Liu M.Zheng Y.Avcibasi U.Liu S.2024-07-222024-07-22201609698051http://akademikarsiv.cbu.edu.tr:4000/handle/123456789/15715Introduction In this study, novel 99mTc(III)-azide complexes [99mTc(N3)(CDO)(CDOH)2B-R] (99mTc-ISboroxime-N3: R = IS; 99mTc-MPboroxime-N3: R = MP; 99mTc-PAboroxime-N3: R = PA; 99mTc-PYboroxime-N3: R = PY; and 99mTc-Uboroxime-N3: R = 5U) were evaluated as heart imaging agents. Methods Complexes [99mTc(N3)(CDO)(CDOH)2B-R] (R = IS, MP, PA, PY and 5U) were prepared by ligand exchange between NaN3 and [99mTcCl(CDO)(CDOH)2B-R]. Biodistribution and imaging studies were carried out in Sprague–Dawley rats. Image quantification was performed to compare their initial heart uptake and myocardial retention. Results 99mTc-ISboroxime-N3, 99mTc-PYboroxime-N3 and 99mTc-Uboroxime-N3 were prepared with high RCP (93–98%) while the RCP of 99mTc-MPboroxime-N3 and 99mTc-PAboroxime-N3 was 80–85%. The myocardial retention curves of 99mTc-ISboroxime-N3, 99mTc-PYboroxime-N3 and 99mTc-Uboroxime-N3 were best fitted to the bi-exponential decay function. The half-time of the fast component was 1.6 ± 0.4 min for 99mTc-ISboroxime-N3, 0.7 ± 0.1 min for 99mTc-PYboroxime-N3 and 0.9 ± 0.4 min for 99mTc-Uboroxime-N3. The 2-min heart uptake from biodistribution studies followed the ranking order of 99mTc-ISboroxime-N3 (3.60 ± 0.68%ID/g) > 99mTc-PYboroxime-N3 (2.35 ± 0.37%ID/g) ≫ 99mTc-Uboroxime-N3 (1.29 ± 0.06%ID/g). 99mTc-ISboroxime-N3 had the highest 2-min heart uptake among 99mTc radiotracers revaluated in SD rats. High quality SPECT images were obtained with the right and left ventricular walls being clearly delineated. The best image acquisition window was 0–5 min for 99mTc-ISboroxime-N3. Conclusion Both azide coligand and boronate caps had significant impact on the heart uptake and myocardial retention of complexes [99mTc(N3)(CDO)(CDOH)2B-R]. Among the radiotracers evaluated in SD rats, 99mTc-ISboroxime-N3 has the highest initial heart uptake with the heart retention comparable to that of 99mTc-Teboroxime. 99mTc-ISboroxime-N3 is a promising alternative to 99mTc-Teboroxime for SPECT MPI. © 2016 Elsevier Inc.EnglishAll Open Access; Green Open AccessAnimalsHeartImage Processing, Computer-AssistedMyocardiumOrganotechnetium CompoundsOximesRadioactive TracersRadiochemistryRatsRats, Sprague-DawleyTissue DistributionTomography, Emission-Computed, Single-Photon99mTc 1h pyrazol 3 ylboronic acid boroxime99mTc 1h pyrazol 3 ylboronic acid boroxime n399mTc 3 pyridineboronic acid boroxime99mTc 3 pyridineboronic acid boroxime n399mTc isoxazole 4 boronic acid boroxime99mTc isoxazole 4 boronic acid boroxime n399mTc n methylpyridinium 4 boronic acid iodide boroxime99mTc n methylpyridinium 4 boronic acid iodide boroxime n399mTc teboroxime99mTc teboroxime n399mTc trioxime99mTc trioxime n399mTc uracil 5 boronic acid boroxime99mTc uracil 5 boronic acid boroxime n3tracerunclassified drugoximetechnetium complextraceranimal experimentArticlecardiac imagingcontrolled studydynamic planar imagingheart left ventricle wallheart right ventricleimage reconstructionnonhumannuclear magnetic resonance imagingradiochemistryratright ventricular wallsingle photon emission computer tomographySprague Dawley ratanimalcardiac musclechemistrydiagnostic imagingheartimage processingmetabolismproceduressingle photon emission computed tomographytissue distributionArticle10.1016/j.nucmedbio.2016.05.001