{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,17]],"date-time":"2026-03-17T04:49:03Z","timestamp":1773722943686,"version":"3.50.1"},"reference-count":50,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2021,4,15]],"date-time":"2021-04-15T00:00:00Z","timestamp":1618444800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"FCT","doi-asserted-by":"publisher","award":["UIDB\/04138\/2020"],"award-info":[{"award-number":["UIDB\/04138\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"FCT","doi-asserted-by":"publisher","award":["UIDP\/04138\/2020 and UIDB\/0100\/2020"],"award-info":[{"award-number":["UIDP\/04138\/2020 and UIDB\/0100\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"FCT","doi-asserted-by":"publisher","award":["IF\/00841\/2012"],"award-info":[{"award-number":["IF\/00841\/2012"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Young Investigator Award 2018 (iMed.Ulisboa)","award":["2018"],"award-info":[{"award-number":["2018"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Insulin is a peptide hormone with many physiological functions, besides its use in diabetes treatment. An important role of insulin is related to the wound healing process\u2014however, insulin itself is too sensitive to the external environment requiring the protective of a nanocarrier. Polymer-based nanoparticles can protect, deliver, and retain the protein in the target area. This study aims to produce and characterize a topical treatment for wound healing consisting of insulin-loaded poly-DL-lactide\/glycolide (PLGA) nanoparticles. Insulin-loaded nanoparticles present a mean size of approximately 500 nm and neutral surface charge. Spherical shaped nanoparticles are observed by scanning electron microscopy and confirmed by atomic force microscopy. SDS-PAGE and circular dichroism analysis demonstrated that insulin preserved its integrity and secondary structure after the encapsulation process. In vitro release studies suggested a controlled release profile. Safety of the formulation was confirmed using cell lines, and cell viability was concentration and time-dependent. Preliminary safety in vivo assays also revealed promising results.<\/jats:p>","DOI":"10.3390\/ijms22084087","type":"journal-article","created":{"date-parts":[[2021,4,15]],"date-time":"2021-04-15T12:11:00Z","timestamp":1618488660000},"page":"4087","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Development of a Topical Insulin Polymeric Nanoformulation for Skin Burn Regeneration: An Experimental Approach"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7045-1873","authenticated-orcid":false,"given":"Maria","family":"Quit\u00e9rio","sequence":"first","affiliation":[{"name":"iMed., ULisboa, Research Institute for Medicines, Faculty of Pharmacy, Universidade de Lisboa, 1649-003 Lisboa, Portugal"}]},{"given":"Sandra","family":"Sim\u00f5es","sequence":"additional","affiliation":[{"name":"iMed., ULisboa, Research Institute for Medicines, Faculty of Pharmacy, Universidade de Lisboa, 1649-003 Lisboa, Portugal"}]},{"given":"Andreia","family":"Ascenso","sequence":"additional","affiliation":[{"name":"iMed., ULisboa, Research Institute for Medicines, Faculty of Pharmacy, Universidade de Lisboa, 1649-003 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6028-4717","authenticated-orcid":false,"given":"Manuela","family":"Carvalheiro","sequence":"additional","affiliation":[{"name":"iMed., ULisboa, Research Institute for Medicines, Faculty of Pharmacy, Universidade de Lisboa, 1649-003 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2946-9342","authenticated-orcid":false,"given":"Ana Paula","family":"Leandro","sequence":"additional","affiliation":[{"name":"iMed., ULisboa, Research Institute for Medicines, Faculty of Pharmacy, Universidade de Lisboa, 1649-003 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7096-4284","authenticated-orcid":false,"given":"Isabel","family":"Correia","sequence":"additional","affiliation":[{"name":"Centro de Qu\u00edmica Estrutural, Instituto Superior T\u00e9cnico, Departamento de Engenharia Qu\u00edmica, Universidade de Lisboa, 1049-001 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8405-9672","authenticated-orcid":false,"given":"Ana Silveira","family":"Viana","sequence":"additional","affiliation":[{"name":"Centro de Qu\u00edmica Estrutural, Faculdade de Ci\u00eancias, Universidade de Lisboa, 1749-016 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3922-3602","authenticated-orcid":false,"given":"Pedro","family":"Fa\u00edsca","sequence":"additional","affiliation":[{"name":"Faculdade de Medicina Veterin\u00e1ria, Universidade Lus\u00f3fona de Humanidades e Tecnologias, 1794-024 Lisboa, Portugal"},{"name":"CBIOS-Research Center for Biosciences &amp; Health Technologies, Universidade Lus\u00f3fona de Humanidades e Tecnologias, 1794-024 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7439-5912","authenticated-orcid":false,"given":"Lia","family":"Ascens\u00e3o","sequence":"additional","affiliation":[{"name":"Centro de Estudos do Ambiente e do Mar (CESAM), Faculdade de Ci\u00eancias, Universidade de Lisboa, 1749-016 Lisboa, Portugal"}]},{"given":"Jes\u00fas","family":"Molpeceres","sequence":"additional","affiliation":[{"name":"Department of Biomedical Sciences, Faculty of Pharmacy, University of Alcal\u00e1, Campus Universitario, 28871 Alcal\u00e1 de Henares, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6814-7226","authenticated-orcid":false,"given":"Maria Manuela","family":"Gaspar","sequence":"additional","affiliation":[{"name":"iMed., ULisboa, Research Institute for Medicines, Faculty of Pharmacy, Universidade de Lisboa, 1649-003 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1046-4031","authenticated-orcid":false,"given":"Catarina Pinto","family":"Reis","sequence":"additional","affiliation":[{"name":"iMed., ULisboa, Research Institute for Medicines, Faculty of Pharmacy, Universidade de Lisboa, 1649-003 Lisboa, Portugal"},{"name":"IBEB, Biophysics and Biomedical Engineering, Faculdade de Ci\u00eancias, Universidade de Lisboa, 1749-016 Lisboa, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2021,4,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"94","DOI":"10.1016\/j.jcma.2017.11.002","article-title":"Wound healing","volume":"81","author":"Wang","year":"2018","journal-title":"J. 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