{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T20:39:41Z","timestamp":1790887181261,"version":"4.1.0"},"reference-count":33,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2022,5,1]],"date-time":"2022-05-01T00:00:00Z","timestamp":1651363200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Gels"],"abstract":"<jats:p>In recent years, pH-sensitive hydrogels have been developed for the delivery of therapeutic agents to specific target sites that have a defined pH range. The use of pH-responsive polymers in hydrogels allows drug delivery to the desired pH range of the target organ. The primary aim is to increase the retention time of the drug in the small intestine by utilizing the swelling mechanism of the hydrogel at intestinal pH. In this study, polyethylene glycol (PEG) was used as a polymer to formulate a pH-sensitive hydrogel of Ezetimibe to deliver the drug to the small intestine where it inhibits the absorption of cholesterol. Design Expert software was applied to design and optimize the trial formulations in order to obtain an optimized formulation that has all the desired characteristics of the hydrogels. The PEG\/Acrylic Acid hydrogels showed the maximum swelling at pH 6.8, which is consistent with the pH of the small intestine (pH 6\u20137.4). The maximum entrapment efficiency of the hydrogels was 99%. The hydrogel released 80\u201390% of the drug within 24 h and followed first-order release kinetics, which showed that the release from the drug was sustained. Hence, the results showed that the choice of a suitable polymer can lead to the development of an efficient drug-loaded hydrogel that can deliver the drug at the specific pH of the target organ.<\/jats:p>","DOI":"10.3390\/gels8050281","type":"journal-article","created":{"date-parts":[[2022,5,1]],"date-time":"2022-05-01T06:23:08Z","timestamp":1651386188000},"page":"281","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":31,"title":["Synthesis of Chemically Cross-Linked pH-Sensitive Hydrogels for the Sustained Delivery of Ezetimibe"],"prefix":"10.3390","volume":"8","author":[{"given":"Rahima","family":"Khan","sequence":"first","affiliation":[{"name":"Faculty of Pharmacy, University of Central Punjab, Lahore 54000, Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1768-2979","authenticated-orcid":false,"given":"Muhammad","family":"Zaman","sequence":"additional","affiliation":[{"name":"Faculty of Pharmacy, University of Central Punjab, Lahore 54000, Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6342-284X","authenticated-orcid":false,"given":"Ahmad","family":"Salawi","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutics, College of Pharmacy, Jazan University, Jazan 45142, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5703-2730","authenticated-orcid":false,"given":"Mahtab Ahmad","family":"Khan","sequence":"additional","affiliation":[{"name":"Faculty of Pharmacy, University of Central Punjab, Lahore 54000, Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7122-9422","authenticated-orcid":false,"given":"Muhammad Omer","family":"Iqbal","sequence":"additional","affiliation":[{"name":"Shandong Provincial Key Laboratory of Glycoscience and Glycoengineering, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266005, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Romana","family":"Riaz","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutics, Faculty of Pharmacy, Bahauddin Zakariya University Multan, Multan 59300, Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Muhammad Masood","family":"Ahmed","sequence":"additional","affiliation":[{"name":"Faculty of Pharmaceutical Sciences, Times Institute, Multan 59300, Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4387-1351","authenticated-orcid":false,"given":"Muhammad Hammad","family":"Butt","sequence":"additional","affiliation":[{"name":"Faculty of Pharmacy, University of Central Punjab, Lahore 54000, Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Muhammad Nadeem","family":"Alvi","sequence":"additional","affiliation":[{"name":"Faculty of Pharmacy, University of Central Punjab, Lahore 54000, Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8385-6693","authenticated-orcid":false,"given":"Yosif","family":"Almoshari","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutics, College of Pharmacy, Jazan University, Jazan 45142, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0396-8653","authenticated-orcid":false,"given":"Meshal","family":"Alshamrani","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutics, College of Pharmacy, Jazan University, Jazan 45142, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,5,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Larra\u00f1eta, E., Stewart, S., Ervine, M., Al-Kasasbeh, R., and Donnelly, R.F. 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