Bovine Serum Albumin Protein Detection by a Removable SPR Chip Combined with a Specific MIP Receptor

Abstract

Nowadays, the development of simple, fast, and low-cost selective sensors to detect substances of interest is of great importance in several application fields. Among this kind of sensors, those based on surface plasmon resonance (SPR) represent a promising category, since they are highly sensitive, versatile, and label-free. In this work, an SPR probe, based on a poly(methyl methacrylate) (PMMA) slab waveguide covered by a gold nanofilm, combined with a specific molecularly imprinted polymer (MIP) receptor for bovine serum albumin (BSA) protein, has been realized and experimentally characterized. The obtained experimental results have shown a limit of detection (LOD) equal to about 8.5 × 10−9 M. This value is smaller than the one achieved by another SPR probe, based on a D-shaped plastic optical fiber (POF), functionalized with the same MIP receptor; more specifically, the obtained LOD was reduced by about three orders of magnitude with respect to the POF configuration. Moreover, concerning the D-shaped POF configuration, no manufacturing process is present in the proposed sensor configuration. In addition, fibers are used only to connect the simple sensor chip with a light source and a detector, promoting a bio-chemical sensing approach based on disposable, low-cost, and removable chips.

On the Effect of Soft Molecularly Imprinted Nanoparticles Receptors Combined to Nanoplasmonic Probes for Biomedical Applications

“…The equipment consists of a white light source (HL-2000-LL, manufactured by Ocean Optics, Dunedin, FL, United States, with an emission range from 360 to 1700 nm), a spectrometer with a detection range from 350 to 1,023 nm (FLAME-S-VIS-NIR-ES, manufactured by Ocean Optics, Dunedin, FL, United States), two POF patches, and an aluminium holder realized by our group to monitor this kind of plasmonic chip (Cennamo et al, 2017). As shown in Figure 3, all these components are connected similarly to the PMMA plasmonic sensors reported in (Cennamo et al, 2017;Arcadio et al, 2021c). Figure 3 shows the light propagation path through the setup, with the light propagated from the source to the first plastic optical fiber (POF) patch (1 mm total diameter).…”

“…We expect information on the effects of the MIP formats can be devised by the comparison between nano-plasmonic probes based on optimized nanostructured slabs (Arcadio et al, 2021b;Arcadio et al, 2021c) and non-optimized plasmonic probes (Cenci et al, 2018b;Cennamo et al, 2020), ultimately enabling to modulate the sensor's response.…”

“…To date, in order to improve the optical response of the plasmonic sensors based on PMMA multimode slab waveguides, we have been exploiting the maximum potential of such a chip and have been taking full advantages 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), so to realize nanopatterns suitable for a nanoplasmonic sensor. In particular, we developed and tested nanoplasmonic sensors based on gold nanograting fabricated on the top of PMMA chips (Arcadio et al, 2021b;Arcadio et al, 2021c).…”

“…More specifically, to determine the role of the grating in the plasmonic phenomenon, periodic, and non-periodic configurations have been studied to show how an optimized sensor, in terms of bulk sensitivity, can be obtained exploiting a specific periodic nanopattern (Arcadio et al, 2021b). Additionally, the same PMMA nano-plasmonic sensor chips were monitored exploiting two different experimental configurations, both produced by our research group (Arcadio et al, 2021b;Arcadio et al, 2021c), where the PMMA substrate was considered as a transparent substrate in (Arcadio et al, 2021b), or a multimode waveguide in (Arcadio et al, 2021c), as in the present work. In the cases studied as a proof of concept, we functionalized the nano-grooved surface with a specific nanolayer of a MIP selective for bovine serum albumin (BSA) detection (Arcadio et al, 2021b;Arcadio et al, 2021c).…”

“…Additionally, the same PMMA nano-plasmonic sensor chips were monitored exploiting two different experimental configurations, both produced by our research group (Arcadio et al, 2021b;Arcadio et al, 2021c), where the PMMA substrate was considered as a transparent substrate in (Arcadio et al, 2021b), or a multimode waveguide in (Arcadio et al, 2021c), as in the present work. In the cases studied as a proof of concept, we functionalized the nano-grooved surface with a specific nanolayer of a MIP selective for bovine serum albumin (BSA) detection (Arcadio et al, 2021b;Arcadio et al, 2021c).…”