{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,9]],"date-time":"2026-11-09T16:37:13Z","timestamp":1794242233257,"version":"4.9.0"},"reference-count":44,"publisher":"American Chemical Society (ACS)","issue":"31","license":[{"start":{"date-parts":[[2026,7,31]],"date-time":"2026-07-31T00:00:00Z","timestamp":1785456000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004462","name":"Consiglio Nazionale delle Ricerche","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100004462","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100006256","name":"Universit\u00e0 degli Studi dell'Aquila","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100006256","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100021856","name":"Ministero dell'Universit\u00e0 e della Ricerca","doi-asserted-by":"publisher","award":["E13C22001060006"],"award-info":[{"award-number":["E13C22001060006"]}],"id":[{"id":"10.13039\/501100021856","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,8,11]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Graphene oxide (GO)-based nanomaterials have emerged as promising platforms in biomedicine, particularly for their potential use as carriers of magnetic resonance imaging (MRI) contrast agents (CAs). In this study, we investigate the MRI CA performance of reduced graphene oxide and its dependence on the degree of reduction. To ensure full control, GO was synthesized in-house via a modified Hummers\u2019 method and subsequently reduced by two distinct approaches: mild thermal reduction (rGO1) and selective chemical reduction with sodium borohydride (rGO2). Comprehensive physicochemical characterization, including Fourier-transform infrared (FTIR) spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy, differential scanning calorimetry, and thermogravimetric analysis (TGA), was performed to evaluate the structural changes induced by each reduction process. The MRI performance of GO, rGO1, and rGO2 was assessed at 1.0 T alongside electron paramagnetic resonance (EPR) measurements, while inductively coupled plasma-mass spectrometry (ICP-MS) quantified residual manganese and iron impurities. EPR and ICP-MS demonstrated that these impurities made a negligible contribution to the relaxivity. Our findings reveal a significant enhancement in MRI relaxivities with an increasing degree of reduction. Chemically reduced rGO2 exhibits the highest longitudinal relaxivity (r1), approximately 3.9-fold greater than that of pristine GO, and transverse relaxivity (r2), approximately 4.6-fold greater. Strong linear correlations between relaxivities and XPS-derived structural parameters, including the C\/O ratio and C\u2013C\/C\u2550C content, indicate that carbon structural defects govern MRI contrast performance. Overall, these results establish a framework for the rational design of rGO-based CAs through controlled reduction of two-dimensional carbon materials, enabling optimized imaging performance and supporting future biomedical translation.<\/jats:p>","DOI":"10.1021\/acsomega.6c04502","type":"journal-article","created":{"date-parts":[[2026,8,4]],"date-time":"2026-08-04T14:03:38Z","timestamp":1785852218000},"page":"46701-46710","source":"Crossref","is-referenced-by-count":1,"title":["Reduction-Driven\nModulation of Relaxivity in Graphene\nOxide Derivatives"],"prefix":"10.1021","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8653-9925","authenticated-orcid":true,"given":"Giulia","family":"Fioravanti","sequence":"first","affiliation":[{"name":"University of L\u2019Aquila , , ,","place":["L\u2019Aquila, Italy, 67100"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Laura","family":"Torrieri Di Tullio","sequence":"additional","affiliation":[{"name":"Istituto Superiore di Sanita\u0300 , Viale Regina Elena 299 , ,","place":["Rome, Italy, 00161"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Salvatore","family":"Mamone","sequence":"additional","affiliation":[{"name":"University of L\u2019Aquila , , ,","place":["L\u2019Aquila, Italy, 67100"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paola","family":"Fattibene","sequence":"additional","affiliation":[{"name":"Istituto Superiore di Sanita\u0300 , Viale Regina Elena 299 , ,","place":["Rome, Italy, 00161"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marcello","family":"Alecci","sequence":"additional","affiliation":[{"name":"University of L\u2019Aquila , , ,","place":["L\u2019Aquila, Italy, 67100"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Silvia","family":"Colacicchi","sequence":"additional","affiliation":[{"name":"University of L\u2019Aquila , , ,","place":["L\u2019Aquila, Italy, 67100"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3228-7785","authenticated-orcid":true,"given":"Angelo","family":"Galante","sequence":"additional","affiliation":[{"name":"University of L\u2019Aquila , , ,","place":["L\u2019Aquila, Italy, 67100"]},{"name":"National Institute for Nuclear Physics (INFN) , , ,","place":["L\u2019Aquila, Italy, 67100"]},{"name":"CNR-SPIN, c\/o Department of Physical and Chemical Sciences , ,","place":["L\u2019Aquila, Italy, 67100"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"316","published-online":{"date-parts":[[2026,7,31]]},"reference":[{"issue":"5","key":"2026081110144803800_cit1","doi-asserted-by":"publisher","first-page":"1517","DOI":"10.1039\/C9TC03251G","article-title":"Harvesting graphene oxide \u2013 years 1859 to 2019: a review of\nits structure, synthesis, properties and exfoliation","volume":"8","author":"Brisebois","year":"2020","journal-title":"J. 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