Preparation Of Octacalcium Phosphate (OCP) And Tricalcium Phosphate (TCP) Nanoparticles In Microemulsion

Octacalcium phosphat(eCa₈(HPO₄)₂(PO₄)·5H₂O,OCP) which is one of the main components of teeth and bones is an important precursor of hydroxyapatite and a good bone replacement material,and it has good biocompatibility and biological activity; Calcium phosphate(Ca3(PO4)2,TCP) has a similar composition to mineral composition of human bone tissue,and it has good biodegradability, biocompatibility and biological non-toxic. After TCP is implanted in the human body, the Ca and P of degradation can enter the circulatory system in vivo resulting in the formation of new bone. Octacalcium phosphate and tricalcium phosphate used as a tissue repair material have a good application prospect in terms of bone repair. Different preparation methods has an important impact on application and performance of the two.Microemulsion method is a new method for preparation of nanoparticles,because it can control size, morphology and surface area of the particle, etc,so that it is a lot of attention by people. In this study,nanopowders of OCP and TCP are synthesized by reverse microemulsion.In the study , triton X-100/1-decanol/isooctane/water phase diagram of four-component system is made. This paper adopts research methods of the combination of visual and electrical conductivity measurement, studys the structure of triton X-100/1-decanol/isooctane/water phase diagram of four-component system and discusses the effects of different oil,different proportions of triton X-100 and 1-decanol,different concentrations and different reaction temperatures on the system of W/O structure of the most water solution and system stability. It determines the reverse microemulsion method to make phase diagram region of nano octacalcium phosphate and nano calcium phosphate. Useing microemulsion of this area as a template,by changing the different reaction conditions, successfully synthesize the OCP and TCP nanoparticles with different size and morphology.Size,structure and morphology of the product particles are studied by characterization methods of transmission electron microscopy (TEM),X-ray diffraction (XRD),infrared spectroscopy (FTIR). Among them, OCP is the rod-like nano-particles, a diameter of 20⁵0nm, a length of 60¹20nm; TCP is the spindle nano-particles, a diameter of 10 20nm, a length of 80 110nm.What it is discussed is that the different heat treatment temperatures,different water-oil ratio and different aging time,different mixing time and different pH values of the solution have impact on morphology,size and degree of crystallinity of OCP and TCP nano-particles. The results show that OCP and TCP nano-particle size can be controlled by changes in water-oil ratio and stirring time, but the aging time has little impact on them, and the change of solution pH will lead to changes in the final product.