Biochemical sensing exploiting plasmonic sensors based on gold nanogratings and polymer optical fibers

Abstract

In this work, we present a novel biochemical sensing approach based on a plasmonic sensor chip, combined with a specific receptor, excited and interrogated via a custom 3D-printed holder through a transmission-based experimental setup, exploiting polymer optical fibers. The setup is designed to measure a disposable plasmonic chip based on a gold nanograting fabricated on a polymethylmethacrylate substrate. The examined sensor configurations here presented are simulated, realized, and experimentally tested. More specifically, first, a numerical analysis is carried out by changing several sensor parameters, then an experimental optical characterization of different sensor configurations is reported. Finally, to test the biosensing capabilities of the proposed method, as a proof of concept, we deposit on the best sensor configuration a biomimetic receptor specific for bovine serum albumin detection. The experimental results demonstrate that the proposed sensor shows an ultra-low limit of detection, equal to about 37 pmol/L.

A Nanoplasmonic-Based Biosensing Approach for Wide-Range and Highly Sensitive Detection of Chemicals

“…In order to exploit the maximum potential of this type of plastic slab waveguide chip and take full advantage of its dimension (10 mm × 10 mm × 0.5 mm), fully compliant to the modern holder of electron beam lithography (EBL) systems (e.g., Zeiss Supra v35-Raith Elphy Quantum system), we conceived and tested a plasmonic sensor based on a gold nanograting (GNG) fabricated on the top of this PMMA chip [39]. In particular, as proof of concept, we functionalized the nano groove surface with a synthetic receptor specific for the bovine serum albumin (BSA), and we tested its biosensing capabilities by using an experimental setup described in [39]. In particular, in [39] the PMMA substrate has been considered a transparent substrate instead of a waveguide.…”

“…In particular, as proof of concept, we functionalized the nano groove surface with a synthetic receptor specific for the bovine serum albumin (BSA), and we tested its biosensing capabilities by using an experimental setup described in [39]. In particular, in [39] the PMMA substrate has been considered a transparent substrate instead of a waveguide. Moreover, a similar nanostructure has also demonstrated an excellent solution to realize Surface-enhanced Raman scattering (SERS) active substrates [40].…”

“…Finally, we also carried out a comparative analysis in terms of limit of detection (LOD) with an SPR probe based on POF and functionalized with the same receptor. In this work, exploiting the proposed setup, we changed the angle of the incident light with respect to [39] in the plasmonic phenomena obtaining different performances. In particular, we used the best configuration obtained in [39] in terms of geometric parameters of the GNG.…”

“…In this work, exploiting the proposed setup, we changed the angle of the incident light with respect to [39] in the plasmonic phenomena obtaining different performances. In particular, we used the best configuration obtained in [39] in terms of geometric parameters of the GNG. We do not present any parametric optimization of the device in numerical and experimental results, as reported in [39], even if the geometric parameter variation influences the performances.…”

“…In particular, we used the best configuration obtained in [39] in terms of geometric parameters of the GNG. We do not present any parametric optimization of the device in numerical and experimental results, as reported in [39], even if the geometric parameter variation influences the performances. In fact, this work aims to compare the performances of the proposed setup with those proposed in [39].…”