{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,21]],"date-time":"2026-10-21T22:53:07Z","timestamp":1792623187987,"version":"4.5.0"},"reference-count":39,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2018,3,21]],"date-time":"2018-03-21T00:00:00Z","timestamp":1521590400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"MAPIT","award":["FKZ 13N11092"],"award-info":[{"award-number":["FKZ 13N11092"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nanomaterials"],"abstract":"<jats:p>The optimization of iron oxide nanoparticles as tracers for magnetic particle imaging (MPI) alongside the development of data acquisition equipment and image reconstruction techniques is crucial for the required improvements in image resolution and sensitivity of MPI scanners. We present a large-scale water-based synthesis of multicore superparamagnetic iron oxide nanoparticles stabilized with dextran (MC-SPIONs). We also demonstrate the preparation of single core superparamagnetic iron oxide nanoparticles in organic media, subsequently coated with a poly(ethylene glycol) gallic acid polymer and phase transferred to water (SC-SPIONs). Our aim was to obtain long-term stable particles in aqueous media with high MPI performance. We found that the amplitude of the third harmonic measured by magnetic particle spectroscopy (MPS) at 10 mT is 2.3- and 5.8-fold higher than Resovist for the MC-SPIONs and SC-SPIONs, respectively, revealing excellent MPI potential as compared to other reported MPI tracer particle preparations. We show that the reconstructed MPI images of phantoms using optimized multicore and specifically single-core particles are superior to that of commercially available Resovist, which we utilize as a reference standard, as predicted by MPS.<\/jats:p>","DOI":"10.3390\/nano8040180","type":"journal-article","created":{"date-parts":[[2018,3,22]],"date-time":"2018-03-22T05:14:55Z","timestamp":1521695695000},"page":"180","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":30,"title":["Optimization of Iron Oxide Tracer Synthesis for Magnetic Particle Imaging"],"prefix":"10.3390","volume":"8","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4910-8173","authenticated-orcid":false,"given":"Sabina","family":"Ziemian","sequence":"first","affiliation":[{"name":"MR and CT Contrast Media Research, Bayer AG, D-13353 Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6245-9042","authenticated-orcid":false,"given":"Norbert","family":"L\u00f6wa","sequence":"additional","affiliation":[{"name":"Physikalisch-Technische Bundesanstalt, D-10587 Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Olaf","family":"Kosch","sequence":"additional","affiliation":[{"name":"Physikalisch-Technische Bundesanstalt, D-10587 Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daniel","family":"Bajj","sequence":"additional","affiliation":[{"name":"University of British Columbia, Vancouver, BC V6T 1Z3, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0608-1473","authenticated-orcid":false,"given":"Frank","family":"Wiekhorst","sequence":"additional","affiliation":[{"name":"Physikalisch-Technische Bundesanstalt, D-10587 Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gunnar","family":"Sch\u00fctz","sequence":"additional","affiliation":[{"name":"MR and CT Contrast Media Research, Bayer AG, D-13353 Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2018,3,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1214","DOI":"10.1038\/nature03808","article-title":"Tomographic imaging using the nonlinear response of magnetic particles","volume":"435","author":"Gleich","year":"2005","journal-title":"Nature"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1109\/TMAG.2017.2708419","article-title":"Characterizing a preclinical magnetic particle imaging system with separate pick-up coil","volume":"53","author":"Wells","year":"2017","journal-title":"IEEE Trans. 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