Frieder Scheller and the Short History of Biosensors -- Protein Electrodes with Direct Electrochemical Communication -- Protein Engineering and Electrochemical Biosensors -- Artificial Receptors -- New Trends in Immunoassays -- Electrochemical Biochips for Protein Analysis -- Impedance Spectroscopy and Biosensing -- Amplified Transduction of Biomolecular Interactions Based on the Use of Nanomaterials -- Photoelectrochemical and Optical Applications of Semiconductor Quantum Dots for Bioanalysis -- Microsystems Technology and Biosensing -- Development of Microbial Sensors and Their Application -- Strategies for Label-Free Optical Detection -- DNA Microarrays -- Scanning Electrochemical Microscopy (SECM) as a Tool in Biosensor Research.