{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,28]],"date-time":"2026-01-28T22:35:46Z","timestamp":1769639746369,"version":"3.49.0"},"reference-count":47,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2021,4,16]],"date-time":"2021-04-16T00:00:00Z","timestamp":1618531200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100006407","name":"Natural Science Foundation of Henan Province","doi-asserted-by":"publisher","award":["182102310728"],"award-info":[{"award-number":["182102310728"]}],"id":[{"id":"10.13039\/501100006407","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Foundation of Henan Polytechnic University","award":["NSFRF200313"],"award-info":[{"award-number":["NSFRF200313"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Baicalin which has multiple biological activities is the main active component of the root of Scutellaria baicalensis Georgi (SBG). Although its isolation and purification by adsorption methods have aroused much interest of the scientific community, it suffered from the poor selectivity of the adsorbents. In this work, an environmentally benign method was developed to prepare ionic liquids (ILs) grafted silica by using IL 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([C4mim]NTf2) and ethanol as reaction media. The IL 1-propyl-3-methylimidazolium chloride ([C3mim]Cl) grafted silica ([C3mim]+Cl\u2212@SiO2) was used to adsorb and purify baicalin from the root extract of Scutellaria baicalensis Georgi (SBG). Experimental results indicated that the adsorption equilibrium can be quickly achieved (within 10 min). The adsorption behavior of [C3mim]+Cl\u2212@SiO2 for baicalin was in good agreement with Langmuir and Freundlich models and the adsorption was a physisorption process as suggested by Dubinin\u2013Radushkevich model. Compared with commercial resins, [C3mim]+Cl\u2212@SiO2 showed the strongest adsorption ability and highest selectivity. After desorption and crystallization, a purity of baicalin as high as 96.5% could be obtained. These results indicated that the ILs grafted silica materials were promising adsorbents for the adsorption and purification of baicalin and showed huge potential in the purification of other bioactive compounds from natural sources.<\/jats:p>","DOI":"10.3390\/molecules26082322","type":"journal-article","created":{"date-parts":[[2021,4,19]],"date-time":"2021-04-19T06:35:53Z","timestamp":1618814153000},"page":"2322","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Adsorption and Purification of Baicalin from Scutellaria baicalensis Georgi Extract by Ionic Liquids (ILs) Grafted Silica"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4237-9242","authenticated-orcid":false,"given":"Yunchang","family":"Fan","sequence":"first","affiliation":[{"name":"College of Chemistry and Chemical Engineering, Henan Polytechnic University, Jiaozuo 454003, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Di","family":"Wu","sequence":"additional","affiliation":[{"name":"College of Chemistry and Chemical Engineering, Henan Polytechnic University, Jiaozuo 454003, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sheli","family":"Zhang","sequence":"additional","affiliation":[{"name":"College of Science and Technology, Jiaozuo Teachers College, Jiaozuo 454000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,4,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"9","DOI":"10.1002\/food.200200230","article-title":"Antimutagenic and antiradical properties of flavones from the roots ofScutellaria baicalensis Georgi","volume":"48","author":"Wozniak","year":"2004","journal-title":"Food\/Nahrung"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"2371","DOI":"10.1271\/bbb.50698","article-title":"Antioxidative and Anti-Inflammatory Activities of Polyhydroxyflavonoids of Scutellaria baicalensisGEORGI","volume":"70","author":"Huang","year":"2006","journal-title":"Biosci. 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