1
|
Radiochemistry with {Al18F}2+: Current status and optimization perspectives for efficient radiofluorination by complexation. Coord Chem Rev 2023. [DOI: 10.1016/j.ccr.2023.215028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
|
2
|
Chen L, Gao Y, Ge J, Zhou Y, Yang Z, Li C, Huang B, Lu K, Kou D, Zhou D, Chen C, Wang S, Wu S, Zeng J, Huang G, Gao M. A clinically translatable kit for MRI/NMI dual-modality nanoprobes based on anchoring group-mediated radiolabeling. NANOSCALE 2023; 15:3991-3999. [PMID: 36723217 DOI: 10.1039/d2nr05988f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Magnetic resonance imaging (MRI)/nuclear medicine imaging (NMI) dual-modality imaging based on radiolabeled nanoparticles has been increasingly exploited for accurate diagnosis of tumor and cardiovascular diseases by virtue of high spatial resolution and high sensitivity. However, significant challenges exist in pursuing truly clinical applications, including massive preparation and rapid radiolabeling of nanoparticles. Herein, we report a clinically translatable kit for the convenient construction of MRI/NMI nanoprobes relying on the flow-synthesis and anchoring group-mediated radiolabeling (LAGMERAL) of iron oxide nanoparticles. First, homogeneous iron oxide nanoparticles with excellent performance were successfully obtained on a large scale by flow synthesis, followed by the surface anchoring of diphosphonate-polyethylene glycol (DP-PEG) to simultaneously render the underlying nanoparticles biocompatible and competent in robust labeling of radioactive metal ions. Moreover, to enable convenient and safe usage in clinics, the DP-PEG modified nanoparticle solution was freeze-dried and sterilized to make a radiolabeling kit followed by careful evaluations of its in vitro and in vivo performance and applicability. The results showed that 99mTc labeled nanoprobes are effectively obtained with a labeling yield of over 95% in 30 minutes after simply injecting Na[99mTcO4] solution into the kit. In addition, the Fe3O4 nanoparticles sealed in the kit can well stand long-term storage even for 300 days without deteriorating the colloidal stability and radiolabeling yield. Upon intravenous injection of the as-prepared radiolabeled nanoprobes, high-resolution vascular images of mice were obtained by vascular SPECT imaging and magnetic resonance angiography, demonstrating the promising clinical translational value of our radiolabeling kit.
Collapse
Affiliation(s)
- Lei Chen
- Center for Molecular Imaging and Nuclear Medicine, State Key Laboratory of Radiation Medicine and Protection, School for Radiological and Interdisciplinary Sciences (RAD-X), Soochow University, Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, Suzhou 215123, China.
| | - Yun Gao
- Center for Molecular Imaging and Nuclear Medicine, State Key Laboratory of Radiation Medicine and Protection, School for Radiological and Interdisciplinary Sciences (RAD-X), Soochow University, Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, Suzhou 215123, China.
| | - Jianxian Ge
- Center for Molecular Imaging and Nuclear Medicine, State Key Laboratory of Radiation Medicine and Protection, School for Radiological and Interdisciplinary Sciences (RAD-X), Soochow University, Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, Suzhou 215123, China.
| | - Yi Zhou
- Center for Molecular Imaging and Nuclear Medicine, State Key Laboratory of Radiation Medicine and Protection, School for Radiological and Interdisciplinary Sciences (RAD-X), Soochow University, Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, Suzhou 215123, China.
| | - Zhe Yang
- Center for Molecular Imaging and Nuclear Medicine, State Key Laboratory of Radiation Medicine and Protection, School for Radiological and Interdisciplinary Sciences (RAD-X), Soochow University, Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, Suzhou 215123, China.
| | - Cang Li
- Center for Molecular Imaging and Nuclear Medicine, State Key Laboratory of Radiation Medicine and Protection, School for Radiological and Interdisciplinary Sciences (RAD-X), Soochow University, Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, Suzhou 215123, China.
| | - Baoxing Huang
- Center for Molecular Imaging and Nuclear Medicine, State Key Laboratory of Radiation Medicine and Protection, School for Radiological and Interdisciplinary Sciences (RAD-X), Soochow University, Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, Suzhou 215123, China.
