Microfluidic Plasmonic Biosensor for Breast Cancer Antigen Detection

Abstract

Biosensors based on surface plasmon resonance (SPR), operating with the Kretschmann conventional arrangement, have been employed for biomolecular detection of tumor markers. However, the traditional SPR configuration presents some experimental inconveniences that are overcome by using plasmonic substrates based on nanohole arrays manufactured in metallic films. This SPR configuration exhibits the extraordinary optical transmission (EOT) phenomenon, which is explored in the monitoring of binding events that occur on the metal surface. In this work, we proposed a plasmon biosensor based on nanohole arrays built on gold film operating in collinear transmission mode by using spectral investigation for signal transduction. The SPR substrate was coupled to a microfluidic system and showed good sensitivity and linearity. A concentration of 30 ng mL −1 of human epidermal receptor protein-2 (HER2) antigen (associated with breast cancer) was detected using the integrated device; this showed its great potential to be used in tumor diagnosis.

Recent Progress in Surface Plasmon Resonance Biosensors  (2016 to Mid-2018)

“…To enhance the SPR signal, a sandwich biosensor may be used [3]. The first antibody captures the marker, while the marker captures the second antibody.…”

“…Usually, a chromium-or alternatively, titanium-under-layer is used. Only a few papers report other solutions, such as a gold-covered glass fiber[5], a gold nanohole array[3] or a prism covered with gold and graphene[41]. Frequently, a gold chip surface is covered by a polymer with holes, creating an array of free gold measuring points.A crucial part of a biosensor is the receptor.…”

Plasmonic Sensors for Disease Detection - A Review

“…As the molecules are immobilized on the surface, the refractive index on the metal-dielectric interface increases, leading to a redshift. Compared to the AB1 immobilization step, a shift of 1.2 nm was observed when the HER2 [91][92][93] antigen (concentration 30 ng mL −1 ) was immobilized. An extra redshift of 1.3 nm was observed when AB2 was linked to the AB1/HER2 layer; this resulted in a 2.5-nm total band displacement.…”

Surface Plasmon Resonance (SPR) to Magneto-Optic SPR

“…Currently, SPR sensors have reached their detection limit [7]. For details on plasmonics and SPR, and technical reviews, the readers are referred to [8][9][10][11][12][13].…”