Determination, Modeling and Evaluation of Kinetics of 223Ra Sorption on Hydroxyapatite and Titanium Dioxide Nanoparticles

Abstract

Sorption kinetics of radium on hydroxyapatite and titanium dioxide nanomaterials were studied. The main aim of the current study was to determine the rate-controlling process and the corresponding kinetic model, due to the application of studied nanomaterials as α-emitters’ carriers, and to assess the sorption properties of both materials from the radiopharmaceutical point of view by time regulated sorption experiments on the nanoparticles. Radium-223 was investigated as radionuclide used in targeted alpha particle therapy as an in vivo generator. It was found that the controlling process of the 223Ra sorption kinetics was the diffusion in a reacted layer. Therefore, parameters like particle size, their specific surface area, contact time and temperature played important role. Moreover, the composition of liquid phase, such as pH, the concentration of 223Ra, ionic strength, the presence of complexation ligands, etc., had to be considered. Experiments were conducted under free air conditions and at pH 8 for hydroxyapatite and pH 6 for titanium dioxide in Britton–Robinson buffer. Initial 223Ra concentration was in the range from 10−11 to 10−12 mol/L. It was found that sorption kinetics was very fast (more than 90% in the first hour) in the case of both nanomaterials, so they can be directly used for efficient radium sorption.

Hydroxyapatite and Titanium Dioxide Nanoparticles: Radiolabelling and In Vitro Stability of Prospective Theranostic Nanocarriers for 223Ra and 99mTc

“…However, the difference was statistically undetectable. It is important to note that all the results correspond with earlier published data from sorption and kinetic studies [ 38 , 39 ].…”

“…This work develops the already-published results by Kukleva et al [ 15 ], Suchánková et al [ 38 ] and Suchánková et al [ 39 ]. The main interest in the current paper was given to 223 Ra labelling due to its therapeutic properties.…”

“…Although the released activities from 223 Ra- n HAp were relatively high, it is still a promising carrier according to serum stability results. Previously published results [ 15 , 38 , 39 ] showed that both materials are suitable as carriers and both radiolabelling strategies showed high radiolabelling yields for inorganic nanomaterials.…”

Preclinical and Clinical Status of PSMA-Targeted Alpha Therapy for Metastatic Castration-Resistant Prostate Cancer

“…Unfortunately, 223 Ra, like other alkaline earth metals, forms very weak complexes [160,161]. To overcome this limitation, several nanomaterials, hydroxyapatites, polyoxopalladates, nanozeolites, barium sulfate, and titanium dioxide nanoparticles have been tested for stable incorporation of radium and linking to the targeting vector [84,[162][163][164][165][166]. So far, only one paper has been published investigating the encapsulation of 223 Ra into functionalized nanozeolites for PSMA-TAT [84].…”

In vitro studies of 223Ra- and 225Ac-labelled α-zirconium phosphate as potential carrier for alpha targeted therapy

“…Various nanoparticles (NPs) including TiO 2 [7] Hydroxyapatite [7], SPIONs [8], Nanozeolite A [9] or reduced graphite oxide [10] were labelled with 223 Ra. In these studies, radionuclide immobilisation and release activity of 223 Ra were monitored.…”