چكيده به لاتين
Abstract
Hydroxyapatite is a major component of the hard tissues, such as bone and tooth, due to its good compatibility, bioavailability, and ability to interaction with bone. Different hydroxyapatite nanostructures are widely used in various medical fields, such as drug release systems, gene therapy, orthopedic and dental implants. Different methods and factors are used to control and modify the hydroxyapatite nanostructures. One of these methods is the use of organic compounds such as organic acids for the synthesis of hydroxyapatite nanoparticles.
In this study, the hydroxyapatite nanoparticles were characterized by the use of various organic acids such as oleic acid, acetic acid, and nitric acid as synthesis agent. The synthesized powders were analyzed by FE-SEM, XRD, FTIR and BET analyzes. The results of the scanning electron microscopy showed that among these chealating agents, nitric acid caused the formation of distinct needle-shaped apatite nanoparticles, which was considered as the optimum factor. In addition, the effect of temperature and pH on the morphology, structure and crystallinity of synthesized apatite nanoparticles was investigated using nitric acid chealating agent. The results of the characterization of synthesized apatite nanoparticles under ambient temperature and 90 °C, 120 °C and 140 °C indicate that the enhancement of temperature causes a change in the morphology of the needle-shaped apatite nanoparticles to the spheroidal shape and also observation of the maximum average crystallinity size at 90 °C. It was concluded that the decrease or increase in temperature compared with this temperature caused a loss of crystallinity. The results of the pH analysis showed that with the acidity of the environment, the needle morphology of the hydroxyapatite was broken up and the spherical shape has been created. On the other hand, in acidic and basic conditions, crystallite sizes were reduced and the highest crystallinity was obtained at pH 10. The results also showed that the change in temperature or pH has no special effect on the phase of synthesized apatites, and the nanoparticles had a hydroxyapatite phase without any impurities.
Keywords: hydroxyapatite¬ particles, organic acids, chealating agents, characteristics
