Search results for "Gallium Radioisotopes"

AMD3100: A Versatile Platform for CXCR4 Targeting 68 Ga-Based Radiopharmaceuticals

2016

International audience; CXCR4 is a G protein-coupled receptor (GPCR), which is overexpressed in numerous diseases, particularly in multiple cancers. Therefore, this receptor represents a valuable target for imaging and therapeutic purposes. Among the different approaches, which were developed for CXCR4 imaging, a CXCR4 antagonist biscyclam system (AMD3100, also called Mozobil), currently used in the clinic for the mobilization of hematopoietic stem cells, was radiolabeled with different radiometals such as 62Zn, 64Cu, 67Ga, or 99mTc. However, cyclam is not an ideal chelator for most of these radiometals, and could lead to the release of the radionuclide in vivo. In the current study, a new …

Diagnostic Performance of 68Ga-PSMA-11 Positron-emission-tomography/Computed-tomography in a Large Cohort of Patients with Biochemical Recurrence of …

2020

Gallium-68 (Ga) prostate-specific-membrane-antigen positron-emission-tomography/computed-tomography is a highly promising method for imaging primary and recurrent prostate cancer. These dual-modality imaging technologies enable whole-body functional and anatomical evaluation in a single session. This study investigated the performance of Ga-prostate-specific-membrane-antigen-11 positron-emission-tomography/computed-tomography for detecting prostate carcinoma in patients with rising prostate-specific-antigen after primary therapy. Six hundred sixty (660) patients with biochemical recurrence referred for positron-emission-tomography/computed-tomography with Ga-prostate-specific-membrane-antig…

Validation of (68)Ge/(68)Ga generator processing by chemical purification for routine clinical application of (68)Ga-DOTATOC.

2008

Abstract Introduction Imaging of somatostatin receptor expressing tumours has been greatly enhanced by the use of 68 Ga-DOTATOC and PET/CT. Methods In this work, a purification method for the 68 Ge/ 68 Ga generator eluate and a method to produce 68 Ga-DOTATOC suitable for clinical use were evaluated. The generator eluate was purified and concentrated on a cation-exchange cartridge in HCl/acetone media. The efficacy of this procedure in eliminating metal impurities from the 68 Ga solution was investigated by ICP-MS. The radiotracer quality was evaluated by radio-TLC, GC and γ-ray spectrometry. Results 68 Ga-DOTATOC preparations ( n =33) were carried out with a mean synthesis yield of 59.3±2.…

Processing of Generator-Produced 68Ga for Medical Application

2007

The (68)Ge/(68)Ga generator provides an excellent source of positron-emitting (68)Ga. However, newly available "ionic" (68)Ge/(68)Ga radionuclide generators are not necessarily optimized for the synthesis of (68)Ga-labeled radiopharmaceuticals. The eluates have rather large volumes, a high concentration of H(+) (pH of 1), a breakthrough of (68)Ge, increasing with time or frequency of use, and impurities such as stable Zn(II) generated by the decay of (68)Ga, Ti(IV) as a constituent of the column material, and Fe(III) as a general impurity.We have developed an efficient route for the processing of generator-derived (68)Ga eluates, including the labeling and purification of biomolecules. Prec…

[68Ga]Ga-DATA5m.SA.FAPi PET/CT: Specific Tracer-uptake in Focal Nodular Hyperplasia and potential Role in Liver Tumor Imaging.

2020

Spectroscopic, radiochemical, and theoretical studies of the Ga3+-N-2-hydroxyethyl piperazine-N'-2-ethanesulfonic acid (HEPES buffer) system: evidenc…

2013

Recent reports have claimed a superior performance of HEPES buffer in comparison to alternative buffer systems for 67/68 Ga labeling in aqueous media. In this paper we report spectroscopic (1H and 71 Ga NMR), radiochemical, mass spectrometry and theoretical modeling studies on the Ga3+/HEPES system (HEPES = N-2-hydroxyethylpiperazine-N′-2-ethanesulfonic acid) performed with the aim of elucidating a potential contribution of HEPES in the 68/67 Ga radiolabeling process. Our results demonstrate that HEPES acts as a weakly but competitive chelator of Ga3+ and that this interaction depends on the relative Ga3+: HEPES concentration. A by-product formed in the labeling mixture has been identified …

Gallium-68 and scandium-44 labelled radiotracers based on curcumin structure linked to bifunctional chelators: Synthesis and characterization of pote…

2019

Abstract Curcumin metal complexes showed widespread applications in medicine and can be exploited as a lead structure for developing new tracers for nuclear medicine application. Herein, the synthesis, chemical characterization and radiolabelling with gallium-68 and scandium-44 of two new targeting vectors based on curcumin scaffolds and linked to the chelators 1,4,7-triazacyclononane,1-glutaric acid-4,7-acetic acid (NODAGA) and 1,4-bis(carboxymethyl)-6-[bis(carboxymethyl)]amino-6-methylperhydro-1,4-diazepine (AAZTA) are reported. Synthesis of the precursors could be achieved with a 13% and 11% yield and radiolabelling generally afforded rapid incorporation under mild conditions (>95%). Sta…

In vivo comparison of DOTA based 68Ga-labelled bisphosphonates for bone imaging in non-tumour models.

2013

Bone metastases are a class of cancerous metastases that result from the invasion of a tumor into bone. The solid mass which forms inside the bone is often associated with a constant dull ache and severe spikes in pain, which greatly reduce the quality of life of the patient. Numerous (99m)Tc-labeled bisphosphonate functionalised complexes are well established tracers for bone metastases imaging. The objective of this research was to evaluate the pharmacokinetics and behaviour of three DOTA based bisphosphonate functionalised ligands (BPAMD, BPAPD and BPPED), using both (68)Ga μ-PET in vivo imaging and ex vivo biodistribution studies in healthy Wistar rats. The compounds were labelled with …

68Ge/68Ga Generators: Past, Present, and Future

2012

In 1964, first (68)Ge/(68)Ga radionuclide generators were described. Although the generator design was by far not adequate to our today's level of chemical, radiopharmaceutical and medical expectations, it perfectly met the needs of molecular imaging of this period. (68)Ga-EDTA as directly eluted from the generators entered the field of functional diagnosis, in particular for brain imaging. A new type of generators became commercially available in the first years of the 21st century. Generator eluates based on hydrochloric acid provided "cationic" (68)Ga instead of "inert" (68)Ga-complexes and opened new pathways of Me(III) based radiopharmaceutical chemistry. The impressive success of util…

(R)-NODAGA-PSMA: A Versatile Precursor for Radiometal Labeling and Nuclear Imaging of PSMA-Positive Tumors

2015

Purpose The present study aims at developing and evaluating an urea-based prostate specific membrane antigen (PSMA) inhibitor suitable for labeling with 111In for SPECT and intraoperative applications as well as 68Ga and 64Cu for PET imaging. Methods The PSMA-based inhibitor-lysine-urea-glutamate-coupled to the spacer Phe-Phe-D-Lys(suberoyl) and functionalized with the enantiomerically pure prochelator (R)-1-(1-carboxy-3-carbotertbutoxypropyl)-4,7-carbotartbutoxymethyl)-1,4,7-triazacyclononane ((R)-NODAGA(tBu)3), to obtain (R)-NODAGA-Phe-Phe-D-Lys(suberoyl)-Lys-urea-Glu (CC34). CC34 was labeled with 111In, 68Ga and 64Cu. The radioconjugates were further evaluated in vitro and in vivo in LNC…