Swidan M.M.Khowessah O.M.El-Motaleb M.A.El-Bary A.A.El-Kolaly M.T.Sakr T.M.Labeled Compounds DepartmentHot Labs CenterEgyptian Atomic Energy AuthorityPO13759CairoEgypt; Pharmaceutics and Industrial Pharmacy DepartmentFaculty of PharmacyCairo UniversityPO11562CairoEgypt; Radioactive Isotopes and Generator DepartmentHot Labs CenterEgyptian Atomic Energy AuthorityPO13759CairoEgypt; Pharmaceutical Chemistry DepartmentFaculty of PharmacyModern Sciences and Arts University6th October CityEgypt2020-01-092020-01-09201915608115https://doi.org/10.1007/s40199-019-00241-yPubMed ID 30706223https://t.ly/py7mOScopusMSA Google ScholarBackground: The evolution of nanoparticles has gained prominence as platforms for developing diagnostic and/or therapeutic radiotracers. This study aims to develop a novel technique for fabricating a tumor diagnostic probe based on iron oxide nanoparticles excluding the utilization of chelating ligands. Methods: Tc-99m radionuclide was loaded into magnetic iron oxide nanoparticles platform (MIONPs) by sonication. 99mTc-encapsulated MIONPs were fully characterized concerning particles size, charge, radiochemical purity, encapsulation efficiency, in-vitro stability and cytotoxicity. These merits were biologically evaluated in normal and solid tumor bearing mice via different delivery approaches. Results: 99mTc-encapsulated MIONPs probe was synthesized with average particle size 24.08 7.9nm, hydrodynamic size 52nm, zeta potential -28mV, radiolabeling yield 96 0.83%, high in-vitro physiological stability, and appropriate cytotoxicity behavior. The in-vivo evaluation in solid tumor bearing mice revealed that the maximum tumor radioactivity accumulation (25.39 0.57, 36.40 0.59 and 72.61 0.82%ID/g) was accomplished at 60, 60 and 30min p.i. for intravenous, intravenous with physical magnet targeting and intratumoral delivery, respectively. The optimum T/NT ratios of 57.70, 65.00 and 87.48 were demonstrated at 60min post I.V., I.V. with physical magnet targeting and I.T. delivery, respectively. These chemical and biological characteristics of our prepared nano-probe demonstrate highly advanced merits over the previously reported chelator mediated radiolabeled nano-formulations which reported maximum tumor uptakes in the scope of 3.65 0.19 to 16.21 2.56%ID/g. Conclusion: Stabilized encapsulation of 99mTc radionuclide into MIONPs elucidates a novel strategy for developing an advanced nano-sized radiopharmaceutical for tumor diagnosis. [Figure not available: see fulltext.]. 2019, Springer Nature Switzerland AG.EnglishOctober University for Modern Sciences and Artsجامعة أكتوبر للعلوم الحديثة والآدابUniversity of Modern Sciences and ArtsMSA UniversityChelator free radiolabelingEncapsulationMagnetic iron oxide nanoparticlesTc-99m radionuclideTumor deliveryTumor diagnosismagnetic iron oxide nanoparticlemagnetic nanoparticletechnetium 99multrasmall superparamagnetic iron oxideunclassified drugferric ionferric oxidemagnetite nanoparticletechnetiumTechnetium-99animal experimentanimal modelanimal tissueArticlecell viabilitychemical parameterscontrolled studydrug cytotoxicitydrug delivery systemdrug stabilityencapsulation efficiencyhumanhuman cellhydrodynamic sizein vitro studyin vivo studyisotope labelingmolecular imagingmousenanoencapsulationnonhumanparticle chargeparticle sizephysical parametersradiochemical puritysynthesistumor diagnosisultrasoundzeta potentialanimalcancer transplantationcell linecell survivalchemistrydiagnostic imagingintravenous drug administrationAdministration, IntravenousAnimalsCell LineCell SurvivalFerric CompoundsHumansMagnetite NanoparticlesMiceNeoplasm TransplantationParticle SizeTechnetiumArticlehttps://doi.org/10.1007/s40199-019-00241-yPubMed ID 30706223