This book reviews the development, characterization and applications of aptamers in different areas of biotechnology ranging from therapeutics to diagnostics and protein purification. Hailed as chemical antibodies, these single-stranded nucleic acid receptors were predicted to supersede antibodies in traditional assays, such as ELISA, within a short time. While this has yet to happen, readers will find in this book a deep insight into the progress of aptamer technology and a critical discussion about the limitations that need to be overcome in order to find wider acceptance and use outside of the still relatively small aptamer-community. This book covers all aspects of aptamer generation and application for