Hydrogels in Biology and Medicine: From Molecular Principles to Bionanotechnology

• Published in: Advanced materials (Weinheim) Vol. 18; no. 11; pp. 1345 - 1360
• Main Authors: Peppas, N. A., Hilt, J. Z., Khademhosseini, A., Langer, R.
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 06-06-2006; WILEY‐VCH Verlag
• Subjects: Biomedical materials; Biosensors; Cells; Drug delivery; Hydrogels; Microfluidic systems; Polymeric materials; Tissue engineering
• ISSN: 0935-9648; 1521-4095
• DOI: 10.1002/adma.200501612

Hydrophilic polymers are the center of research emphasis in nanotechnology because of their perceived “intelligence”. They can be used as thin films, scaffolds, or nanoparticles in a wide range of biomedical and biological applications. Here we highlight recent developments in engineering uncrosslinked and crosslinked hydrophilic polymers for these applications. Natural, biohybrid, and synthetic hydrophilic polymers and hydrogels are analyzed and their thermodynamic responses are discussed. In addition, examples of the use of hydrogels for various therapeutic applications are given. We show how such systems' intelligent behavior can be used in sensors, microarrays, and imaging. Finally, we outline challenges for the future in integrating hydrogels into biomedical applications.
The science and theory of hydrogels as well as their biomedical applications are reviewed. Their thermodynamic properties, theory, and types of hydrogels are discussed, and examples of their use for therapeutic and diagnostics applications are given. Future directions and challenges in the synthesis and use of hydrogels are also outlined. The figure shows the formation of a fluorescent hydrogel gradient using a microfluidic system (inlet channels diameter: 80 μm).