Fourier Transform Surface Plasmon Resonance (FTSPR) with Gyromagnetic Plasmonic Nanorods

Abstract

An unprecedented active and dynamic sensing platform based on a LSPR configuration that is modulated by using an external magnetic field is reported. Electrochemically synthesized Au/Fe/Au nanorods exhibited plasmonically active behavior through plasmonic coupling, and the middle ferromagnetic Fe block responded to a magnetic impetus, allowing the nanorods to be modulated. The shear force variation induced by the specific binding events between antigens and antibodies on the nanorod surface is used to enhance the sensitivity of detection of antigens in the plasmonics-based sensor application. As a proof-of-concept, influenza A virus (HA1) was used as a target protein. The limit of detection was enhanced by two orders of magnitude compared to that of traditional LSPR sensing.

Responsive Plasmonic Nanomaterials for Advanced Cancer Diagnostics

“…The LSPR intensity and the perceived color of Au nanorods in a colloidal solution can be quickly tuned by applying a magnetic field. A few advanced techniques enable direct colloidal synthesis of magnetic-plasmonic hybrid nanostructures, including Fe 3 O 4 @Au core/shell nanospheres (Figure 2A) (Li et al, 2020a), Fe 3 O 4 /Au nanorods ( Figure 2B) (Li et al, 2020b), Fe 3 O 4 /Ag nanorods (Li et al, 2020e), Au/Ni/Au ( Figure 2C) (Jung et al, 2018a), Au/Fe/Au multiblock nanorods (Jung et al, 2018b), and Au dimer on magnetic nanoplate hybrid structure ( Figure 2D) (Feng et al, 2019). One advantage of magnetic orientational control is the selective excitation of the two modes of Au nanorods.…”

Recent advances in gold nanoparticles for biomedical applications: from hybrid structures to multi-functionality

“…138 Combining magnetic features with plasmonics can be achieved by making the multi-layered nanoparticles comprising plasmonic metals with ferromagnetic materials (Fig. 7b and f) 23,[139][140][141] or by alloying them (Fig. 7d, 142 from upper-left to lower-right in the framework in Fig.…”

“…7c. 140 On the other hand, if the probe is protected from any surface interaction (i.e. no change in S), then viscosity becomes a sole variable affecting f and can be measured by tracking f. This is particularly interesting when the nanoprobes are in the complex fluids containing a mixture of multiple phases.…”

“…(b) HR-TEM image of a Au/Fe/Au nanorod and its corresponding elemental false-colour mapping images. (c) FFT plots of the extinction signals of the Au/Fe/Au nanoprobes under a magnetic field rotating at 3.33 Hz (black: bare probe, red: probe with antibody, blue: probe with antibody-antigen reaction) 140. (d) TEM image of the 2-turn Au-Fe nanohelix with ca.…”

Multisegmented Metallic Nanorods: Sub‐10 nm Growth, Nanoscale Manipulation, and Subwavelength Imaging

“…Through simultaneous manipulation and imaging, desired movement and timely visualization of MS‐M‐NRs can be readily achieved, which is of great importance to device fabrication, multiplex sensing, biomedical application, and so on. Several techniques capable of simultaneous manipulation and imaging of MS‐M‐NRs have been developed . Park et al have demonstrated simultaneous magnetic orientation and plasmonic response of Au‐Ni‐Au nanorods in heavy water by combination of rotating magnetic field and UV–vis spectroscopy ( Figure a) .…”