In addition to their biological functions, nucleic acids can fold into defined structures that are endowed with precise recognition properties, which have been exploited as diagnostic tools, drug molecules, biosensors and nanostructures. Their properties have been enhanced by attaching other groups, such as fluorophores, small molecules and enzymes, which facilitate their detection, stabilise them against degradation and promote their enzymic and recognition properties. These DNA conjugates are excellent diagnostic tools for the identification and treatment of diseases, as well as for forensic applications. Written by leaders in the field, this volume describes the preparation, properties and applications of these DNA-conjugates. Several have been used as sensors (aptamers, riboswitches and nanostructures) based on the ability of nucleic acids to adopt specific structures in the presence of ligands, whilst others contain reporter groups such as proteins or fluorophores for nucleic acid detection or for use in single molecule studies. This book will interest researchers in areas related to analytical chemistry, chemical biology, medicinal chemistry, molecular pharmacology, and structural and molecular biology.