Spectroscopy of nanoparticles based on Gd14B6Ge2O34 polycrystals and La2O3 — B2O3 glasses, activated by Nd3+ ions, for cancer diagnostics

Nanoparticles of gadolinium borate polycrystals and borate glasses, activated by Nd3+ ions, are obtained from macroscopic samples of the corresponding compositions by mechanical grinding and ultrasonic dispersion in water. A spectroscopic study of these nanoparticles in the near-IR region is performed to determine their potential as luminescence biosensors and radiopharmaceutical preparations for cancer diagnostics by radiosensitive methods. A twofold increase in the lifetime of the metastable ⁴F_3/2 state of Nd³⁺ ions at the transition from submicron polycrystalline particles to nanoparticles is experimentally found. A study of the nanoparticle distribution over organs and tissues of laboratory animals, performed with a 810-nm laser for exciting luminescence and a multichannel fibre spectrometer for measuring fluorescence in the range of 0.8 — 1.2 mm, showed this technique to be sufficiently sensitive to reliably determine the nanoparticle concentration in biological tissues and the dynamics of its change.