900 W without any further heat treatments. Smaller crystallite size of ~20 nm is observed for stabilized zirconia samples. Higher X-ray density is observed for pure tetragonal phase at 700 and 900 W. High dielectric constant (~55.8 at log f = 4) along with low tan loss is observed for zirconia prepared at 900 W. Magnetic results show superparamagnetic nature of the samples synthesized at 700 and 900 W. Radiolabeling along with biodistribution of iron-oxide-stabilized zirconia nanoparticles with technetium-99m is studied in normal rabbits. It is worth mentioning here that high-yield efficacy and stability along with its biodistribution and scintigraphy studies have been investigated. High uptake of radiotracer in bladder of rabbit is found to be potential candidate for its use in tumor therapies. Urination and physical properties of rabbit, after the post injection of nanoparticles, are checked periodically for many months and found normal.

Use of ceramic coatings has increased dramatically in orthopedics by improving their wear resistance and consequent long-term stability. Such stability involves not only the strength of material but also its resistance toward bacterial attacks. Amongst all ceramics, zirconia is selected in the present study due to its white color and high value of hardness making it a potential candidate to be used as implants and their coatings. In the present study effect of varying microwave powers (i.e. 100W, 200W, 300W, 400W, 500W, 600W, 700W, 800W, 900W and 1000W) on sol–gel synthesized glucose and fructose added zirconia coatings has been investigated. Formation of mixed tetragonal – monoclinic phases has been observed at relatively low microwave powers, i.e. 100–500W. However, at 600–1000W phase pure tetragonal zirconia is observed without any post heat treatment. FTIR analysis confirms formation of tetragonal phase of zirconia at 600–1000W microwave power. XPS results confirm the binding energies of Zr 3d and O 1s of microwave assisted zirconia coatings. High value of transmittance, i.e. ~90%, is observed at higher microwave powers. Variation in microwave powers is observed to tune the energy band gap of zirconia coatings in the range of 4.2–5.1 eV. Dielectric constant of 8–10 at log f = 4 is observed. High value of hardness and fracture toughness i.e. 1231 HV and 24.85 MPam−1/2, respectively, is observed for stabilized tetragonal zirconia coatings. Stabilized glucose fructose added zirconia shows strong antioxidant activity. Zirconia coatings are tested against Staphylococcus aureus bacteria for their potential application to treat bone infection. Results suggest that stabilized tetragonal zirconia can be successfully employed for orthopedic coatings.

Demand of bioactive materials that may create a bacteria-free environment while healing and regenerating the defect area is increasing day by day. Zirconia is a very interesting material because of its biocompatibility and high fracture toughness. In this research work, zirconia nanoparticles (NPs) have been synthesized using sol-gel method. Molarity of sols is varied in the range of 25 to 125 mM. The effect of acidic and basic nature of sols is studied by maintaining acidic (2) and basic (9) pH. As-synthesized NPs are made soluble in deionized (DI) water using tangerine drops. Dissolved NPs are spin coated onto glass substrate prior to characterization. Pure tetragonal phase, observed under all conditions using basic medium (pH 9), is accompanied by smaller crystallite size and unit cell volume. Presence of stabilized zirconia phase leads to higher value of density and higher mechanical strength. Nanodendrites with distinct features are observed for the sample prepared with high molarity using basic medium. Whereas, soft agglomerated nanodendrites are observed using acidic medium. Optical properties show transmission of 60–80% in the visible and infrared regions for acidic based samples and ~84% for basic samples. Direct energy band gap is varied from 4.96 eV to 5.1 eV in acidic (pH 2) and 4.91 eV to 4.97 eV in basic (pH 9) media. FTIR spectra show the formation of fundamental tetragonal band at 490 cm−1 for basic samples. Antibacterial response of zirconia is tested against E. coli, Streptococcus and Bacillus bacteria. Human teeth, bare and zirconia coated, are tested for their possible weight loss after dipping in various beverages. Zirconia coated tooth shows negligible degradation in hardness and weight after 24 hr dipping period. Thus, coatings prepared using water soluble zirconia (WSZ) nanoparticles, without the use of toxic solvents/reagents, are promising material to be used as protective coatings in biomedical applications.

It is well known that long term stability in zirconia has been a problem because of the structural alteration from stabilized tetragonal zirconia to monoclinic that leads to fracture in implants. Microwave (MW) assisted sol-gel synthesis is employed in the present work to prepare stabilize zirconia nanoparticles. ZrOCl2.8H2O is used as a precursor whereas de-ionized water is used as a solvent. Power of microwave radiations is varied in the range of 100–1000W. Zirconia nanoparticles have been characterized under as-synthesized, 6- and 12-months’ room temperature (RT) aged conditions. Metastable phase (MP) of zirconia, appearing under as-synthesized conditions, transforms to phase pure tetragonal zirconia (t-ZrO2) after RT aging that was prepared with MW powers of 100, 200 and 700–1000W. Whereas, MP transforms to mixed tetragonal-monoclinic phases at microwave powers of 300–600W after RT aging. XPS results show presence of oxygen-deficient state of ZrO2 lattice along with surface defects contributing towards the tetragonal zirconia phase under all conditions. Value of dielectric constant (i.e. ∼11–12 at log f = 4.0), hardness (∼1376 HV) and fracture toughness observed under all conditions are well in agreement to be used for biological implants. Disks of aged t-ZrO2 nanoparticles are checked for their biodegradation test by dipping in simulated body fluid for several weeks. ZrO2, with 26 weeks of immersion, shows small loss in hardness and weight. Stabilized tetragonal zirconia shows strong anti-oxidant activity. Stabilized ZrO2 nanoparticles presented strong antibacterial activity against both gram positive (S. aureus, Bacillus) and gram negative (E. coli) bacteria. Thus, structural and mechanical stability of zirconia (checked after 6 and 12 months) make this material highly beneficial for long term use in biomedical applications.