| Abstract [eng] |
Titanium oxide is used in many personal care products as: toothpastes, sunscreens, pressed and loose powders, day creams and lip balms, as an inorganic UV filter/absorber or bleaching agent. Currently, the only form in which titanium oxide is used in cosmetics – titanium oxide nanoparticles [1]. Calcium phosphates have good biodegradability, compatibility, bioresorption and osteoinductivity. Calcium phosphates such as hydroxyapatite is major component of bone tissue and used in the cosmetic industry [2]. The aim of this work was to investigate the influence of titanium oxide on the formation of hydroxyapatite. In this work, titanium oxide, calcium carbonate and ammonium hydrophosphate were used as the main raw materials in the microwave synthesis of hydroxyapatite. The dry primary mixture of calcium carbonate and titanium dioxide was mixed with ammonium hydrophosphate, with a molar ratio of Ca/P=1,67 was mixed with distilled water to reach a solution/solid ratio of the suspension of 10:1. The microwave synthesis has been carried out in unstirred suspensions under saturated steam pressure at the temperature of 80-200 °C for 2 h. XRD, DSC, TG, and FT-IR methods were used to characterize the products of synthesis. It was found that in the CaCO3-(NH4)2HPO4-TiO2-H2O system the raw materials, e.g. TiO2 (d-spacing – 0.352; 0.189; 0.238 nm (PDF 00-021-1272)) and CaCO3 (d-spacing – 0.304; 0.229; 0.210; 0.191; 0.188 nm (PDF 04-023-8700)) react poorly at a temperature of 80 oC. In the products of synthesis low intensity peaks were identified which are assigned to target product - hydroxyapatite (d-spacing – 0.282; 0.273; 0.278; 0.819; 0.194 (PDF 01-082-1943)). Meanwhile, it was determined that the increment of microwave synthesis temperature had a positive influence on the interaction of raw materials with intermediate synthesis compounds (Fig. 1). |
