{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,16]],"date-time":"2026-10-16T17:56:39Z","timestamp":1792173399503,"version":"4.4.0"},"reference-count":27,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2023,9,12]],"date-time":"2023-09-12T00:00:00Z","timestamp":1694476800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Thailand Science Research and Innovation Fund","award":["CU_FRB65_hea (73)_167_21_33"],"award-info":[{"award-number":["CU_FRB65_hea (73)_167_21_33"]}]},{"name":"Thailand Science Research and Innovation Fund","award":["B05F640156"],"award-info":[{"award-number":["B05F640156"]}]},{"DOI":"10.13039\/501100002873","name":"Chulalongkorn University","doi-asserted-by":"publisher","award":["CU_FRB65_hea (73)_167_21_33"],"award-info":[{"award-number":["CU_FRB65_hea (73)_167_21_33"]}],"id":[{"id":"10.13039\/501100002873","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002873","name":"Chulalongkorn University","doi-asserted-by":"publisher","award":["B05F640156"],"award-info":[{"award-number":["B05F640156"]}],"id":[{"id":"10.13039\/501100002873","id-type":"DOI","asserted-by":"publisher"}]},{"name":"NSRF via the Program Management Unit for Human Resources and Institutional Development, Research, and Innovation","award":["CU_FRB65_hea (73)_167_21_33"],"award-info":[{"award-number":["CU_FRB65_hea (73)_167_21_33"]}]},{"name":"NSRF via the Program Management Unit for Human Resources and Institutional Development, Research, and Innovation","award":["B05F640156"],"award-info":[{"award-number":["B05F640156"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>Gamma irradiation, which is one of the more conventional sterilization methods, was used to induce the hydrogelation of silk fibroin in this study. The physical and chemical characteristics of the irradiation-induced silk fibroin hydrogels were investigated. Silk fibroin solution with a concentration greater than 1 wt% formed hydrogel when irradiated by gamma rays at a dose of 25 or 50 kGy. The hydrogel induced by 50 kGy of radiation was more thermally stable at 80 \u00b0C than those induced by 25 kGy of radiation. When compared to the spontaneously formed hydrogels, the irradiated hydrogels contained a greater fraction of random coils and a lower fraction of \u03b2-sheets. This finding implies that gelation via gamma irradiation occurs via other processes, in addition to crystalline \u03b2\u2013sheet formation, which is a well-established mechanism. Our observation suggests that crosslinking and chain scission via gamma irradiation could occur in parallel with the \u03b2\u2013sheet formation. The irradiation-induced hydrogels were obtained when the solution concentration was adequate to support the radiation crosslinking of the silk fibroin chains. This work has, therefore, demonstrated that gamma irradiation can be employed as an alternative method to produce chemical-free, random coil-rich, and sterilized silk fibroin hydrogels for biomedical applications.<\/jats:p>","DOI":"10.3390\/polym15183734","type":"journal-article","created":{"date-parts":[[2023,9,12]],"date-time":"2023-09-12T03:54:06Z","timestamp":1694490846000},"page":"3734","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":21,"title":["Hydrogelation of Regenerated Silk Fibroin via Gamma Irradiation"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9074-784X","authenticated-orcid":false,"given":"Peerapat","family":"Thongnuek","sequence":"first","affiliation":[{"name":"Center of Excellence in Biomaterial Engineering for Medical and Health, Chulalongkorn University, Bangkok 10330, Thailand"},{"name":"Biomedical Engineering Program, Faculty of Engineering, Chulalongkorn University, Bangkok 10330, Thailand"},{"name":"Biomedical Engineering Research Center, Faculty of Engineering, Chulalongkorn University, Bangkok 10330, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sorada","family":"Kanokpanont","sequence":"additional","affiliation":[{"name":"Center of Excellence in Biomaterial Engineering for Medical and Health, Chulalongkorn University, Bangkok 10330, Thailand"},{"name":"Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok 10330, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8196-2185","authenticated-orcid":false,"given":"Pimpon","family":"Uttayarat","sequence":"additional","affiliation":[{"name":"Research and Development Unit, Thailand Institute of Nuclear Technology (Public Organization), Nakhon Nayok 26120, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Siriporn","family":"Damrongsakkul","sequence":"additional","affiliation":[{"name":"Center of Excellence in Biomaterial Engineering for Medical and Health, Chulalongkorn University, Bangkok 10330, Thailand"},{"name":"Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok 10330, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,9,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.actbio.2015.09.005","article-title":"Silk fibroin as biomaterial for bone tissue engineering","volume":"31","author":"Melke","year":"2016","journal-title":"Acta Biomater."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"401","DOI":"10.1016\/S0142-9612(02)00353-8","article-title":"Silk-based biomaterials","volume":"24","author":"Altman","year":"2003","journal-title":"Biomaterials"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"3151","DOI":"10.1007\/s10856-010-4159-5","article-title":"Tissue response and biodegradation of composite scaffolds prepared from Thai silk fibroin, gelatin and hydroxyapatite","volume":"21","author":"Tungtasana","year":"2010","journal-title":"J. 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