Highly sensitive detection of biomolecules with the magneto-optic surface-plasmon-resonance sensor

TLDR

The MOSPR sensor combines magneto‑optic activity of magnetic materials with surface‑plasmon resonance, producing a sharp enhancement of magneto‑optic effects that depends on the surrounding medium’s optical properties and enabling biosensing. The study presents the characteristics of this novel MOSPR sensor and its application for detecting biomolecules. Experimental tests demonstrate a three‑fold improvement in limit of detection for refractive index changes and biomolecule adsorption compared with standard sensors, with potential to reach a ten‑fold gain through further optimization.

Abstract

The characteristics of a novel magneto-optic surface-plasmon-resonance (MOSPR) sensor and its use for the detection of biomolecules are presented. This physical transduction principle is based on the combination of the magneto-optic activity of magnetic materials and a surface-plasmon resonance of metallic layers. Such a combination can produce a sharp enhancement of the magneto-optic effects that strongly depends on the optical properties of the surrounding medium, allowing its use for biosensing applications. Experimental characterizations of the MOSPR sensor have shown an increase in the limit of detection by a factor of 3 in changes of refractive index and in the adsorption of biomolecules compared with standard sensors. Optimization of the metallic layers and the experimental setup could result in an improvement of the limit of detection by as much as 1 order of magnitude.