{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,24]],"date-time":"2026-03-24T00:35:09Z","timestamp":1774312509080,"version":"3.50.1"},"reference-count":44,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2025,3,13]],"date-time":"2025-03-13T00:00:00Z","timestamp":1741824000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>This study investigates the liquid crystalline behavior, photophysical properties, and metal ion sensing capabilities of a pyrene-based imine dimer (DPyH9). The compound exhibits monotropic nematic mesophase behavior, with a glass transition at 43 \u00b0C, as confirmed by polarized light microscopy (PLM) and differential scanning calorimetry (DSC). Its photophysical properties, including UV-vis absorption, solvatochromic fluorescence, and acidochromism, observed through spectral shifts upon HCl addition, were systematically analyzed. Notably, DPyH9 displayed selective metal ion sensing capabilities towards Sn2+ and Cu2+ with binding constants of 4.51 \u00d7 106 M\u22121 and 4.03 \u00d7 107 M\u22121 and detection limits of 1.61 \u00d7 10\u22125 M (Sn2+) and 4.73 \u00d7 10\u22125 M (Cu2+). Fluorescence titrations revealed distinct responses: Sn2+ induced an initial quenching and an enhancement at higher concentrations, while Cu2+ caused significant fluorescence quenching. These results therefore highlight DPyH9 as a potential candidate for sensing applications and optoelectronic devices.<\/jats:p>","DOI":"10.3390\/ijms26062566","type":"journal-article","created":{"date-parts":[[2025,3,13]],"date-time":"2025-03-13T04:18:32Z","timestamp":1741839512000},"page":"2566","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Photophysical Properties and Metal Ion Sensing of a Pyrene-Based Liquid Crystalline Dimer"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9432-5479","authenticated-orcid":false,"given":"Mihaela","family":"Homocianu","sequence":"first","affiliation":[{"name":"\u201cPetru Poni\u201d Institute of Macromolecular Chemistry, 41A, Grigore Ghica Voda Alley, 700487 Iasi, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2235-5198","authenticated-orcid":false,"given":"Elena","family":"Perju","sequence":"additional","affiliation":[{"name":"\u201cPetru Poni\u201d Institute of Macromolecular Chemistry, 41A, Grigore Ghica Voda Alley, 700487 Iasi, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,3,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"7975","DOI":"10.1039\/D0TC01939A","article-title":"Materials for the photoluminescent sensing of rare earth elements: Challenges and opportunities","volume":"8","author":"Crawford","year":"2020","journal-title":"J. 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