{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,7]],"date-time":"2026-04-07T09:50:36Z","timestamp":1775555436314,"version":"3.50.1"},"reference-count":37,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,4,7]],"date-time":"2026-04-07T00:00:00Z","timestamp":1775520000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"The Ministry of Research, Innovation and Digitization","award":["PN-IV-P2-2.1-TE-2023-1206"],"award-info":[{"award-number":["PN-IV-P2-2.1-TE-2023-1206"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Gels"],"abstract":"<jats:p>In the current study, bioactive-loaded hydrogels were developed with k-carrageenan (1%), and water was replaced with infusions of Urtica dioica L., which modulated the polymer chains to create more robust networks. Urtica dioica L. infusions were obtained with different infusion durations (5 or 10 min) or plant-to-water ratios (0.4, 1, or 2 g\/100 mL). The hydrogels were characterized for stability by assessing the syneresis rate and textural and rheological attributes. To elucidate the influence of the infusion on the mechanisms of k-carragenan, temperature ramp tests were applied and FTIR spectra were acquired. Replacing water with Urtica dioica L. infusions for obtaining k-carrageenan hydrogels led to lower syneresis rates (3.34 \u00b1 0.03% and 6.67 \u00b1 0.33%), while the hydrogels showed increased hardness, but lower resilience and cohesiveness. The rheological parameters confirmed the reinforcement; higher G\u2032 and gelling temperatures were registered compared to the reference. While FTIR spectra showed that the primary chemical backbone remained intact, the physicochemical changes indicate a strong physical synergy between nettle polyphenols and the \u03ba-carrageenan chains. Of all samples, the highest antioxidant potential value of 94.66% was exhibited by the infusion obtained in 15 min with a ratio of plant material of 2\/100 g. These findings demonstrate that plant-to-water ratios and infusion times are critical parameters for tuning the physical properties and biological efficacy of hydrogels for medical or food applications.<\/jats:p>","DOI":"10.3390\/gels12040313","type":"journal-article","created":{"date-parts":[[2026,4,7]],"date-time":"2026-04-07T08:09:00Z","timestamp":1775549340000},"page":"313","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["The Influence of Stinging Nettle (Urtica dioica L.) Infusions on the Techno-Functionality of k-Carrageenan Hydrogels"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1253-2592","authenticated-orcid":false,"given":"Andreea","family":"Pu\u0219ca\u0219","sequence":"first","affiliation":[{"name":"Food Engineering Department, Faculty of Food Science and Technology, University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, 400372 Cluj-Napoca, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Cristian","family":"Szekely","sequence":"additional","affiliation":[{"name":"Food Engineering Department, Faculty of Food Science and Technology, University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, 400372 Cluj-Napoca, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Flavius George","family":"Viorel","sequence":"additional","affiliation":[{"name":"Food Engineering Department, Faculty of Food Science and Technology, University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, 400372 Cluj-Napoca, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alexandra Raluca","family":"Laz\u0103r","sequence":"additional","affiliation":[{"name":"Food Engineering Department, Faculty of Food Science and Technology, University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, 400372 Cluj-Napoca, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9136-4832","authenticated-orcid":false,"given":"Anda Elena","family":"Tanislav","sequence":"additional","affiliation":[{"name":"Food Engineering Department, Faculty of Food Science and Technology, University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, 400372 Cluj-Napoca, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Andru\u021ba Elena","family":"Mure\u0219an","sequence":"additional","affiliation":[{"name":"Food Engineering Department, Faculty of Food Science and Technology, University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, 400372 Cluj-Napoca, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2113-422X","authenticated-orcid":false,"given":"Vlad","family":"Mure\u0219an","sequence":"additional","affiliation":[{"name":"Food Engineering Department, Faculty of Food Science and Technology, University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, 400372 Cluj-Napoca, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1927","DOI":"10.1007\/s10562-021-03803-5","article-title":"Fructooligosaccharides production from inulin by immobilized endoinulinase on 3-aminopropyltriethoxysilane functionalized halloysite nanoclay","volume":"152","author":"Singh","year":"2021","journal-title":"Catal. 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