Preparation and characterization of hydroxyapatite nanoparticles doped with nickel, tin, and molybdate ions for their antimicrobial effects.

BACKGROUND: Hydroxyapatite (HAp) nanoparticles doped with some ions have shown anticancer and antibacterial properties and are of great interest for the development of new biomedical applications. Therefore, the present study aimed to investigate the preparation and in vitro characterization of HAp nanoparticles doped with (Ni2+), tin (Sn2+), molybdate (Mo3+) ions for prevention of infections specially in bone tissue engineering. METHODS: HAp and HAp nanocrystal powders doped with nickel (Ni2+), tin (Sn2+), molybdate ions (Mo3+) with concentrations of 500, 1000, and 2000 ppm were prepared by the sol-gel method using a combination of calcium nitrate and phosphorous pentoxide as chemical reagents. The nanoparticles were characterized by FT-IR, XRD, EDAX and SEM. Their antimicrobial effect was studied by disk diffusion method on two types of bacteria: Pseudomonas aeruginosa and Staphylococcus aureus. RESULTS: FT-IR and XRD tests confirmed the formation of HAp nanoparticles. SEM images showed the morphology and nanostructure of HAp and Ni@HAp. Ni@HAp showed significantly more antimicrobial effects than the other two ions on S. aureus. EDAX confirmed the presence of Ni2+ ions in the Ni@HAp structure and the element map also showed very good dispersion of elements in both HAp and Ni@HAp structures. CONCLUSIONS: HAp nanoparticles doped with nickel ions may be considered as a promising antibacterial treatment in bone tissue engineering and repairing of skeletal injuries contaminated with S. aureus.

Plasma Cytokines Profile in Subjects with Alzheimer's Disease: Interleukin 1 Alpha as a Candidate for Target Therapy.

Background: Testicular function depends on temperature, and it has been shown that scrotal hyperthermia causes a sharp decrease in sperm parameters due to oxidative stress. In recent years, the use of natural materials from the plant and nanoparticles has attracted much attention. Therefore, the present study aimed to investigate the effect of curcumin and Fe2O3 nanoparticles on sperm parameters in rats. Materials and Methods: After preparing the rats, they were placed in a hot water bath at 43°C for 30 minutes for six consecutive days. The 48 rats were then divided into eight groups. A concentration of 0.03 mg/kg body weight magnetic Fe2O3 nanoparticles and curcumin at the concentration of 0.02 mg/kg body weight were used. After killing animals, the semen parameters such as viability, concentration, motility, and morphology of sperm were studied. Results: Significant differences were observed in all groups of rats in terms of semen parameters (P<0.001). The results showed a positive effect of curcumin on improving semen parameters in scrotal hyperthermia rats and a negative and toxic effect of Fe2O3 magnetic nanoparticles. However, significant improvement in sperm parameters was observed when Fe2O3 magnetic nanoparticles were given to rats along with curcumin. Conclusion: Curcumin has a positive and significant effect on improving sperm parameters in scrotal hyperthermia conditions. Fe2O3 magnetic nanoparticles, if co-administered with curcumin, can significantly improve sperm parameters. In this regard, green synthesis of nanoparticles and concomitant administration of antioxidants such as curcumin in scrotal hyperthermia conditions is recommended.