{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,26]],"date-time":"2026-04-26T08:08:11Z","timestamp":1777190891174,"version":"3.51.4"},"reference-count":49,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2025,6,11]],"date-time":"2025-06-11T00:00:00Z","timestamp":1749600000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"AGH Initiative for Excellence\u2014Research University","award":["6795\/2023"],"award-info":[{"award-number":["6795\/2023"]}]},{"name":"AGH Initiative for Excellence\u2014Research University","award":["PLG\/2023\/016141"],"award-info":[{"award-number":["PLG\/2023\/016141"]}]},{"name":"high-performance Polish computing infrastructure PLGrid (HPC Centers: ACK Cyfronet AGH)","award":["6795\/2023"],"award-info":[{"award-number":["6795\/2023"]}]},{"name":"high-performance Polish computing infrastructure PLGrid (HPC Centers: ACK Cyfronet AGH)","award":["PLG\/2023\/016141"],"award-info":[{"award-number":["PLG\/2023\/016141"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>A tandem UV\u2013Vis and fluorescence spectroscopy method was developed for the detection of Pd(II) ions in ethanol. The formation of a complex between Pd(II) ions and tropaeolin OO (TR OO) is accompanied by a change in the color of the solution and evolution of the characteristic UV\u2013Vis as well as fluorescence spectra. The optimal detection conditions were achieved at a 3:1 (mL\/mL) volume ratio of Pd(II) to TR OO, at 50 \u00b0C. UV\u2013Vis spectroscopy enabled the detection of complex formation process over time, while fluorescence spectroscopy allowed a rapid response within 10 min. The limit of detection (LOD) of Pd(II) ions using UV\u2013Vis spectrophotometry was 10 \u03bcmol\/dm3 at 535 nm. For spectrofluorimetric detection, the LOD was 10 \u03bcmol\/dm3, with an emission signal observed at 630 nm after 10 min. The kinetics studies showed a stepwise complex formation pathway, supported by DFT calculations. The performance of the method was verified in the presence of interfering metal ions, including Li(I), Na(I), Al(III), Ni(II), Mg(II), Ca(II), Co(II), and Zn(II), confirming its applicability in complex matrices. This approach provides efficient palladium determination in organic solvents, contributing to sustainable practices in metal recycling.<\/jats:p>","DOI":"10.3390\/ijms26125613","type":"journal-article","created":{"date-parts":[[2025,6,11]],"date-time":"2025-06-11T11:18:40Z","timestamp":1749640720000},"page":"5613","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["High-Sensitivity Sensor for Palladium Detection in Organic Solvent"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2474-4835","authenticated-orcid":false,"given":"Adrianna","family":"Pach","sequence":"first","affiliation":[{"name":"AGH University of Krakow, Faculty of Non-Ferrous Metals, Al. A. Mickiewicza 30, 30-059 Krakow, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1233-7300","authenticated-orcid":false,"given":"Agnieszka","family":"Podborska","sequence":"additional","affiliation":[{"name":"AGH University of Krakow, Academic Centre for Materials and Nanotechnology, Al. A. Mickiewicza 30, 30-059 Krakow, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9018-7654","authenticated-orcid":false,"given":"Magdalena","family":"Luty-B\u0142ocho","sequence":"additional","affiliation":[{"name":"AGH University of Krakow, Faculty of Non-Ferrous Metals, Al. A. Mickiewicza 30, 30-059 Krakow, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,6,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"889","DOI":"10.1002\/adsc.200404071","article-title":"The Art of Meeting Palladium Specifications in Active Pharmaceutical Ingredients Produced by Pd-Catalyzed Reactions","volume":"346","author":"Garrett","year":"2004","journal-title":"Adv. Synth. Catal."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"3027","DOI":"10.1002\/adsc.200900587","article-title":"Recent Applications of Palladium\u2014Catalyzed Coupling Reactions in the Pharmaceutical, Agrochemical, and Fine Chemical Industries","volume":"351","author":"Torborg","year":"2009","journal-title":"Adv. Synth. 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