{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,19]],"date-time":"2026-01-19T07:07:46Z","timestamp":1768806466442,"version":"3.49.0"},"reference-count":43,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2018,12,10]],"date-time":"2018-12-10T00:00:00Z","timestamp":1544400000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004329","name":"Javna Agencija za Raziskovalno Dejavnost RS","doi-asserted-by":"publisher","award":["1000-17-0552"],"award-info":[{"award-number":["1000-17-0552"]}],"id":[{"id":"10.13039\/501100004329","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Research Studios Austria project","award":["844724"],"award-info":[{"award-number":["844724"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The article presents naked-eye methods for fast, sensitive, and selective detection of isopentylamine and cadaverine vapours based on 4-N,N-dioctylamino-4\u2032-dicyanovinylazobenzene (CR-528) and 4-N,N-dioctylamino-2\u2032-nitro-4\u2032-dicyanovinylazobenzene (CR-555) dyes immobilized in ethylene-vinyl acetate copolymer (EVA). The reaction of CR-528\/EVA and CR-555\/EVA indicator layers with isopentylamine vapours caused a vivid colour change from pink\/purple to yellow\/orange-yellow. Additionally, CR-555\/EVA showed colour changes upon exposure to cadaverine. The colour changes were analysed by ultraviolet\u2013visible (UV\/VIS) molecular absorption spectroscopy for amine quantification, and the method was partially validated for the detection limit, sensitivity, and linear concentration range. The lowest detection limits were reached with CR-555\/EVA indicator layers (0.41 ppm for isopentylamine and 1.80 ppm for cadaverine). The indicator layers based on EVA and dicyanovinyl azobenzene dyes complement the existing library of colorimetric probes for the detection of biogenic amines and show great potential for food quality control.<\/jats:p>","DOI":"10.3390\/s18124361","type":"journal-article","created":{"date-parts":[[2018,12,10]],"date-time":"2018-12-10T11:31:16Z","timestamp":1544441476000},"page":"4361","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Indicator Layers Based on Ethylene-Vinyl Acetate Copolymer (EVA) and Dicyanovinyl Azobenzene Dyes for Fast and Selective Evaluation of Vaporous Biogenic Amines"],"prefix":"10.3390","volume":"18","author":[{"given":"Tinkara","family":"Mastnak","sequence":"first","affiliation":[{"name":"Institute for Environmental Protection and Sensors, Beloruska 7, SI-2000 Maribor, Slovenia"},{"name":"Faculty of Mechanical Engineering, University of Maribor, Smetanova ulica 17, 2000 Maribor, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Aleksandra","family":"Lobnik","sequence":"additional","affiliation":[{"name":"Institute for Environmental Protection and Sensors, Beloruska 7, SI-2000 Maribor, Slovenia"},{"name":"Faculty of Mechanical Engineering, University of Maribor, Smetanova ulica 17, 2000 Maribor, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Gerhard J.","family":"Mohr","sequence":"additional","affiliation":[{"name":"Joanneum Research Forschungsgesellschaft mbH\u2014Materials, Franz-Pichler-Stra\u00dfe 30, A-8160 Weiz, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Matja\u017e","family":"Fin\u0161gar","sequence":"additional","affiliation":[{"name":"Faculty of Chemistry and Chemical Engineering, University of Maribor, Smetanova ulica 17, 2000 Maribor, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,12,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1445","DOI":"10.1351\/pac200476071445","article-title":"Using light to control physical properties of polymers and surfaces with azobenzene chromophores","volume":"76","author":"Mermut","year":"2004","journal-title":"Pure Appl. 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