Raffaele Velotta has worked on laser application for many years (molecular alignment, high-order harmonic generation and attosecond pulse generation being the main topics). In 2009 he moved to applications of the knowledge gained in optics to biosensing; in particular, he developed a surface functionalization strategy (Photochemical Immobilization Technique, PIT) capable to tether antibodies upright on gold (and silver). This has been lending itself to biosensing carried out by many transducers like the electrochemical ones, but also those based on quartz-crystal microbalances (QCM), surface plasmon resonance (SPR), localized SPR in nanoparticles and metal-enhanced fluorescence, all of them sharing the presence of gold surfaces. PIT makes selective against any analyte for which Ab exists.