{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T18:57:19Z","timestamp":1790103439780,"version":"4.0.1"},"reference-count":58,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2025,5,11]],"date-time":"2025-05-11T00:00:00Z","timestamp":1746921600000},"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 method for the spectrophotometric determination of trace amounts of molybdenum has been developed. This method utilizes a centrifuge-less cloud point extraction (CL-CPE) in a mixed micellar (MM) system containing a nonionic surfactant (Triton X-114) and an ionic liquid (Aliquat\u00ae 336, A336). The chromophore chelating reagent employed was 4-nitrocatechol (4NC, H2L). This work marks its first application as a CPE reagent. Under the optimal conditions, Mo(VI) forms a yellow ternary complex with 4NC and A336, which can be represented by the formula (A336+)2[MoO2L2]. The method possesses the following characteristics: limit of detection (LOD) of 3.2 ng mL\u22121, linear range of 10.8\u2013580 ng\/mL, absorption maximum of 435 nm, molar absorptivity coefficient of 3.34 \u00d7 105 L mol\u22121 cm\u22121, and Sandell\u2019s sensitivity of 0.29 ng cm\u22122. The method has been successfully employed for the determination of molybdenum in reference standard steel samples, bottled mineral water, and a molybdenum-containing dietary supplement.<\/jats:p>","DOI":"10.3390\/ijms26104597","type":"journal-article","created":{"date-parts":[[2025,5,12]],"date-time":"2025-05-12T10:58:07Z","timestamp":1747047487000},"page":"4597","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["An Ionic Liquid-Assisted Mixed Micelle-Mediated Centrifuge-Less Cloud Point Extraction Spectrophotometric Method for the Determination of Molybdenum(VI)"],"prefix":"10.3390","volume":"26","author":[{"given":"Vidka","family":"Divarova","sequence":"first","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\/0009-0002-5083-2975","authenticated-orcid":false,"given":"Andrea","family":"Gajdo\u0161ov\u00e1","sequence":"additional","affiliation":[{"name":"Department of Analytical Chemistry, Faculty of Science, Pavol Jozef \u0160af\u00e1rik University in Ko\u0161ice, SK-04154 Ko\u0161ice, 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"}]},{"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":[[2025,5,11]]},"reference":[{"key":"ref_1","unstructured":"Supuran, C.T., and Donald, W.A. 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