{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T18:57:24Z","timestamp":1790103444648,"version":"4.0.1"},"reference-count":70,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2026,7,14]],"date-time":"2026-07-14T00:00:00Z","timestamp":1783987200000},"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>A novel centrifuge-less cloud-point extraction (CL-CPE) method based on pyrogallol (PG) was developed for the spectrophotometric determination of total vanadium. The method employs a mixed micelle-mediated extraction system comprising the nonionic surfactant Triton X-114 and the ionic liquid Aliquat 336 (A336), which serves as a source of monovalent cations capable of forming an ion pair with the anionic vanadium\u2013PG chelate. The extracted species, (A336+)[VIV(OH)(PG)2], exhibits several absorption maxima (309, 362, and 436 nm), providing enhanced selectivity through appropriate wavelength selection according to the sample matrix. The principal absorption maximum occurs at 309 nm. At a sevenfold preconcentration factor, the method provides high sensitivity at this wavelength, with a molar absorptivity of 3.2 \u00d7 107 L mol\u22121 cm\u22121, a limit of detection of 0.11 ng mL\u22121, and a Sandell sensitivity of 1.6 \u00d7 10\u22123 ng cm\u22122. The applicability of the method was demonstrated through the analysis of drinking water samples, spent vanadium catalyst materials, and vanadium-containing dietary supplements. The method was further evaluated using the RGBfast model, a white analytical chemistry assessment tool that integrates analytical performance, environmental sustainability, and practical and economic efficiency. The evaluation indicated a high overall whiteness score.<\/jats:p>","DOI":"10.3390\/ijms27146279","type":"journal-article","created":{"date-parts":[[2026,7,15]],"date-time":"2026-07-15T03:06:52Z","timestamp":1784084812000},"page":"6279","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["A Sensitive Cloud Point Extraction\u2013Spectrophotometric Determination of Vanadium Using Pyrogallol and Aliquat 336"],"prefix":"10.3390","volume":"27","author":[{"ORCID":"https:\/\/orcid.org\/0009-0002-5083-2975","authenticated-orcid":false,"given":"Andrea","family":"Gajdo\u0161ov\u00e1","sequence":"first","affiliation":[{"name":"Department of Analytical Chemistry, Institute of Chemistry, Faculty of Science, Pavol Jozef \u0160af\u00e1rik University in Ko\u0161ice, Moyzesova 11, 04154 Kosice, Slovakia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3941-2072","authenticated-orcid":false,"given":"Petya","family":"Racheva","sequence":"additional","affiliation":[{"name":"Department of Chemical Sciences, Faculty of Pharmacy, Medical University of Plovdiv, 120 Buxton Bros Str., 4004 Plovdiv, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Antoaneta","family":"Saravanska","sequence":"additional","affiliation":[{"name":"Department of Chemical Sciences, Faculty of Pharmacy, Medical University of Plovdiv, 120 Buxton Bros Str., 4004 Plovdiv, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0407-6171","authenticated-orcid":false,"given":"Jana","family":"\u0160andrejov\u00e1","sequence":"additional","affiliation":[{"name":"Department of Analytical Chemistry, Institute of Chemistry, Faculty of Science, Pavol Jozef \u0160af\u00e1rik University in Ko\u0161ice, Moyzesova 11, 04154 Kosice, Slovakia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1360-8977","authenticated-orcid":false,"given":"Kiril","family":"Gavazov","sequence":"additional","affiliation":[{"name":"Department of Chemical Sciences, Faculty of Pharmacy, Medical University of Plovdiv, 120 Buxton Bros Str., 4004 Plovdiv, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"527","DOI":"10.1002\/bit.70115","article-title":"A Comprehensive Review of Pyrogallol: From Fundamental Chemistry to Advanced Applications and Toxicological Insights","volume":"123","author":"Park","year":"2026","journal-title":"Biotechnol. 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