Beads as Drug Carriers

Chapter
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Abstract

Beads are often used as drug carriers in passive, as well as active drug targeting, making this a highly relevant topic in today’s research. Major general topics covered in the first part of this chapter include controlled drug release, gels in drug-delivery systems, dual- drug-loaded beads, and drug release from the beads. Throughout, issues such as methods of drug incorporation, bead properties, extent and nature of crosslinking and the physicochemical properties of the drug, interactions between the drug and the matrix material, concentration of the matrix material and release environment (e.g., the presence of enzymes), are discussed. Described beads include albumin beads, alginate beads, alginate beads reinforced with chitosan, calcium -alginate/PNIPAAM beads, different chitosan beads (i.e., chitosan–tripolyphosphate beads, chitosan microspheres in treating rheumatoid arthritis, carboxymethyl chitosan beads), gelatin beads and those crosslinked with dextran, modified starch microspheres, dextran beads, gellan beads, guar beads, pectin beads for colon-specific drug delivery, pectin–chitosan beads, and modified poly(vinyl alcohol) microspheres. The chapter also summarizes information on achieving controlled production of the beads, such as preparation of biodegradable hydrogels based on polyesters, hydrogels with degradable crosslinking agents and those crosslinked with small molecules, azo reagents or albumin, and hydrogels with biodegradable pendant chains. The chapter finishes with a description of the more unique beads, such as those with floating ability and those made from xyloglucan.

Keywords

Drug Release Lower Critical Solution Temperature Alginate Bead Entrapment Efficiency Chitosan Microsphere 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
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© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  1. 1.Institute of Biochemistry, Food Science and Human Nutrition, The Robert H. Smith Faculty of Agriculture, Food and EnvironmentThe Hebrew University of JerusalemRehovotIsrael

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