AQUEOUS DISPERSION BASED ON NANOPARTICLES OF TANTALUM OXIDE, METHOD OF PRODUCING AND USE THEREOF AS CONTRAST AGENT FOR IN VIVO DIAGNOSIS Russian patent published in 2020 - IPC B22F9/24 B22F1/00 

FIELD: chemistry.

SUBSTANCE: group of inventions relates to the chemical-pharmaceutical industry and involves preparing an aqueous dispersion based on nanoparticles of tantalum oxide, aqueous dispersion and use thereof as an X-ray contrast agent for computed tomography. Alcohol dispersion of nanoparticles of tantalum oxide TaO_x, where x is from 1 to 2.5, with particle size of 2–6 nm is obtained by mixing tantalum ethylate with an organic solvent in the form of isopropyl or propyl alcohol and holding mixture for 10–12 hours at temperature of 200–220 °C with heating rate 2 °C/min. Obtained alcohol dispersion of the nanoparticles is added to the aqueous medium with vigorous stirring, the organic solvent is slowly evaporated at temperature of 65–75 °C and pH of dispersion is 5–7. Obtained aqueous dispersion of nanoparticles is subjected to ultrasonic treatment for 0.5–3 hours. Aqueous dispersion of the solid phase is 0.2–2 wt. %, the aggregates of the tantalum oxide particles have an average hydrodynamic diameter of 64–147 nm, and the electrokinetic potential of the dispersion ranges from −52 mV to −35 mV.

EFFECT: providing high sedimentation and aggregation resistance of the dispersion for a long period of time and widening the range of products for contrasting.

3 cl, 2 tbl, 15 dwg, 20 ex