title: Strategies to Overcome Heparins' Low Oral Bioavailability.
abstract: 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's low oral bioavailability. Nevertheless, none have reached the market yet. Overall, this review aims to provide insights regarding the oral bioavailability of heparin.
authors.affiliation: Organic Chemistry and Pharmaceutical Laboratory, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Rua Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal. anarcneves92@gmail.com.
authors.forename: Ana Rita
authors.initials: AR
authors.lastname: Neves
authors.affiliation: Organic Chemistry and Pharmaceutical Laboratory, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Rua Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal. m_correiadasilva@ff.up.pt.|Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto, Rua dos Bragas 289, 4050-123 Porto, Portugal. m_correiadasilva@ff.up.pt.
authors.forename: Marta
authors.initials: M
authors.lastname: Correia-da-Silva
authors.affiliation: Organic Chemistry and Pharmaceutical Laboratory, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Rua Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal. esousa@ff.up.pt.|Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto, Rua dos Bragas 289, 4050-123 Porto, Portugal. esousa@ff.up.pt.
authors.forename: Emília
authors.initials: E
authors.lastname: Sousa
authors.affiliation: Organic Chemistry and Pharmaceutical Laboratory, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Rua Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal. madalena@ff.up.pt.|Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto, Rua dos Bragas 289, 4050-123 Porto, Portugal. madalena@ff.up.pt.
authors.forename: Madalena
authors.initials: M
authors.lastname: Pinto
keywords: anticoagulant; heparin; oral bioavailability