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Synthesis of 99mTc-labeled 2-Mercaptobenzimidazole as a novel radiotracer to diagnose tumor hypoxia.

ABSTRACT: Discovery of 99mTc-labeled imidazole derivatives as a potential radiotracer for hypoxic tumor imaging is considered to be of great interest because of non-invasive detection capabilities. 2-Mercaptobenzimidazole (2-MBI) was successfully synthesized, characterized and radiolabeled with [99mTc (CO)3(H2O)3]+ intermediate to form 99mTc-2-MBI complex with radiochemical purity of ?95% yield as observed by instant-thin layer chromatography (ITLC) and radio-high performance liquid chromatography (radio-HPLC). The 99mTc-2-MBI complex was observed to be stable in saline and serum with no noticeable decomposition at room temperature and 37?°C, respectively, over a time period of 24?h. Biodistribution results in Balb/c mice bearing S180 tumor show that 99mTc-2-MBI highly internalized in tumor tissue, also possess preferably high tumor/muscle and tumor/blood ratios 4.14?±?0.77 and 3.91?±?0.63, respectively at 24?h incubation. Scintigraphic imaging study shows 99mTc-2-MBI is visibly accumulated in hypoxic tumor tissue, suggesting it would be a promising radiotracer for early stage diagnosis of tumor hypoxia.

SUBMITTER: Rizvi SFA

PROVIDER: S-EPMC7475274 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

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Synthesis of 99mTc-labeled 2-Mercaptobenzimidazole as a novel radiotracer to diagnose tumor hypoxia.

Rizvi Syed Faheem Askari SFA Zhang Haixia H Mehmood Sajid S Sanad Mahmoud M

Translational oncology 20200828 12

Discovery of 99mTc-labeled imidazole derivatives as a potential radiotracer for hypoxic tumor imaging is considered to be of great interest because of non-invasive detection capabilities. 2-Mercaptobenzimidazole (2-MBI) was successfully synthesized, characterized and radiolabeled with [99mTc (CO)3(H2O)3]+ intermediate to form 99mTc-2-MBI complex with radiochemical purity of ≥95% yield as observed by instant-thin layer c ...[more]

PMID: 32862104

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Synthesis of 99mTc-labeled 2-Mercaptobenzimidazole as a novel radiotracer to diagnose tumor hypoxia.

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Synthesis of <sup>99m</sup>Tc-labeled 2-Mercaptobenzimidazole as a novel radiotracer to diagnose tumor hypoxia.

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