SUMMARY
Nanoparticles of silicates and germanates with a general formula Sr2R8–x–yErxYbyM6O26 (R = Y, La; M = Si, Ge) were produced in vacuum by the method of pulse electron beam evaporation. An upconversion photoluminescence of the nanoparticles was detected during the excitation by a laser with a wavelength of 980 nm with a predominance of lines in the red and near infrared regions of the spectrum. Due to their optical properties, the nanoparticles can be excited directly through the biotissues to visualize various pathologies. The obtained nanosamples have K-jumps of X-ray radiation absorption in the 10-100 keV energy region. This opens up prospects for the use of the nanoparticles as X-ray contrast agents. Thus, the nanoparticles have both optical and X-ray contrast characteristics, and therefore have the potential necessary for imaging and diagnosing pathologies in biological tissues.