| | - Kuan Lu
- Center for Molecular Imaging and Nuclear Medicine, State Key Laboratory of Radiation Medicine and Protection, School for Radiological and Interdisciplinary Sciences (RAD-X), Soochow University, Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, Suzhou 215123, China.
| | - Dandan Kou
- Center for Molecular Imaging and Nuclear Medicine, State Key Laboratory of Radiation Medicine and Protection, School for Radiological and Interdisciplinary Sciences (RAD-X), Soochow University, Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, Suzhou 215123, China.
| | - Dandan Zhou
- Center for Molecular Imaging and Nuclear Medicine, State Key Laboratory of Radiation Medicine and Protection, School for Radiological and Interdisciplinary Sciences (RAD-X), Soochow University, Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, Suzhou 215123, China.
| | - Can Chen
- Center for Molecular Imaging and Nuclear Medicine, State Key Laboratory of Radiation Medicine and Protection, School for Radiological and Interdisciplinary Sciences (RAD-X), Soochow University, Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, Suzhou 215123, China.
| | - Sixia Wang
- Center for Molecular Imaging and Nuclear Medicine, State Key Laboratory of Radiation Medicine and Protection, School for Radiological and Interdisciplinary Sciences (RAD-X), Soochow University, Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, Suzhou 215123, China.
| | - Shuwang Wu
- Center for Molecular Imaging and Nuclear Medicine, State Key Laboratory of Radiation Medicine and Protection, School for Radiological and Interdisciplinary Sciences (RAD-X), Soochow University, Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, Suzhou 215123, China.
| | - Jianfeng Zeng
- Center for Molecular Imaging and Nuclear Medicine, State Key Laboratory of Radiation Medicine and Protection, School for Radiological and Interdisciplinary Sciences (RAD-X), Soochow University, Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, Suzhou 215123, China.
| | - Gang Huang
- Shanghai Key Laboratory of Molecular Imaging, Shanghai University of Medicine and Health Sciences, Shanghai 201318, China
| | - Mingyuan Gao
- Center for Molecular Imaging and Nuclear Medicine, State Key Laboratory of Radiation Medicine and Protection, School for Radiological and Interdisciplinary Sciences (RAD-X), Soochow University, Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, Suzhou 215123, China.
- Shanghai Key Laboratory of Molecular Imaging, Shanghai University of Medicine and Health Sciences, Shanghai 201318, China
- The Second Affiliated Hospital of Soochow University, Suzhou 215004, China
| |
Collapse
|
3
|
Lepareur N. Cold Kit Labeling: The Future of 68Ga Radiopharmaceuticals? Front Med (Lausanne) 2022; 9:812050. [PMID: 35223907 PMCID: PMC8869247 DOI: 10.3389/fmed.2022.812050] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 01/07/2022] [Indexed: 12/11/2022] Open
Abstract
Over the last couple of decades, gallium-68 (68Ga) has gained a formidable interest for PET molecular imaging of various conditions, from cancer to infection, through cardiac pathologies or neuropathies. It has gained routine use, with successful radiopharmaceuticals such as somatostatin analogs ([68Ga]Ga-DOTATOC and [68Ga]GaDOTATATE) for neuroendocrine tumors, and PSMA ligands for prostate cancer. It represents a major clinical impact, particularly in the context of theranostics, coupled with their 177Lu-labeled counterparts. Beside those, a bunch of new 68Ga-labeled molecules are in the preclinical and clinical pipelines, with some of them showing great promise for patient care. Increasing clinical demand and regulatory issues have led to the development of automated procedures for the production of 68Ga radiopharmaceuticals. However, the widespread use of these radiopharmaceuticals may rely on simple and efficient radiolabeling methods, undemanding in terms of equipment and infrastructure. To make them technically and economically accessible to the medical community and its patients, it appears mandatory to develop a procedure similar to the well-established kit-based 99mTc chemistry. Already available commercial kits for the production of 68Ga radiopharmaceuticals have demonstrated the feasibility of using such an approach, thus paving the way for more kit-based 68Ga radiopharmaceuticals to be developed. This article discusses the development of 68Ga cold kit radiopharmacy, including technical issues, and regulatory aspects.
