{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,3]],"date-time":"2026-04-03T14:59:28Z","timestamp":1775228368814,"version":"3.50.1"},"reference-count":34,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2022,5,26]],"date-time":"2022-05-26T00:00:00Z","timestamp":1653523200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003827","name":"Hungarian National Research, Development and Innovation Office","doi-asserted-by":"publisher","award":["K-128201"],"award-info":[{"award-number":["K-128201"]}],"id":[{"id":"10.13039\/501100003827","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003827","name":"Hungarian National Research, Development and Innovation Office","doi-asserted-by":"publisher","award":["134694"],"award-info":[{"award-number":["134694"]}],"id":[{"id":"10.13039\/501100003827","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003827","name":"Hungarian National Research, Development and Innovation Office","doi-asserted-by":"publisher","award":["TKP2020-NKA-04"],"award-info":[{"award-number":["TKP2020-NKA-04"]}],"id":[{"id":"10.13039\/501100003827","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Thematic Excellence Programme of the Ministry for Innovation and Technology","award":["K-128201"],"award-info":[{"award-number":["K-128201"]}]},{"name":"Thematic Excellence Programme of the Ministry for Innovation and Technology","award":["134694"],"award-info":[{"award-number":["134694"]}]},{"name":"Thematic Excellence Programme of the Ministry for Innovation and Technology","award":["TKP2020-NKA-04"],"award-info":[{"award-number":["TKP2020-NKA-04"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pharmaceuticals"],"abstract":"<jats:p>Hypoxia promotes angiogenesis, which is crucial for tumor growth, and induces malignant progression and increases the therapeutic resistance. Positron emission tomography (PET) enables the detection of the hypoxic regions in tumors using 2-nitroimidazole-based radiopharmaceuticals. We describe here a physicochemical study of the Sc(DO3AM-NI) complex, which indicates: (a) relatively slow formation of the Sc(DO3AM-NI) chelate in acidic solution; (b) lower thermodynamic stability than the reference Sc(DOTA); (c) however, it is substantially more inert and consequently can be regarded as an excellent Sc-binder system. In addition, we report a comparison of 44Sc-labeled DO3AM-NI with its known 68Ga-labeled analog as a hypoxia PET probe. The in vivo and ex vivo biodistributions of 44Sc- and 68Ga-labeled DO3AM-NI in healthy and KB tumor-bearing SCID mice were examined 90 and 240 min after intravenous injection. No significant difference was found between the accumulation of 44Sc- and 68Ga-labeled DO3AM-NI in KB tumors. However, a significantly higher accumulation of [68Ga]Ga(DO3AM-NI) was found in liver, spleen, kidney, intestine, lung, heart and brain than for [44Sc]Sc(DO3AM-NI), leading to a lower tumor\/background ratio. The tumor-to-muscle (T\/M) ratio of [44Sc]Sc(DO3AM-NI) was approximately 10\u201315-fold higher than that of [68Ga]Ga(DO3AM-NI) at all time points. Thus, [44Sc]Sc(DO3AM-NI) allows the visualization of KB tumors with higher resolution, making it a promising hypoxia-specific PET radiotracer.<\/jats:p>","DOI":"10.3390\/ph15060666","type":"journal-article","created":{"date-parts":[[2022,5,29]],"date-time":"2022-05-29T23:43:03Z","timestamp":1653867783000},"page":"666","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Synthesis, Physicochemical, Labeling and In Vivo Characterization of 44Sc-Labeled DO3AM-NI as a Hypoxia-Sensitive PET Probe"],"prefix":"10.3390","volume":"15","author":[{"given":"D\u00e1niel","family":"Sz\u00fccs","sequence":"first","affiliation":[{"name":"Division of Nuclear Medicine and Translational Imaging, Department of Medical Imaging, Faculty of Medicine, University of Debrecen, Nagyerdei krt. 98., H-4032 Debrecen, Hungary"},{"name":"Department of Physical Chemistry, Faculty of Science and Technology, University of Debrecen, Egyetem t\u00e9r 1., H-4032 Debrecen, Hungary"},{"name":"Doctoral School of Chemistry, Faculty of Science and Technology, University of Debrecen, Egyetem t\u00e9r 1., H-4032 Debrecen, Hungary"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2345-6428","authenticated-orcid":false,"given":"Tibor","family":"Csup\u00e1sz","sequence":"additional","affiliation":[{"name":"Department of Physical