Biomedical applications of hydrogels in the form of nano- and microparticles

Abstract

Hydrogels are hydrophilic three-dimensional networks of polymeric chains randomly crosslinked by physical or chemical bonds that are able to adsorb large amounts of water. They can be shaped into different physical conformations, such as films, tablets, sponges, fibers or particles in the range of nano and micro scale. This last conformation that includes numerous multi-particulated forms -from particles without any form to spheres- has directly been used in different biomedical applications or as a part of another conformation. Normally, a particulate form of a hydrogel is used when the biomedical application aims at delivering, immobilizing, and/or purifying a biomolecule or when a biological fluid adsorption capacity is necessary. Here, the role of different hydrogels in the form of particles ?with different polymer nature, composition, polymerization, crosslinking and chemical modification- will be discussed. Special attention will be given to the specific polymer characteristics that bring a desired property to the final product in the areas of drug delivery, gene carriers, tissue engineering and scaffolds, biosensors, cosmetics and diagnostic imaging.