{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,5]],"date-time":"2026-10-05T20:34:33Z","timestamp":1791232473484,"version":"4.1.0"},"reference-count":34,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2020,10,1]],"date-time":"2020-10-01T00:00:00Z","timestamp":1601510400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100015622","name":"Ministerul Cercet\u0103rii \u015fi Inov\u0103rii","doi-asserted-by":"publisher","award":["11\/2018, Code Project ERANET-INCOMERA-AGRO-SMARTGEL"],"award-info":[{"award-number":["11\/2018, Code Project ERANET-INCOMERA-AGRO-SMARTGEL"]}],"id":[{"id":"10.13039\/501100015622","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Promoting Transnational Research Projects for Small and Medium Enterprises Framework\u2013Operational Program Western Greece 2014\u20132020","award":["5021383"],"award-info":[{"award-number":["5021383"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>The study aims at reusing and recycling the protein hide waste from the leather industry in ecological conditions by elaborating an innovative procedure in order to obtain a collagen matrix functionalized with nitrogen, phosphorus, and potassium (NPK) nutrients to be used for preparing smart fertilizers. This is an interdisciplinary approach, as it starts from hide waste raw material as a critical industrial waste, which is then subjected to several technological steps by selection of optimal processing parameters, followed by product fabrication at the laboratory, and next scales to the industrial pilot plant to obtain novel agro-hydrogels. In this context, the technology scheme for collagen hydrolysate with encapsulated nutrients was proposed and the process parameters were optimized by functionalization of agro-hydrogels with various natural and synthetic polymers, such as polyacrylamide, poly(sodium 4-styrenesulfonate-co-glycidyl methacrylate) copolymer, starch or dolomite. Based on the laboratory experiments, a pilot plant was constructed and tested. Taking as reference the collagen hydrolysate with encapsulated nutrients, the new fertilizers were adequately characterized by chemical analysis, determination of biodegradability and the degree of release of oxidable compounds in water. Based on the biodegradation mechanism and kinetic analysis of oxidable compounds release, adequate arguments are evidenced to demonstrate that these fertilizers can be applied for amendment of poor agricultural soils.<\/jats:p>","DOI":"10.3390\/ma13194396","type":"journal-article","created":{"date-parts":[[2020,10,1]],"date-time":"2020-10-01T20:18:28Z","timestamp":1601583508000},"page":"4396","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":21,"title":["Collagen-Based Hydrogels Composites from Hide Waste to Produce Smart Fertilizers"],"prefix":"10.3390","volume":"13","author":[{"given":"Daniela Simina","family":"Stefan","sequence":"first","affiliation":[{"name":"Department of Analytical Chemistry and Environmental Engineering, Faculty of Applied Chemistry and Materials Science, University Politehnica of Bucharest, 1-7 Polizu str., RO-011061 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gabriel","family":"Zainescu","sequence":"additional","affiliation":[{"name":"National R&amp;D Research Institute for Textile and Leather Division: Leather and Footwear Research Institute, 93 Ion Minulescu str., RO-031215 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1570-564X","authenticated-orcid":false,"given":"Ana-Maria","family":"Manea-Saghin","sequence":"additional","affiliation":[{"name":"Research Center for Environmental Protection and Eco-Friendly Technologies, Faculty of Applied Chemistry and Materials Science, University Politehnica of Bucharest, 1\u20137 Polizu str., RO-011061 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Irene-Eva","family":"Triantaphyllidou","sequence":"additional","affiliation":[{"name":"Department of Chemical Engineering, University of Patras, Rio, GR-26504 Patras, Greece"},{"name":"Foundation for Research and Technology-Hellas (FORTH)\/Institute of Chemical Engineering Sciences (ICE-HT), Stadiou Str., Platani, GR-26504 Patras, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ioanna","family":"Tzoumani","sequence":"additional","affiliation":[{"name":"Foundation for Research and Technology-Hellas (FORTH)\/Institute of Chemical Engineering Sciences (ICE-HT), Stadiou Str., Platani, GR-26504 Patras, Greece"},{"name":"Department of Chemistry, University of Patras, GR-26504 Patras, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2527-0544","authenticated-orcid":false,"given":"Triantafyllos I.","family":"Tatoulis","sequence":"additional","affiliation":[{"name":"Sirmet SA, Engineering and Management, 4-6 Filopoimenos str., 26221 Patras, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"George T.","family":"Syriopoulos","sequence":"additional","affiliation":[{"name":"Sirmet SA, Engineering and Management, 4-6 Filopoimenos str., 26221 Patras, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aurelia","family":"Meghea","sequence":"additional","affiliation":[{"name":"Research Center for Environmental Protection and Eco-Friendly Technologies, Faculty of Applied Chemistry and Materials Science, University Politehnica of Bucharest, 1\u20137 Polizu str., RO-011061 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,10,1]]},"reference":[{"key":"ref_1","first-page":"90","article-title":"A new concept of complex valorization of leather wastes","volume":"51","author":"Zainescu","year":"2014","journal-title":"Mater. 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