Plasmonic Sensing of Oncoproteins without Resonance Shift Using 3D Periodic Nanocavity in Nanocup Arrays

Abstract

of surface plasmons with an incoherent light source and the detection with a portable spectrometer; however, the sensitivity of these devices is an order of magnitude lower than conventional SPR sensors. [7] Here, we report a new nanoplasmonic resonance sensor design that shows a unique interactive plasmonic-photonic resonance effect: only resonance peak intensity variation, not a plasmon resonance wavelength shift, is observed in the far field as a function of the optical refractive index (RI) on the superstrate when a periodic plasmonic nanostructure and a multilayer nanocavity are combined. Multilayer plasmonic structures have been investigated for on-chip photonic devices, such as multilayered plasmonic waveguides. [8] Metal-insulator-metal (MIM) surface plasmon waveguides have been studied for refractometric detection. [9] In addition, the localized surface plasmon resonance (LSPR) effect has been used with multilayered geometries to increase light-induced catalytic activity of materials such as palladium. [10] The study of dielectric films and MIM structures combined with an EOT substrate has been reported previously. [11] However, these prior works focused on surface enhanced Raman spectroscopy applications or on the plasmon resonance peak shift of nanohole arrays and the sensitivity of these structures to superstrate RI changes was lower than conventional EOT devices.The new hybrid nanoplasmonic-nanocavity sensor that we utilize here is based on a 3D plasmonic nanocup resonator structure, which consists of a nanostructured polymer substrate with a deposited gold (Au) layer. [12] To form a nanocavity A sensor design and sensing method based on plasmonic-photonic interactions that occur when a nanocavity array is embedded in a 3D tapered nanocup plasmonic substrate are reported. This device enables highly sensitive detection of refractive index changes based on changes to the transmission peak intensity without shift in the resonance wavelength. Unlike conventional plasmonic sensors, there is a consistent and selective change in the transmission intensity at the resonance peak wavelength with no spectral shift. In addition, there are wavelength ranges that show no intensity change, which can be used as reference regions. The fabrication and characterization of the plasmonic nanocavity sensor are described and also advanced biosensing is demonstrated. Simulations are carried out to better understand the plasmon-photonic coupling mechanism. This nanocavity plasmonic sensor design has a limit of detection of 1 ng mL −1 (5 × 10 −12 m) for the cancer biomarker carcinoembryonic antigen (CEA), which is a significant improvement over current surface plasmon resonance systems, and a dynamic range that is clinically relevant for human CEA levels.

Multifunctional Skin‐Inspired Flexible Sensor Systems for Wearable Electronics

“…Another category of optical sensors is plasmon‐enhanced optical sensing, which is generally built from judiciously tailored plasmonic nanostructures, rendering the enhancement or modulation of optical signals possible, such as spectral‐shifts based plasmonic sensors, plasmon‐enhanced fluorescence sensors, and surface‐enhanced Raman scattering (SERS) sensors, etc . Particularly, SERS has attracted intensive research attentions due to its capability to provide fingerprint information of analytes with narrow spectral peaks .…”

Plasmonic Biosensors for Single-Molecule Biomedical Analysis

“…The utilization of metallic surfaces with EOT implies that surface plasmons could be excited with an incoherent source of light. The spectral analysis of the transmission peaks generated by changes in the local refractive index can be monitored through a portable spectrometer using various plasmonic modes [ 56 ]. In comparison to other SPR arrangements, nanohole arrays enable several scattering orders that rely on the shape, size, periodicity, dielectric properties and composition of the materials [ 55 ].…”

Skin-Patchable Electrodes for Biosensor Applications: A Review

“…The flexible and transparent polymer film showing surface plasmon resonance (SPR) effect was effectively used to detect various chemicals. Ameen et al 154 devised a sensor and sensing method based on plasmonic-photonic interactions that occurred when a nanocavity array was incorporated in a 3D tapered nanocup plasmonic substrate. Thus, prepared sensor allowed very sensitive sensing of changes in refractive index with respect to changes in transmission peak intensity without any shift in the resonance peak wavelength.…”