(Nano)plasmonic technologies are the landmark in optical label-free biosensors. We have been pioneers in the development of compact and highly sensitive Surface Plasmon Resonance (SPR) biosensor devices, which have been applied to a myriad of clinical and environmental applications with relevant sensitivity. We also explore the design of novel plasmonic nanostructures for high-performance miniaturized Nanoplasmonic sensors platforms with multiplexed capabilities. Our research comprises the whole process, from the initial design of the improved nanostructures and their optimized fabrication, to the final integration and implementation in portable user-friendly devices for routine analysis.