ABSTRACT
Surface plasmon resonance (SPR)-based sensors have seen tremendous developments during the past decade, and some of these sensors are becoming a mature technology now, although improvements in their sensitivity and detection limit are ongoing. Together with the recent investigations in localized SPR (LSPR) phenomena, extraordinary optical transmission through nanoapertures in metals, and surface-enhanced spectroscopies, drastic developments are expected to revolutionize the field of optical sensing. Sensitivity enhancement techniques based on SPR phenomena are reviewed, focusing both on physical transduction mechanisms and system performance. It is shown that in the majority of cases, sensitivity enhancement is associated with the enhancement of the electromagnetic (EM) field overlap integral describing the EM interaction energy within the analyte.
