{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,17]],"date-time":"2026-09-17T05:02:34Z","timestamp":1789621354182,"version":"build-2803163510"},"reference-count":35,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2026,9,14]],"date-time":"2026-09-14T00:00:00Z","timestamp":1789344000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nanomaterials"],"abstract":"<jats:p>Phosphorus (P) contamination in agricultural runoff is a major environmental concern due to its contribution to eutrophication and deterioration of water quality. Ortho-phosphate extraction from aqueous model systems and agricultural runoff samples was investigated using cetyltrimethylammonium bromide-magnetic nanoparticles (CTAB-MNPs), sodium dodecylsulfate-magnetic nanoparticles (SDS-MNPs), and Mill scale. It was monitored using UV\u2013visible spectroscopy based on the molybdenum blue method, while the adsorption mechanism of P on MNPs was evaluated through time-dependent studies, FTIR, zeta potential (\u03b6), X-ray photoelectron spectroscopy (XPS), and FESEM-EDS. CTAB-MNPs promoted P adsorption through favorable electrostatic interactions between positively charged quaternary ammonium groups and negatively charged phosphate ions, while SDS-MNPs enhanced P uptake by improving nanoparticle dispersion, colloidal stability, and accessibility of iron oxide active sites. Time-dependent studies revealed that the adsorption kinetics followed the order SDS-MNPs &gt; Mill Scale &gt; CTAB-MNPs. IR, XPS, FESEM-EDS and \u03b6 analyses confirmed the presence of adsorbed P on the surface of MNPs. The results demonstrated that P removal was also governed by inner-sphere complexation with iron oxide active sites rather than electrostatic interactions alone, highlighting the potential of surfactant-modified MNPs and Mill scale as effective materials for P extraction from agricultural runoff.<\/jats:p>","DOI":"10.3390\/nano16181150","type":"journal-article","created":{"date-parts":[[2026,9,14]],"date-time":"2026-09-14T14:15:04Z","timestamp":1789395304000},"page":"1150","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Functional Magnetic Nanoparticles and Mill Scale for Phosphorus Extraction from Contaminated Water"],"prefix":"10.3390","volume":"16","author":[{"given":"Rajpreet","family":"Kaur","sequence":"first","affiliation":[{"name":"Department of Chemistry, Natural and Applied Sciences, University of Wisconsin-Green Bay, 2420 Nicolet Drive, Green Bay, WI 54311-7001, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mandeep Singh","family":"Bakshi","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Natural and Applied Sciences, University of Wisconsin-Green Bay, 2420 Nicolet Drive, Green Bay, WI 54311-7001, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"10002","DOI":"10.1073\/pnas.0503959102","article-title":"Eutrophication of aquatic ecosystems: Biostability and soil phosphorus","volume":"102","author":"Carpenter","year":"2005","journal-title":"Proc. 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