{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,2]],"date-time":"2026-04-02T12:54:39Z","timestamp":1775134479673,"version":"3.50.1"},"reference-count":27,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2020,3,18]],"date-time":"2020-03-18T00:00:00Z","timestamp":1584489600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100010665","name":"H2020 Marie Sk\u0142odowska-Curie Actions","doi-asserted-by":"publisher","award":["778078"],"award-info":[{"award-number":["778078"]}],"id":[{"id":"10.13039\/100010665","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002873","name":"Chulalongkorn University","doi-asserted-by":"publisher","award":["The 100th Anniversary Chulalongkorn University Fund for Doctoral Scholarship"],"award-info":[{"award-number":["The 100th Anniversary Chulalongkorn University Fund for Doctoral Scholarship"]}],"id":[{"id":"10.13039\/501100002873","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002873","name":"Chulalongkorn University","doi-asserted-by":"publisher","award":["The 90th Anniversary Chulalongkorn University Fund (Ratchadaphiseksomphot Endowment Fund)"],"award-info":[{"award-number":["The 90th Anniversary Chulalongkorn University Fund (Ratchadaphiseksomphot Endowment Fund)"]}],"id":[{"id":"10.13039\/501100002873","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["PTDC\/CTM-BIO\/4388\/ 2014 - SPARTAN"],"award-info":[{"award-number":["PTDC\/CTM-BIO\/4388\/ 2014 - SPARTAN"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["NORTE-01-0145-FEDER-000023 FROnTHERA"],"award-info":[{"award-number":["NORTE-01-0145-FEDER-000023 FROnTHERA"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["NORTE 2020 Structured Project"],"award-info":[{"award-number":["NORTE 2020 Structured Project"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biomolecules"],"abstract":"<jats:p>Accelerating the gelation of silk fibroin (SF) solution from several days or weeks to minutes or few hours is critical for several applications (e.g., cell encapsulation, bio-ink for 3D printing, and injectable controlled release). In this study, the rapid gelation of SF induced by a gold salt (Au3+) as well as the cytocompatibility of Au3+-mediated SF hydrogels are reported. The gelation behaviors and mechanisms of regenerated SF and thiolated SF (tSF) were compared. Hydrogels can be obtained immediately after mixing or within three days depending on the types of silk proteins used and amount of Au3+. Au3+-mediated SF and tSF hydrogels showed different color appearances. The color of Au-SF hydrogels was purple-red, whereas the Au-tSF hydrogels maintained their initial solution color, indicating different gelation mechanisms. The reduction of Au3+ by amino groups and further reduction to Au by tyrosine present in SF, resulting in a dityrosine bonding and Au nanoparticles (NPs) production, are proposed as underlying mechanisms of Au-SF gel formation. Thiol groups of the tSF reduced Au3+ to Au+ and formed a disulfide bond, before a formation of Au+-S bonds. Protons generated during the reactions between Au3+ and SF or tSF led to a decrease of the local pH, which affected the chain aggregation of the SF, and induced the conformational transition of SF protein to beta sheet. The cytocompatibility of the Au-SF and tSF hydrogels was demonstrated by culturing with a L929 cell line, indicating that the developed hydrogels can be promising 3D matrices for different biomedical applications.<\/jats:p>","DOI":"10.3390\/biom10030466","type":"journal-article","created":{"date-parts":[[2020,3,19]],"date-time":"2020-03-19T03:54:14Z","timestamp":1584590054000},"page":"466","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Exploring the Gelation Mechanisms and Cytocompatibility of Gold (III)-Mediated Regenerated and Thiolated Silk Fibroin Hydrogels"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5005-1701","authenticated-orcid":false,"given":"Chavee","family":"Laomeephol","sequence":"first","affiliation":[{"name":"Biomedical Engineering Research Center, Faculty of Engineering, Chulalongkorn University, Bangkok 10330, Thailand"},{"name":"Biomaterial Engineering for Medical and Health Research Unit, Faculty of Engineering, Chulalongkorn University, Bangkok 10330, Thailand"}]},{"given":"Helena","family":"Ferreira","sequence":"additional","affiliation":[{"name":"3B\u2019s Research Group, I3Bs-Research Institute on Biomaterials, Biodegradables and Biomimetics, University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, AvePark-Parque de Ci\u00eancia e Tecnologia, Zona Industrial da Gandra, 4805-017 Barco, Guimar\u00e3es, Portugal"},{"name":"ICVS\/3B\u2019s-PT Government Associate Laboratory, 4806-909 Braga\/Guimar\u00e3es, Portugal"}]},{"given":"Supansa","family":"Yodmuang","sequence":"additional","affiliation":[{"name":"Biomedical Engineering Research Center, Faculty of Engineering, Chulalongkorn University, Bangkok 10330, Thailand"},{"name":"Biomaterial Engineering for Medical and Health Research Unit, Faculty of Engineering, Chulalongkorn University, Bangkok 10330, Thailand"},{"name":"Research Affairs, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand"}]},{"given":"Rui L.","family":"Reis","sequence":"additional","affiliation":[{"name":"3B\u2019s Research Group, I3Bs-Research Institute on Biomaterials, Biodegradables and Biomimetics, University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, AvePark-Parque de Ci\u00eancia e Tecnologia, Zona Industrial da Gandra, 4805-017 Barco, Guimar\u00e3es, Portugal"},{"name":"ICVS\/3B\u2019s-PT Government Associate Laboratory, 4806-909 Braga\/Guimar\u00e3es, Portugal"},{"name":"The Discoveries Centre for Regenerative and Precision Medicine, Headquarters at University of Minho, Avepark, 4805-017 Barco, Guimar\u00e3es, Portugal"}]},{"given":"Siriporn","family":"Damrongsakkul","sequence":"additional","affiliation":[{"name":"Biomedical Engineering Research Center, Faculty of Engineering, Chulalongkorn University, Bangkok 10330, Thailand"},{"name":"Biomaterial Engineering for Medical and Health Research Unit, Faculty of Engineering, Chulalongkorn University, Bangkok 10330, Thailand"},{"name":"Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok 10330, Thailand"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3041-0687","authenticated-orcid":false,"given":"Nuno M.","family":"Neves","sequence":"additional","affiliation":[{"name":"3B\u2019s Research Group, I3Bs-Research Institute on Biomaterials, Biodegradables and Biomimetics, University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, AvePark-Parque de Ci\u00eancia e Tecnologia, Zona Industrial da Gandra, 4805-017 Barco, Guimar\u00e3es, Portugal"},{"name":"ICVS\/3B\u2019s-PT Government Associate Laboratory, 4806-909 Braga\/Guimar\u00e3es, Portugal"},{"name":"The Discoveries Centre for Regenerative and Precision Medicine, Headquarters at University of Minho, Avepark, 4805-017 Barco, Guimar\u00e3es, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2020,3,18]]},"reference":[{"key":"ref_1","unstructured":"Kundu, S.C. 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