Semi-automated system for concentrating Ga-68-eluate to obtain high molar and volume concentration of Ga-68-Radiopharmaca for preclinical applications
| Autor: | Ho Sze Chan, Elisabeth Oehlke, Erik de Blois, Wouter A.P. Breeman, Rory M. S. de Zanger |
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| Přispěvatelé: | Radiology & Nuclear Medicine |
| Rok vydání: | 2018 |
| Předmět: |
Molar
Cancer Research Chromatography Chemistry Elution High-performance liquid chromatography 030218 nuclear medicine & medical imaging Metal 03 medical and health sciences Chelex 100 chemistry.chemical_compound 0302 clinical medicine Volume (thermodynamics) 030220 oncology & carcinogenesis Yield (chemistry) visual_art Peek visual_art.visual_art_medium Molecular Medicine Radiology Nuclear Medicine and imaging |
| Zdroj: | Nuclear Medicine and Biology, 64-65, 16-21. Elsevier Inc. |
| ISSN: | 1872-9614 0969-8051 |
| Popis: | Introduction 68Ga-radiopharmaceuticals are common in the field of Nuclear Medicine to visualize receptor-mediated processes. In contrast to straightforward labeling procedures for clinical applications, preclinical in vitro and in vivo applications are hampered for reasons like e.g. volume restriction, activity concentration, molar activity and osmolality. Therefore, we developed a semi-automatic system specifically to overcome these problems. A difficulty appeared unexpectedly, as intrinsic trace metals derived from eluate (Zn, Fe and Cu) are concentrated as well in amounts that influence radiochemical yield and thus lower molar activity. Methods To purify Gallium-68 and to reduce the high elution volume of a 68Ga-generator, a NaCl-based method using a column containing PS-H+ was implemented in a low volume PEEK system. Influence on reducing osmolality, acidity and the amount of PS-H+ resin (15–50 mg) was investigated. [68Ga]Ga was desorbed from the PS-H+ resin with acidified 2-5 M NaCl (containing 0.05 M of HCl) and 68Ga-activity was collected. DOTA-TATE was used as a peptide model. All buffers and additives used for labeling were mixed with Chelex 100 (~1 g/50 mL) for >144 h and eventually filtered using a 0.22 μm filter (Millipore). Quantification of metals was performed after labeling by HPLC (UV). Results Gallium-68 activity could be desorbed from PS-H+ cation column with 3 M NaCl, and >60% (120–180 MBq) of [68Ga]Ga was collected in 99% (ITLC), and a radiochemical purity of >95% (HPLC). Conclusion With the here described concentration system and metal purification technique, a low activity containing 68Ga-generator can be used to label DOTA-peptide in preclinical applicable amounts >60 MBq/nmol (40–60 MBq/0.1 mL) and within 20 min. |
| Databáze: | OpenAIRE |
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