Fig. 1. Schematic of the tilted slit-groove interferometer: (a)top view,(b)excitation scheme.
Melentiev and his colleagues have realized a plasmonic interferometer formed by a nanoslit and a nanogroove in a single-crystal gold film. The possibility of measuring laser pulses of ultimately short durations, corresponding to two periods of a light wave (6 fs pulse duration), has been demonstrated using this interferometer.
Guner and his colleagues demonstrate a surface plasmon resonance imaging platform integrated with a smartphone to be used in the field with high-throughput bio-detection. Inexpensive and disposable SPR substrates are produced by metal coating of commercial Blu-ray discs. A compact imaging apparatus is fabricated using a 3D printer which allows taking SPR measurements from more than 20.000 individual pixels. Real-time bulk refractive index change measurements yield noise equivalent refractive index changes as low as4.12 × 10−5RIU which is comparable with the detection performance of commercial instruments. As a demonstration of a biological assay, they have shown capture of mouse IgG antibodies by immobilized layer of rabbit anti-mouse (RAM) IgG antibody with nanomolar level limit of detection. Their approach in miniaturization of SPR biosensing in a cost-effective manner could enable realization of portable SPR measurement systems and kits for point-of-care applications.