Collapse
Affiliation(s)
- Nicolas Lepareur
- Comprehensive Cancer Center Eugène Marquis, Rennes, France
- Univ Rennes, Inrae, Inserm, Institut NUMECAN (Nutrition, Métabolismes et Cancer), UMR_A 1341, UMR_S 1241, Rennes, France
| |
Collapse
|
4
|
Suthiram J, Ebenhan T, Marjanovic-Painter B, Sathekge MM, Zeevaart JR. Towards Facile Radiolabeling and Preparation of Gallium-68-/Bismuth-213-DOTA-[Thi 8, Met(O 2) 11]-Substance P for Future Clinical Application: First Experiences. Pharmaceutics 2021; 13:pharmaceutics13091326. [PMID: 34575402 PMCID: PMC8472077 DOI: 10.3390/pharmaceutics13091326] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Revised: 08/08/2021] [Accepted: 08/11/2021] [Indexed: 11/16/2022] Open
Abstract
Substance P (SP) is a small peptide commonly known as a preferential endogenous ligand for the transmembrane neurokinin-1 receptor. Nuclear Medicine procedures currently involve radiolabeled SP derivatives in peptide radioligand endotherapy of inoperable glioblastoma. Promising clinical results sparked the demand for facile production strategies for a functionalized 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid-[Thi8, Met(O2)11]-SP to allow for rapid Gallium-68 or Bismuth-213 complexation. Therefore, we provide a simple kit-like radiotracer preparation method that caters for the gallium-68 activity eluted from a SnO2 generator matrix as well as preliminary results on the adaptability to produce [213Bi]Bi-DOTA-[Thi8, Met(O2)11]SP from the same vials containing the same starting material. Following a phase of radioanalysis for complexation of gallium-68 to DOTA-[Thi8, Met(O2)11]SP and assessing the radiolabeling parameters, the vials containing appropriate kit-prototype material were produced in freeze-dried batches. The facile radiolabeling performance was tested and parameters for future human application were calculated to meet the criteria for theranostic loco-regional co-administration of activity doses comprising [68Ga]Ga-DOTA-[Thi8, Met(O2)11]SP mixed with [213Bi]Bi-DOTA-[Thi8, Met(O2)11]SP. [68Ga]Ga-DOTA-[Thi8, Met(O2)11]SP was prepared quantitatively from lyophilized starting material within 25 min providing the required molar activity (18 ± 4 GBq/µmol) and activity concentration (98 ± 24 MBq/mL), radiochemical purity (>95%) and sustained radiolabeling performance (4 months at >95% LE) as well as acceptable product quality (>95% for 120 min). Additionally, vials of the same starting materials were successfully adapted to a labeling strategy available for preparation of [213Bi]Bi-DOTA-[Thi8, Met(O2)11]SP providing sufficient activity for 1-2 human doses. The resultant formulation of [68Ga]Ga-/[213Bi]Bi-DOTA-[Thi8, Met(O2)11]SP activity doses was considered of adequate radiochemical quality for administration. This investigation proposes a simple kit-like formulation of DOTA-[Thi8, Met(O2)11]SP-a first-line investigation into a user friendly, straightforward tracer preparation that would warrant efficient clinical investigations in the future. Quantitative radiolabeling was accomplished for [68Ga]Ga-DOTA-[Thi8, Met(O2)11]SP and [213Bi]Bi-DOTA-[Thi8, Met(O2)11]SP preparations; a key requirement when addressing the specific route of catheter-assisted co-injection directly into the intratumoral cavities.
Collapse
Key Words
- 68Ge/68Ga generator
- DOTA
- DOTA-Substance P
- [213Bi]Bi-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid-[Thi8, Met(O2)11]-Substance-P
- [68Ga]Ga-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid-[Thi8, Met(O2)11]-Substance-P
- gallium-68
- kit preparation
Collapse
Affiliation(s)
- Janine Suthiram
- Radiochemistry, The South African Nuclear Energy Corporation (Necsa), Brits 0240, South Africa; (J.S.); (T.E.); (B.M.-P.)
- Department of Nuclear Medicine, University of Pretoria, Pretoria 0001, South Africa;
| | - Thomas Ebenhan
- Radiochemistry, The South African Nuclear Energy Corporation (Necsa), Brits 0240, South Africa; (J.S.); (T.E.); (B.M.-P.)