Chemistry, Faculty of Science and Technology, University of Debrecen, Egyetem t\u00e9r 1., H-4032 Debrecen, Hungary"},{"name":"Doctoral School of Chemistry, Faculty of Science and Technology, University of Debrecen, Egyetem t\u00e9r 1., H-4032 Debrecen, Hungary"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Judit P.","family":"Szab\u00f3","sequence":"additional","affiliation":[{"name":"Division of Nuclear Medicine and Translational Imaging, Department of Medical Imaging, Faculty of Medicine, University of Debrecen, Nagyerdei krt. 98., H-4032 Debrecen, Hungary"},{"name":"Doctoral School of Clinical Medicine, Faculty of Medicine, University of Debrecen, Nagyerdei krt. 98., H-4032 Debrecen, Hungary"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Adrienn","family":"Kis","sequence":"additional","affiliation":[{"name":"Division of Nuclear Medicine and Translational Imaging, Department of Medical Imaging, Faculty of Medicine, University of Debrecen, Nagyerdei krt. 98., H-4032 Debrecen, Hungary"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7297-5489","authenticated-orcid":false,"given":"Barbara","family":"Gyuricza","sequence":"additional","affiliation":[{"name":"Division of Nuclear Medicine and Translational Imaging, Department of Medical Imaging, Faculty of Medicine, University of Debrecen, Nagyerdei krt. 98., H-4032 Debrecen, Hungary"},{"name":"Doctoral School of Chemistry, Faculty of Science and Technology, University of Debrecen, Egyetem t\u00e9r 1., H-4032 Debrecen, Hungary"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Vikt\u00f3ria","family":"Arat\u00f3","sequence":"additional","affiliation":[{"name":"Division of Nuclear Medicine and Translational Imaging, Department of Medical Imaging, Faculty of Medicine, University of Debrecen, Nagyerdei krt. 98., H-4032 Debrecen, Hungary"},{"name":"Doctoral School of Pharmaceutical Sciences, Faculty of Pharmacy, University of Debrecen, Nagyerdei krt. 98., H-4032 Debrecen, Hungary"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8586-3942","authenticated-orcid":false,"given":"Vikt\u00f3ria","family":"Forg\u00e1cs","sequence":"additional","affiliation":[{"name":"Division of Nuclear Medicine and Translational Imaging, Department of Medical Imaging, Faculty of Medicine, University of Debrecen, Nagyerdei krt. 98., H-4032 Debrecen, Hungary"},{"name":"Doctoral School of Chemistry, Faculty of Science and Technology, University of Debrecen, Egyetem t\u00e9r 1., H-4032 Debrecen, Hungary"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Adrienn","family":"V\u00e1gner","sequence":"additional","affiliation":[{"name":"Scanomed Ltd., Nagyerdei krt. 98., H-4032 Debrecen, Hungary"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"G\u00e1bor","family":"Nagy","sequence":"additional","affiliation":[{"name":"Scanomed Ltd., Nagyerdei krt. 98., H-4032 Debrecen, Hungary"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ildik\u00f3","family":"Garai","sequence":"additional","affiliation":[{"name":"Division of Nuclear Medicine and Translational Imaging, Department of Medical Imaging, Faculty of Medicine, University of Debrecen, Nagyerdei krt. 98., H-4032 Debrecen, Hungary"},{"name":"Scanomed Ltd., Nagyerdei krt. 98., H-4032 Debrecen, Hungary"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dezs\u0151","family":"Szikra","sequence":"additional","affiliation":[{"name":"Division of Nuclear Medicine and Translational Imaging, Department of Medical Imaging, Faculty of Medicine, University of Debrecen, Nagyerdei krt. 98., H-4032 Debrecen, Hungary"},{"name":"Scanomed Ltd., Nagyerdei krt. 98., H-4032 Debrecen, Hungary"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Imre","family":"T\u00f3th","sequence":"additional","affiliation":[{"name":"Department of Physical Chemistry, Faculty of Science and Technology, University of Debrecen, Egyetem t\u00e9r 1., H-4032 Debrecen, Hungary"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6456-6212","authenticated-orcid":false,"given":"Gy\u00f6rgy","family":"Trencs\u00e9nyi","sequence":"additional","affiliation":[{"name":"Division of Nuclear Medicine and Translational Imaging, Department of Medical Imaging, Faculty of Medicine, University of Debrecen, Nagyerdei krt. 98., H-4032 Debrecen, Hungary"},{"name":"Scanomed Ltd., Nagyerdei krt. 98., H-4032 Debrecen, 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