{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,3]],"date-time":"2026-02-03T21:12:25Z","timestamp":1770153145317,"version":"3.49.0"},"reference-count":99,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2016,6,29]],"date-time":"2016-06-29T00:00:00Z","timestamp":1467158400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"ERDF, COMPETE, and FCT","award":["UID\/Multi\/04423\/2013"],"award-info":[{"award-number":["UID\/Multi\/04423\/2013"]}]},{"name":"ERDF, COMPETE, and FCT","award":["INNOVMAR\u2014Innovation and Sustainability in the Management and Exploitation of Marine Resources, reference NORTE-01-0145-FEDER-000035, Research Line NOVELMAR."],"award-info":[{"award-number":["INNOVMAR\u2014Innovation and Sustainability in the Management and Exploitation of Marine Resources, reference NORTE-01-0145-FEDER-000035, Research Line NOVELMAR."]}]},{"name":"ERDF, COMPETE, and FCT","award":["PTDC\/MAR-BIO\/4694\/2014 and PTDC\/AAG-TEC\/0739\/2014"],"award-info":[{"award-number":["PTDC\/MAR-BIO\/4694\/2014 and PTDC\/AAG-TEC\/0739\/2014"]}]},{"name":"ERDF, COMPETE, and FCT","award":["PTDC\/MAR-BIO\/4694\/2014"],"award-info":[{"award-number":["PTDC\/MAR-BIO\/4694\/2014"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pharmaceuticals"],"abstract":"<jats:p>Even after a century, heparin is still the most effective anticoagulant available with few side effects. The poor oral absorption of heparins triggered the search for strategies to achieve oral bioavailability since this route has evident advantages over parenteral administration. Several approaches emerged, such as conjugation of heparins with bile acids and lipids, formulation with penetration enhancers, and encapsulation of heparins in micro and nanoparticles. Some of these strategies appear to have potential as good delivery systems to overcome heparin\u2019s low oral bioavailability. Nevertheless, none have reached the market yet. Overall, this review aims to provide insights regarding the oral bioavailability of heparin.<\/jats:p>","DOI":"10.3390\/ph9030037","type":"journal-article","created":{"date-parts":[[2016,6,29]],"date-time":"2016-06-29T17:03:22Z","timestamp":1467219802000},"page":"37","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":26,"title":["Strategies to Overcome Heparins\u2019 Low Oral Bioavailability"],"prefix":"10.3390","volume":"9","author":[{"given":"Ana","family":"Neves","sequence":"first","affiliation":[{"name":"Organic Chemistry and Pharmaceutical Laboratory, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Rua Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4150-8532","authenticated-orcid":false,"given":"Marta","family":"Correia-da-Silva","sequence":"additional","affiliation":[{"name":"Organic Chemistry and Pharmaceutical Laboratory, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Rua Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal"},{"name":"Interdisciplinary Centre of Marine and Environmental Research (CIIMAR\/CIMAR), University of Porto, Rua dos Bragas 289, 4050-123 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5397-4672","authenticated-orcid":false,"given":"Em\u00edlia","family":"Sousa","sequence":"additional","affiliation":[{"name":"Organic Chemistry and Pharmaceutical Laboratory, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Rua Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal"},{"name":"Interdisciplinary Centre of Marine and Environmental Research (CIIMAR\/CIMAR), University of Porto, Rua dos Bragas 289, 4050-123 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4676-1409","authenticated-orcid":false,"given":"Madalena","family":"Pinto","sequence":"additional","affiliation":[{"name":"Organic Chemistry and Pharmaceutical Laboratory, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Rua Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal"},{"name":"Interdisciplinary Centre of Marine and Environmental Research (CIIMAR\/CIMAR), University of Porto, Rua dos Bragas 289, 4050-123 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2016,6,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"757","DOI":"10.1111\/j.1365-2141.2008.07119.x","article-title":"The story of the discovery of heparin and warfarin","volume":"141","author":"Wardrop","year":"2008","journal-title":"Br. 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