- Department of Nuclear Medicine, University of Pretoria, Pretoria 0001, South Africa;
- Nuclear Medicine Research Infrastructure (NuMeRI), Steve Biko Academic Hospital, Pretoria 0001, South Africa
| | - Biljana Marjanovic-Painter
- Radiochemistry, The South African Nuclear Energy Corporation (Necsa), Brits 0240, South Africa; (J.S.); (T.E.); (B.M.-P.)
| | - Mike M. Sathekge
- Department of Nuclear Medicine, University of Pretoria, Pretoria 0001, South Africa;
- Nuclear Medicine Research Infrastructure (NuMeRI), Steve Biko Academic Hospital, Pretoria 0001, South Africa
- Department of Nuclear Medicine, Steve Biko Academic Hospital, University of Pretoria, Pretoria 0001, South Africa
| | - Jan Rijn Zeevaart
- Radiochemistry, The South African Nuclear Energy Corporation (Necsa), Brits 0240, South Africa; (J.S.); (T.E.); (B.M.-P.)
- Nuclear Medicine Research Infrastructure (NuMeRI), Steve Biko Academic Hospital, Pretoria 0001, South Africa
- Preclinical Drug Development Platform, Department of Science and Technology, North West University, Potchefstroom 2520, South Africa
- Correspondence: ; Tel.: +27-12-305-5786
| |
Collapse
|
5
|
Kleynhans J, Rubow S, le Roux J, Marjanovic-Painter B, Zeevaart JR, Ebenhan T. Production of [ 68 Ga]Ga-PSMA: Comparing a manual kit-based method with a module-based automated synthesis approach. J Labelled Comp Radiopharm 2020; 63:553-563. [PMID: 32865290 DOI: 10.1002/jlcr.3879] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 08/03/2020] [Accepted: 08/26/2020] [Indexed: 12/14/2022]
Abstract
The labeling of peptides with gallium-68 is often initially performed by manual labeling, but with high clinical demand, other alternatives are needed. Cold-kits or automated synthesis are viable options for standardized methods and deemed pharmaceutically more acceptable. This study compares these [68 Ga]Ga-PSMA-11 production methods. Data from 40 kit-based and 40 automated syntheses of [68 Ga]Ga-PSMA-11 were analyzed. Pre-set criteria were evaluated including radiochemical purity, radionuclidic purity, chemical purity, physiological acceptability and sterility. The operator time and radiation dose received were measured. The robustness and repeatability of each method were assessed and a comparison of the running costs of each method is also provided. For both the methods all the analyzed products met the release criteria. No differences were found in radiochemical purity, radiochemical identity, radionuclidic purity, and sterility. However, radiochemical yield and apparent molar activity showed significant differences. For both methods, whole body radiation exposure to operators was lower than with manual labeling (25 - 40 μSv). The exposure during kit-based labeling (14.5 ± μSv) was seven times higher than that of automated synthesis (2.05 ± 0.99 μSv). The automated synthesis was the more expensive method. Both methods are sound alternatives to manual synthesis and offer higher quality, better radiation protection and a more reliable manufacturing of radiopharmaceuticals.
