Fano Resonance-Based Blood Plasma Monitoring and Sensing using Plasmonic Nanomatryoshka

Abstract

The fast label-free detection of specific antibodies and their concentration in blood plasma is useful for many applications, e.g., in Covid-19 patients. The change in biophysical properties like the refractive index of blood plasma due to the production of antibodies during infection may be very helpful in estimating the level and intensity of infection and subsequent treatment based on blood plasma therapy. In this article, Fano resonance-based refractive index sensor using plasmonic nanomatryoshka is proposed for blood plasma sensing. The interaction between hybridized modes (bright and dark modes) in optimized nanomatryoshka leads to Fano resonance, which by virtue of steeper dispersion can confine the light more efficiently compared with Lorentzian resonance. We propose the excitation of Fano resonances in sub 100-nm size nanomatryoshka based on newly emerging plasmonic materials ZrN and HfN, and one of the most widely used conventional plasmonic material, Au. Fano resonance-based plasmonic sensors leads to sensitivity = 188.5 nm/RIU, 242.5 nm/RIU, and 244.9 nm/RIU for Au, ZrN, and HfN, respectively. The corresponding figure of merit (nm/RIU) is ~ 3.5 × 10 3 , 3.1 × 10 3 , and 2.8 × 10 3 for Au, ZrN, and HfN, respectively. Present theoretical analysis shows that refractive index sensors with high sensitivity and figure of merit are feasible using Fano modes of plasmonic nanomatryoshka.

Theoretical Studies and Simulation of Gold–Silica–Gold Multilayer “Fanoshells” for Sensing Applications

“…The last column in Table shows that there is a significant improvement in S λ when the Au core is replaced with a Ag core. The use of other materials such as graphene or other noble metals, , reduction of the core size, or increasing the overall size of the MNS geometry , can enhance these parameters even further.…”

“…2,4−6 However, the term "Fano resonances" has also been used to describe the plasmon resonances formed via the plasmon hybridization of dipolar solid sphere and nanoshell plasmons in multilayer nanoshells (MNSs). 1,7 Here, we will adopt both definitions, the latter being more relevant when there is no geometrical symmetry breaking, 1,3,7 while the former is more relevant to symmetry-broken conventional nanoshells (CNSs) 2,8 and MNSs. 1,6,9 In these geometries, the Fano effect has been shown to occur via dipole−quadrupole and higher order couplings, which cause the multipolar mode to become dipole-active, i.e., the LSPR of the dark, multipolar mode becomes enhanced and visible in the spectra, while the LSPR of the bright, dipolar mode becomes less radiant or suppressed.…”

“…The term “Fanoshells” was first used in ref to refer to core–shell nanostructures capable of supporting localized surface plasmon resonances (LSPRs) with Fano-like lineshapesLSPRs with a distortion in their spectral lineshapes that results in an LSPR shift. − These resonances, known as Fano resonances, are formed as a result of interference between radiant, broad-band, dipolar modes and optically dark, narrow-band, multipolar modes such as quadrupole modes. ,− However, the term “Fano resonances” has also been used to describe the plasmon resonances formed via the plasmon hybridization of dipolar solid sphere and nanoshell plasmons in multilayer nanoshells (MNSs). , Here, we will adopt both definitions, the latter being more relevant when there is no geometrical symmetry breaking, ,, while the former is more relevant to symmetry-broken conventional nanoshells (CNSs) , and MNSs. ,, In these geometries, the Fano effect has been shown to occur via dipole–quadrupole and higher order couplings, which cause the multipolar mode to become dipole-active, i.e., the LSPR of the dark, multipolar mode becomes enhanced and visible in the spectra, while the LSPR of the bright, dipolar mode becomes less radiant or suppressed. ,, Mode enhancement and suppression can be revealed by calculating the dipole polarizability of the Fanoshell , or the complex amplitude of the radiant, dipolar mode , to show that such dipole-active modes are only present in the absorption and scattering spectra of symmetry-broken CNSs ,, and MNSs. , …”

Independently tunable refractive index sensor based on metal-insulator-metal waveguide with key-shaped resonator and application in human blood plasma detection

“…Normally, the concentration of healthy human plasma is 1.32459 g l −1 , but diseases such as hyperglycemia and hyperlipidemia may cause plasma concentrations to fall outside the normal range. The refractive index of blood plasma can be noted as [41]:…”

Geometrical parameters affect on local electric field enhancement of bimetallic three-layered nanotubes by using quasi-static theory

“…Silver-dielectric-silver three-layered nanoshell shows the sensitivity could be increased by reducing the silver core [19]. Pathania et-al have presented Fano resonance-based refractive index sensor using plasmonic nanomatryoshka for blood plasma sensing [20]. Zhu etal have theoretically studied local electric field enhancement in a long cylindrical Au nanohole with Pt coating based on quasi-static model, the local field factor in Pt shell is sensitive to the Pt thickness and local dielectric environment [21].…”