Sericin-Based Bio-Inspired Nano-Engineering of Heterometallic AgAu Nanocubes for Attomolar Mefenamic Acid Sensing in the Mobile Phone-Based Surface Plasmon-Coupled Interface

Abstract

Engineering photo-plasmonic platforms with heterometallic nanohybrids are of paramount significance for realizing augmented sensitivity in fluorescence-based analytical detection. Although myriad nanomaterials with versatile functionalities have been explored in this regard in the surface plasmon-coupled emission (SPCE) interface, light harvesting using nano-antennas synthesized via sustainable bio-inspired routes still remains a high priority in current research. Our study provides a rational design for in situ fabrication of nanoparticles of silver, gold, and their plasmonic hybrids using biocompatible, non-hazardous sericin protein (obtained Bombyx mori) as the reducing and capping agent. The one-pot, user-eco-friendly technology demonstrated here utilizes UV irradiation to promote the photo-induced electron transfer mechanism, thereby yielding nanomaterials of tunable optoelectronic functionalities. The resulting homometallic and heterometallic nanohybrids with robust localized surface plasmon resonances (LSPR) showed strong light-confining attributes when interfaced with the propagating surface plasmon polaritons (SPPs) of the SPCE platform, thereby yielding tunable, highly directional, polarized, and amplified fluorescence emission. The experimentally obtained emission profiles displayed an excellent correlation with the theoretically obtained dispersion diagrams validating the spectro-plasmonic results. The abundant hotspots from AgAu nanocubes presented in excess of 1300-fold dequenched fluorescence enhancement and were utilized for cost-effective and real-time mobile phone-based sensing of biologically relevant mefenamic acid at an attomolar limit of detection. We believe that this superior biosensing performance accomplished using the frugal bioinspired nano-engineering at hybrid interfaces would open new doors for developing nanofabrication protocols with the quintessential awareness of the principles of green nanotechnology, consequently eliminating hazardous chemicals and solvents in the development of point-of-care diagnostic tools.

Nd2O3-Ag Nanostructures for Plasmonic Biosensing, Antimicrobial, and Anticancer Applications

“…Engineering low-loss nanophotonics platforms for enhanced optical performance has been achieved with HRI dielectric metasurfaces. − Functional HRI dielectric Nd 2 O 3 Huygens’ sources have been explored in photonic metasurfaces in our earlier works in different nanointerfaces. ,, The SPCE platform has been utilized to comprehend unique light-matter interactions at nanointerfaces demonstrating different physicochemical processes, biosensing, and insightful photonic-coupling applications. − Molecular emitters in the vicinity of nanomaterials and thin nanofilms exhibit intriguing phenomena. − The spacer nanomaterials such as 0D-nanodiamonds, graphene oxide (GO), 1D-carbon nanotubes (CNT), fullerenes (C60, C70), and AgCDs on the SPCE substrate have contributed in the augmentation of fluorescence emission enhancements and to the broad field of plasmonics on the basis of their unique material-chemistry characteristics. , Therefore, we studied the effect of NdAg FP in the spacer interface, and the results are presented in Figure i–k. Apart from the magnetic response from NdAg FP, the multiple hotspots generated between (i) NdAg-NdAg, (ii) NdAg-Ag thin film, (iii) AgNP-AgNP on adjacently located NdAg, (iv) NdAg-AgNPs, and (v) AgNP-AgNP of an individual NdAg hybrid presenting void plasmons, , delocalized Bragg, and localized Mie plasmons , have assisted in the realization of >400-fold fluorescence emission enhancements.…”

Photonic Crystal Enhanced Fluorescence: A Review on Design Strategies and Applications

“…The first two objectives have been explored in the past decade and concomitantly different processes, biosensing frameworks, and applications have been realized with the SPCE platform [ 66 , 199 , 200 , 201 , 202 , 203 , 204 , 205 ]. In spite of the wide-ranging applications rendered by the SPCE technology, the far-reaching capability of the platform has been hindered on account of the inevitable Ohmic losses intrinsically sustained by the SPCE platform [ 206 , 207 ]. In this regard, in an attempt to accomplish the third objective, Bhaskar et al developed a robust, lossless, and practical biosensing platform using a 1DPC with the potential to entirely replace the metallic thin films used in the SPCE platform.…”

Metal–Dielectric Interfacial Engineering with Mesoporous Nano-Carbon Florets for 1000-Fold Fluorescence Enhancements: Smartphone-Enabled Visual Detection of Perindopril Erbumine at a Single-molecular Level

“…The large sensitivity demonstrated along with the emission in the visible region provides a direct and rapid detection tool for integrating with mobile phone-based platforms. We execute this in line with our earlier works 16,19,21,51,82 using costeffective smartphone-based detectors, thereby replacing the complex, bulky, and expensive readout systems that are conventionally adopted. Accordingly, the images of the SPCE were captured using a smartphone and processed using the Color Grab app.…”