Preparation and quality control of DTPA core-shell nanoparticles and optimization of its labeling conditions with gallium-68

The aim of this study was to investigate the effects of temperature and time and pH on the labeling of magnetic nanoparticles containing Gallium-68 radioisotope as a high-resolution imaging agent for PET/MRI imaging. Iron magnetic nanoparticles are prepared by a coherent method from a solution containing iron ions 1 and 2 in the presence of ammonium hydroxide, and then coated with silica to increase surface activity and protect nanoparticles against oxidation and to prevent the accumulation of particles (Stöber method). The core-shell nanoparticles were prepared by 3-amino-propyl tri-methoxy-silane (APTES), which has been formulated with amine groups and ultimately attached to the DTPA-causing agent. The use of DTPA results in the intrinsic in vivo stability of this complex. The particle size was measured on the basis of analyzes of about 30-40 nm. The nanoparticles were labeled with GaI-68 at pH =3/5 and the marking efficiency was measured by thin-layer chromatography. The optimum conditions for indicating the temperature of 60 °C and 30 minutes were determined.