title: Hydrogels in a historical perspective: from simple networks to smart materials.
abstract: Over the past decades, significant progress has been made in the field of hydrogels as functional biomaterials. Biomedical application of hydrogels was initially hindered by the toxicity of crosslinking agents and limitations of hydrogel formation under physiological conditions. Emerging knowledge in polymer chemistry and increased understanding of biological processes resulted in the design of versatile materials and minimally invasive therapies. Hydrogel matrices comprise a wide range of natural and synthetic polymers held together by a variety of physical or chemical crosslinks. With their capacity to embed pharmaceutical agents in their hydrophilic crosslinked network, hydrogels form promising materials for controlled drug release and tissue engineering. Despite all their beneficial properties, there are still several challenges to overcome for clinical translation. In this review, we provide a historical overview of the developments in hydrogel research from simple networks to smart materials.
authors.affiliation: Department of Pharmaceutics, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands.
authors.forename: Sytze J
authors.initials: SJ
authors.lastname: Buwalda
authors.affiliation: Department of Pharmaceutics, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands.
authors.forename: Kristel W M
authors.initials: KW
authors.lastname: Boere
authors.affiliation: Department of Developmental BioEngineering, Faculty of Science and Technology, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, The Netherlands.
authors.forename: Pieter J
authors.initials: PJ
authors.lastname: Dijkstra
authors.affiliation: Department of Polymer Chemistry and Biomaterials, Faculty of Science and Technology, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, The Netherlands; Biomedical Polymers Laboratory, Department of Polymer Science and Engineering, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, PR China; Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application, Department of Polymer Science and Engineering, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, PR China.
authors.forename: Jan
authors.initials: J
authors.lastname: Feijen
authors.affiliation: Department of Pharmaceutics, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands.
authors.forename: Tina
authors.initials: T
authors.lastname: Vermonden
authors.affiliation: Department of Pharmaceutics, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands.
authors.forename: Wim E
authors.initials: WE
authors.lastname: Hennink
mesh_terms: D001672:Biocompatible Materials / Q000266:history; D003692:Delayed-Action Preparations / Q000266:history; D004337:Drug Carriers / Q000737:chemistry / Q000266:history; D049673:History, 20th Century; D049674:History, 21st Century; D006801:Humans; D020100:Hydrogels / Q000737:chemistry / Q000266:history; D011092:Polyethylene Glycols; D011102:Polyhydroxyethyl Methacrylate
chemical_list: D001672:Biocompatible Materials; D003692:Delayed-Action Preparations; D004337:Drug Carriers; D020100:Hydrogels; D011102:Polyhydroxyethyl Methacrylate; D011092:Polyethylene Glycols
keywords: Biomaterials; Controlled release; Drug delivery; Historical overview; Hydrogels; Polymer science