Holmium Nanoparticles: Preparation and In Vitro Characterization of a New Device for Radioablation of Solid Malignancies

• Published in: Pharmaceutical research 2010-10, Vol.27 (10), p.2205-2212
• Main Authors: Bult, Wouter, Varkevisser, Rosanne, Soulimani, Fouad, Seevinck, Peter R., de Leeuw, Hendrik, Bakker, Chris J. G., Luijten, Peter R., van het Schip, Alfred D., Hennink, Wim E., Nijsen, J. Frank W.
• Format: Article
• Language: English
• Subjects: Ablation Techniques - instrumentation; Ablation Techniques - methods; Biochemistry; Biological and medical sciences; Biomedical and Life Sciences; Biomedical Engineering and Bioengineering; Biomedicine; Cancer; Chemical elements; General pharmacology; Holmium - administration & dosage; Holmium - chemistry; Humans; Injections, Intralesional; Medical Law; Medical sciences; Microscopy, Electron, Scanning; Nanoparticles; Nanoparticles - administration & dosage; Nanoparticles - chemistry; Neoplasms - radiotherapy; Particle Size; Pharmaceutical sciences; Pharmaceutical technology. Pharmaceutical industry; Pharmacology. Drug treatments; Pharmacology/Toxicology; Pharmacy; Radiation therapy; Radioisotopes; Research Paper; Spectroscopy, Fourier Transform Infrared; Surface Properties
• ISSN: 0724-8741; 1573-904X
• DOI: 10.1007/s11095-010-0226-3

ABSTRACT Purpose The present study introduces the preparation and in vitro characterization of a nanoparticle device comprising holmium acetylacetonate for radioablation of unresectable solid malignancies. Methods HoAcAc nanoparticles were prepared by dissolving holmium acetylacetonate in chloroform, followed by emulsification in an aqueous solution of a surfactant and evaporation of the solvent. The diameter, surface morphology, holmium content, and zeta potential were measured, and thermal behavior of the resulting particles was investigated. The stability of the particles was tested in HEPES buffer. The r 2 * relaxivity of protons and mass attenuation coefficient of the nanoparticles were determined. The particle diameter and surface morphology were studied after neutron activation. Results Spherical particles with a smooth surface and diameter of 78 ± 10 nm were obtained, and the particles were stable in buffer. Neutron irradiation did not damage the particles, and adequate amounts of activity were produced for nuclear imaging and radioablation of malignancies through intratumoral injections. Conclusions The present study demonstrates that HoAcAc nanoparticles were prepared using a solvent evaporation process. The particle diameter can easily be adapted and can be optimized for specific therapeutic applications and tumor types.