{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,24]],"date-time":"2026-03-24T14:41:08Z","timestamp":1774363268054,"version":"3.50.1"},"reference-count":45,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2010,4,15]],"date-time":"2010-04-15T00:00:00Z","timestamp":1271289600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Aqueous biphasic systems (ABS) provide an alternative and efficient approach for the extraction, recovery and purification of biomolecules through their partitioning between two liquid aqueous phases. In this work, the ability of hydrophilic phosphonium-based ionic liquids (ILs) to form ABS with aqueous K3PO4 solutions was evaluated for the first time. Ternary phase diagrams, and respective tie-lines and tie-lines length, formed by distinct phosphonium-based ILs, water, and K3PO4 at 298 K, were measured and are reported. The studied phosphonium-based ILs have shown to be more effective in promoting ABS compared to the imidazolium-based counterparts with similar anions. Moreover, the extractive capability of such systems was assessed for distinct biomolecules (including amino acids, food colourants and alkaloids). Densities and viscosities of both aqueous phases, at the mass fraction compositions used for the biomolecules extraction, were also determined. The evaluated IL-based ABS have been shown to be prospective extraction media, particularly for hydrophobic biomolecules, with several advantages over conventional polymer-inorganic salt ABS.<\/jats:p>","DOI":"10.3390\/ijms11041777","type":"journal-article","created":{"date-parts":[[2010,4,15]],"date-time":"2010-04-15T10:51:29Z","timestamp":1271328689000},"page":"1777-1791","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":180,"title":["Extraction of Biomolecules Using Phosphonium-Based Ionic Liquids + K3PO4 Aqueous Biphasic Systems"],"prefix":"10.3390","volume":"11","author":[{"given":"Cl\u00e1udia L. S.","family":"Louros","sequence":"first","affiliation":[{"name":"Departamento de Qu\u00edmica, CICECO, Universidade de Aveiro, 3810-193 Aveiro, Portugal"}]},{"given":"Ana Filipa M.","family":"Cl\u00e1udio","sequence":"additional","affiliation":[{"name":"Departamento de Qu\u00edmica, CICECO, Universidade de Aveiro, 3810-193 Aveiro, Portugal"}]},{"given":"Catarina M. S. S.","family":"Neves","sequence":"additional","affiliation":[{"name":"Departamento de Qu\u00edmica, CICECO, Universidade de Aveiro, 3810-193 Aveiro, Portugal"}]},{"given":"Mara G.","family":"Freire","sequence":"additional","affiliation":[{"name":"Departamento de Qu\u00edmica, CICECO, Universidade de Aveiro, 3810-193 Aveiro, Portugal"}]},{"given":"Isabel M.","family":"Marrucho","sequence":"additional","affiliation":[{"name":"Departamento de Qu\u00edmica, CICECO, Universidade de Aveiro, 3810-193 Aveiro, Portugal"},{"name":"Instituto de Tecnologia Qu\u00edmica e Biol\u00f3gica, UNL, Av. Rep\u00fablica, Ap. 127, 2780-901 Oeiras, Portugal"}]},{"given":"J\u00e9r\u00f4me","family":"Pauly","sequence":"additional","affiliation":[{"name":"Laboratoire Haute Pression Centre Universitaire de Recherche Scientifique, Universit\u00e9 de Pau, Avenue de l\u2019Universit\u00e9, 64000 Pau, France"}]},{"given":"Jo\u00e3o A. P.","family":"Coutinho","sequence":"additional","affiliation":[{"name":"Departamento de Qu\u00edmica, CICECO, Universidade de Aveiro, 3810-193 Aveiro, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2010,4,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"709","DOI":"10.1038\/182709a0","article-title":"Partitioning of Proteins in Liquid Polymer-Polymer Two-Phase Systems","volume":"182","author":"Albertsson","year":"1958","journal-title":"Nature"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"269","DOI":"10.1385\/MB:19:3:269","article-title":"Aqueous Two-Phase Systems: A General Overview","volume":"19","year":"2001","journal-title":"Mol. 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