Part I: Selection 1. Automated ssDNA SELEX Using Histidine Tagged Target Proteins Stefan Breuers and Günter Mayer 2. Discovery of Aptamers against Cell Surface Markers Using Ligand-Guided Selection Nicole Williams, Rutika Patel, and Prabodhika Mallikaratchy 3. Implementation of Emulsion PCR for Amplification of Click-Modified DNA during SELEX Moujab Choukeife, Anna Jonczyk, and Günter Mayer 4. Preparation of Chemically Modified DNA Library for SELEX via Incorporation of CLB-dUTP in Primer Extension Reaction Magda Puchala, Marta Radzińska, Joanna Guzdek, Agnieszka Sok-Grochowska, Aleksandra Adamowicz-Skrzypkowska, Pawel Pięta, Przemyslaw Jurek, and Monika Czarnecka 5. RNA Capture-SELEX on Streptavidin Magnetic Beads Leon Kraus and Beatrix Suess 6. The Bioinformatics of Aptamers: HT-SELEX Analysis with AptaSUITE Jan Hoinka and Teresa M. Przytycka 7. Improvement of Aptamers by High-Throughput Sequencing of Doped-SELEX Frédéric Ducongé Part II: Characterization 8. Analysis of Aptamer-Small Molecule Binding Interactions Using Isothermal Titration Calorimetry Sladjana Slavkovic and Philip E. Johnson 9. Determination of Aptamer Structure Using Circular Dichroism Spectroscopy Yannick Kerler, Stephan Sass, Carsten Hille, and Marcus M. Menger 10. Immobilization-Free Determination of Dissociation Constants Independent of Ligand Size Using MicroScale Thermophoresis Wiebke Sabrowski, Walter F.M. Stöcklein, and Marcus M. Menger 11. Label-Free Determination of the Kinetic Parameters of Protein-Aptamer Interaction by Surface Plasmon Resonance Nico Dreymann, Anja Möller, and Marcus M. Menger 12. Probing of Fluorogenic RNA Aptamers via Supramolecular Förster Resonance Energy Transfer with Universal Fluorescent Nucleobase Analog Christian Steinmetzger and Claudia Höbartner 13. Slow-Off-Rate-Modified Aptamer Labeling for Fluorescence Microscopy and DNA-PAINT Sebastian Strauss and Ralf Jungmann Part III: Application 14. Aptamer-Field-Effect Transistors for Small-Molecule Sensing in Complex Environments Nako Nakatsuka 15. Aptasensor for Impedimetric Detection of Lysozyme Ece Eksin, Huseyin Senturk, and Arzum Erdem 16. Biophysical Analysis of Small Molecule Binding to Viral RNA Structures