Collapse
Affiliation(s)
- Janke Kleynhans
- Nuclear Medicine Division, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
- NuMeRI, Nuclear Medicine Research Infrastructure NPC, Pretoria, South Africa
| | - Sietske Rubow
- Nuclear Medicine Division, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Jannie le Roux
- Nuclear Medicine Division, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
- NuMeRI Node for Infection Imaging, Central Analytical Facilities, Stellenbosch University, Stellenbosch, South Africa
| | | | - Jan Rijn Zeevaart
- NuMeRI, Nuclear Medicine Research Infrastructure NPC, Pretoria, South Africa
- The South African Nuclear Energy Corporation (Necsa), Radiochemistry, Pelindaba, Brits, South Africa
| | - Thomas Ebenhan
- NuMeRI, Nuclear Medicine Research Infrastructure NPC, Pretoria, South Africa
- The South African Nuclear Energy Corporation (Necsa), Radiochemistry, Pelindaba, Brits, South Africa
- Nuclear Medicine, University of Pretoria, Pretoria, South Africa
| |
Collapse
|
6
|
Prince D, Rossouw D, Rubow S. Optimization of a Labeling and Kit Preparation Method for Ga-68 Labeled DOTATATE, Using Cation Exchange Resin Purified Ga-68 Eluates Obtained from a Tin Dioxide 68Ge/68Ga Generator. Mol Imaging Biol 2018; 20:1008-1014. [DOI: 10.1007/s11307-018-1195-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
|
7
|
Pandey U, Korde A, Mukherjee A, Shinto A, Kamaleswaran KK, Jose RP, Gamre N, Dash A. Clinical experience with indigenous kit-based preparation of 68Ga-DOTATOC using commercial 68Ge/ 68Ga generator. Appl Radiat Isot 2018; 136:59-64. [PMID: 29471222 DOI: 10.1016/j.apradiso.2018.02.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Revised: 01/15/2018] [Accepted: 02/01/2018] [Indexed: 12/19/2022]
Abstract
Pharmaceutical grade DOTATOC kits compliant with all the quality control criteria were formulated and radiolabeled with 68Ga in high yields. Comparison with module-based 68Ga-DOTATOC established product equivalency. Clinical utility was evaluated in patients with histopathologically confirmed well-differentiated neuroendocrine tumors. Kit-based preparation of 68Ga-DOTATOC could identify sites of primary and metastatic disease. PET/CT images of patients conformed to the established criteria for somatostatin imaging agents and clinical expectations. Results of this study emphasize the potential of kit-based 68Ga-DOTATOC for PET imaging of neuroendocrine tumors.
Collapse
Affiliation(s)
- Usha Pandey
- Radiopharmaceuticals Division, Bhabha Atomic Research Centre (BARC), Mumbai 400085, India; Homi Bhabha National Institute, Anushakti Nagar, Mumbai 400094, India
| | - Aruna Korde
- Radiopharmaceuticals Division, Bhabha Atomic Research Centre (BARC), Mumbai 400085, India; Homi Bhabha National Institute, Anushakti Nagar, Mumbai 400094, India.
| | - Archana Mukherjee
- Radiopharmaceuticals Division, Bhabha Atomic Research Centre (BARC), Mumbai 400085, India; Homi Bhabha National Institute, Anushakti Nagar, Mumbai 400094, India
| | - Ajit Shinto
- Department of Nuclear Medicine and PET/CT, Kovai Medical Centre & Hospital Limited, Coimbatore, Tamil Nadu, India
| | - K K Kamaleswaran
- Department of Nuclear Medicine and PET/CT, Kovai Medical Centre & Hospital Limited, Coimbatore, Tamil Nadu, India
| | - Raghi P Jose
- Department of Nuclear Medicine and PET/CT, Kovai Medical Centre & Hospital Limited, Coimbatore, Tamil Nadu, India
| | - Naresh Gamre
- Radiopharmaceuticals Division, Bhabha Atomic Research Centre (BARC), Mumbai 400085, India
| | - Ashutosh Dash
- Radiopharmaceuticals Division, Bhabha Atomic Research Centre (BARC), Mumbai 400085, India; Homi Bhabha National Institute, Anushakti Nagar, Mumbai 400094, India
| |
Collapse
|
8
|
Development and Evaluation of User-Friendly Single Vial DOTA-Peptide Kit Formulations, Specifically Designed for Radiolabelling with 68Ga from a Tin Dioxide 68Ge/68Ga Generator. Mol Imaging Biol 2017; 19:817-824. [DOI: 10.1007/s11307-017-1077-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
9
|
Seemann J, Waldron B, Parker D, Roesch F. DATATOC: a novel conjugate for kit-type 68Ga labelling of TOC at ambient temperature. EJNMMI Radiopharm Chem 2016; 1:4. [PMID: 29564381 PMCID: PMC5843802 DOI: 10.1186/s41181-016-0007-3] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Accepted: 02/12/2016] [Indexed: 11/10/2022] Open
