Biosensing based on plasmonic devices

Biosensing consists of the detection of biological agents based on the principles that govern living systems. Regarding the increasing complexity of the problems that humanity faces, it is essential to have accurate biosensors capable of offering as much information as possible in a fast, cheap, and reliable way. This chapter presents the fundamental concepts of using plasmonics as a mechanism for biosensing. Thus, the concepts of surface plasmons (SPs) are described together with the physical interpretation of both localized surface plasmons (LSPs) and surface plasmon polaritons (SPPs). We also introduce all the relevant plasmonic parameters in sensing and describe the fundamental operation of Kretschmann and Otto configurations, as well as grating systems. Finally, we discuss the potential of chirality in biosensing describing LSPR and SPP-based chiral platforms in the context of chiral sensing. We close the chapter by analyzing their performance and revising some of the most representative advances in the matter, giving examples of state-of-the-art chiral plasmonic biosensors.