{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,24]],"date-time":"2026-02-24T11:31:11Z","timestamp":1771932671627,"version":"3.50.1"},"reference-count":30,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2026,2,24]],"date-time":"2026-02-24T00:00:00Z","timestamp":1771891200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Northwestern University Clinical and Translational Sciences","award":["UL1TR001422"],"award-info":[{"award-number":["UL1TR001422"]}]},{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","award":["S10OD020118"],"award-info":[{"award-number":["S10OD020118"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100014989","name":"Chan Zuckerberg Initiative","doi-asserted-by":"publisher","award":["2020-225578"],"award-info":[{"award-number":["2020-225578"]}],"id":[{"id":"10.13039\/100014989","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000001","name":"Soft and Hybrid Nanotechnology Experimental (SHyNE) Resource","doi-asserted-by":"publisher","award":["NSF ECCS-2025633"],"award-info":[{"award-number":["NSF ECCS-2025633"]}],"id":[{"id":"10.13039\/100000001","id-type":"DOI","asserted-by":"publisher"}]},{"name":"National Cancer Institute Cancer Center","award":["P30 CA060553"],"award-info":[{"award-number":["P30 CA060553"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JFB"],"abstract":"<jats:p>Recombinant human bone morphogenic protein-2 (rhBMP-2) use in spinal fusion is limited by dose-dependent complications. Peptide amphiphile (PA) supramolecular polymers presenting a BMP-2\u2013binding epitope have previously been developed to reduce the rhBMP-2 dose required for successful fusion. We evaluated PA implant biodegradation and tissue clearance in a rat posterolateral spinal fusion model as a prerequisite to clinical safety studies. Twenty-three female Sprague\u2013Dawley rats underwent L4\u2013L5 fusion with gadolinium (Gd)-labeled PA implants. Longitudinal magnetic resonance imaging (MRI) was performed up to 13 weeks postoperatively, while the spine and filter organs were harvested for inductively coupled plasma mass spectrometry (ICP-MS) quantification of Gd at multiple time points. Gd concentration at the fusion site decreased from 71% of maximum to 19.5% at 13 weeks, and MRI showed a complete loss of Gd signal enhancement by 8 weeks. In peripheral organs, peak Gd accumulation was 3% in the liver at 4 weeks, declining to 1.4% at 13 weeks, while Gd remained below 0.05% in the spleen, lung, and blood at all time points. These data indicate PA implant localization, with robust degradation and clearance and minimal off-target accumulation, supporting its translational potential for spinal fusion applications.<\/jats:p>","DOI":"10.3390\/jfb17030107","type":"journal-article","created":{"date-parts":[[2026,2,24]],"date-time":"2026-02-24T10:14:44Z","timestamp":1771928084000},"page":"107","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Biodistribution and Biodegradation of an Osteoinductive Supramolecular Polymer Implant in a Rat Spinal Fusion Model"],"prefix":"10.3390","volume":"17","author":[{"given":"Jacqueline","family":"Inglis","sequence":"first","affiliation":[{"name":"Department of Orthopaedic Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alyssa","family":"Goodwin","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Steven","family":"Kurapaty","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"David M.","family":"Hiltzik","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-6901-1132","authenticated-orcid":false,"given":"Rahim","family":"Laiwalla","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hogan","family":"Brecount","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9135-1882","authenticated-orcid":false,"given":"Nicholas A.","family":"Sather","sequence":"additional","affiliation":[{"name":"Center for Regenerative Nanomedicine (CRN), Northwestern University, 303 E. Superior, Chicago, IL 60611, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3479-6054","authenticated-orcid":false,"given":"Emily A.","family":"Waters","sequence":"additional","affiliation":[{"name":"Center for Advanced Molecular Imaging in the Chemistry of Life Processes Institute and Biomedical Engineering, Northwestern University, Evanston, IL 60208, USA"},{"name":"Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chad R.","family":"Haney","sequence":"additional","affiliation":[{"name":"Center for Advanced Molecular Imaging in the Chemistry of Life Processes Institute and Biomedical Engineering, Northwestern University, Evanston, IL 60208, USA"},{"name":"Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208, USA"},{"name":"Department of Radiology, Northwestern University, Chicago, IL 60611, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rebecca","family":"Sponenburg","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Northwestern University, Evanston, IL 60208, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xinyi","family":"Lin","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wellington K.","family":"Hsu","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5491-7442","authenticated-orcid":false,"given":"Samuel I.","family":"Stupp","sequence":"additional","affiliation":[{"name":"Center for Regenerative Nanomedicine (CRN), Northwestern University, 303 E. Superior, Chicago, IL 60611, USA"},{"name":"Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208, USA"},{"name":"Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208, USA"},{"name":"Department of Materials Science and Engineering, Northwestern University, Evanston, IL 60208, USA"},{"name":"Department of Medicine, Northwestern University, Chicago, IL 60611, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Erin L.","family":"Hsu","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA"},{"name":"Center for Regenerative Nanomedicine (CRN), Northwestern University, 303 E. 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