Abstract
Background The widespread acceptance and application of 68Ga-PET depends on our ability to develop radiopharmaceuticals that can be prepared in a convenient and suitable manner. A kit-type labelling protocol provides such characteristics and requires chelators that can be radiolabelled under exceptionally mild conditions. Recently the DATA chelators have been introduced that fulfil these requirements. In continuing their development, the synthesis and radiolabelling of the first DATA bifunctional chelator (BFC) and peptide conjugate are described. Results A BFC derived from the DATA ligand (2,2'-(6-((carboxymethyl)amino)-1,4-diazepane-1,4-diyl)diacetic acid) has been synthesised in five steps from simple building blocks, with an overall yield of 8 %. DATAM5-3tBu (5-[1,4-Bis-tert-butoxycarbonylmethyl-6-(tert-butoxycarbonylmethyl-methyl-amino)-[1, 4]diazepan-6-yl]-pentanoic acid) has been coupled to [DPhe1][Tyr3]-octreotide (TOC) and the resulting peptide conjugate (DATATOC) radiolabelled with purified 68Ga derived via four different 68Ge/68Ga generator post-processing (PP) methods. The stability and lipophilicity of the radiotracer have been assessed and a kit-type formulation for radiolabelling evaluated. 68Ga-DATATOC has been prepared with a > 95 % radiochemical yield (RCY) within 1 (fractionated and acetone-PP) and 10 min (ethanol- and NaCl-PP) at 23 °C (pH 4.2-4.9, 13 nmol). The radiolabelled peptide is stable in the presence of human serum. Lipophilicity of 68Ga-DATATOC was calculated as logP = -3.2 ± 0.3, with a HPLC retention time (tR = 10.4 min) similar to 68Ga-DOTATOC (logP = -2.9 ± 0.4, tR = 10.3 min). Kit-type labelling from a lyophilised solid using acetone-PP based labelling achieves > 95 % RCY in 10 min at 23 °C. Conclusions The favourable labelling properties of the DATA chelators have been retained for DATATOC. High radiochemical purity can be achieved at 23 °C in less than 1 min and from a kit formulation. The speed, reliability, ease, flexibility and simplicity with which 68Ga-DATATOC can be prepared makes it a very attractive alternative to current standards.
Collapse
Affiliation(s)
- Johanna Seemann
- Institute of Nuclear Chemistry, Johannes Gutenberg University, Fritz-Strassmann-Weg 2, 55128 Mainz, Germany
| | - Bradley Waldron
- Institute of Nuclear Chemistry, Johannes Gutenberg University, Fritz-Strassmann-Weg 2, 55128 Mainz, Germany
| | - David Parker
- Department of Chemistry, Durham University, South Road, Durham, DH1 3LE UK
| | - Frank Roesch
- Institute of Nuclear Chemistry, Johannes Gutenberg University, Fritz-Strassmann-Weg 2, 55128 Mainz, Germany
| |
Collapse
|
10
|
Seemann J, Waldron BP, Roesch F, Parker D. Approaching 'Kit-Type' Labelling with (68)Ga: The DATA Chelators. ChemMedChem 2015; 10:1019-26. [PMID: 25899500 DOI: 10.1002/cmdc.201500092] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2015] [Indexed: 12/26/2022]
Abstract
The DATA chelators are a novel class of tri-anionic ligands based on 6-amino-1,4-diazepine-triacetic acid, which have been introduced recently for the chelation of (68)Ga. Compared with macrocyclic chelators based on the cyclen scaffold (i.e., DOTA, DO3A, and DO2A derivatives), DATA chelators undergo quantitative radiolabelling more rapidly and under milder conditions. In this study, a systematic evaluation of the labelling of four DATA chelators--DATA(M), DATA(P), DATA(Ph), and DATA(PPh)--with (68)Ga is presented. The results highlight the extraordinary potential of this new class of chelators for application in molecular imaging using (68)Ga positron emission tomography (PET).
Collapse
Affiliation(s)
- Johanna Seemann
- Institute of Nuclear Chemistry, Johannes Gutenberg University, Fritz-Strassmann-Weg 2, 55128 Mainz (Germany).
| | - Bradley P Waldron
- Institute of Nuclear Chemistry, Johannes Gutenberg University, Fritz-Strassmann-Weg 2, 55128 Mainz (Germany).,Department of Chemistry, Durham University, South Road, Durham, DH1 3LE (UK)
| | - Frank Roesch
- Institute of Nuclear Chemistry, Johannes Gutenberg University, Fritz-Strassmann-Weg 2, 55128 Mainz (Germany)
| | - David Parker
- Department of Chemistry, Durham University, South Road, Durham, DH1 3LE (UK)
| |
Collapse
|