Multifunctional hybrid soret nanoarchitectures for mobile phone-based picomolar Cu2+ ion sensing and dye degradation applications

Cellphone-Aided Attomolar Zinc Ion Detection Using Silkworm Protein-Based Nanointerface Engineering in a Plasmon-Coupled Dequenched Emission Platform

“…After the polymer matrix (doped with appropriate dye or NPs) is spin-coated on the SPCE substrate (50 nm Ag thin film), the samples are allowed to dry under ambient conditions (in a clean room facility) for 3–4 min. Consequently, the polymer is completely dried before spin-coating the next layer in this multi-nanoarchitecture substrate engineering approach. ,,,− In light of these observations, although the subsequent polymer film coating is a simple physical adsorption, the initial layers are not washed (or disturbed) because of prior drying.…”

“…On account of the multifold hotspots (regions of high EM fields in nanogaps and nanocavities) generated, the fluorescence emission was not only dequenched but also amplified to >1300-fold, this has not been reported until date using the SPCE platform. Although different materials such as intermetallics (TiC, TiN, and TiCN), high-refractive-index dielectrics, ,, low-dimensional carbon substrates, and soret nanoassemblies have been explored in different nanointerfaces in the SPCE platform, the enhancements have remained moderate. In this context, the nanogaps represent the nanoscopic regions generated between the NPs or within an anisotropic NP.…”

Plasmon-Coupled Directional Emission from Soluplus-Mediated AgAu Nanoparticles for Attomolar Sensing Using a Smartphone

“…In our case, in RK optical configuration, the emission is expected at angles where minimum reflectivity is expected theoretically, in line with our earlier works. 7,19,35 In this context, we have carried out TFClac simulations to theoretically understand the expected angle of emission and to further correlate them with the experimental values. From Figure 2a,b, we note that a sharp dip in the reflectivity is observed for p-polarized or transverse magnetic component of light.…”

“…7−11 The near-field optical confinement provided by the plasmonic NPs generate regions of intense EM "hotspots", when coated on a metal thin film. 16,17 Although a variety of NPs including low-dimensional materials, 18 self-assembled soret colloids, 7 and intermetallics 19,20 have been studied for their photoplasmonic contribution to SPCE, physicochemical evaluation of gold (Au) NPs has been inadequate on account of inevitable quenching of fluorophores located in distances <5 nm. In comparison to other coinage NPs (Ag, Pt, Pd), AuNPs exhibit manifold functionalities due to high stability with precise geometries, extraordinary optoelectronic properties, superior biocompatibility, tunable biophysicochemical properties and ability for multifunctionalization with inorganic/ biological/organic ligands.…”

“…Recently, research efforts have been devoted to synergize PEF and SPCE into a single hybrid platform. − , Generally, the enhancement factor of SPCE substrate is 5–10-fold as compared to traditional luminescence. − , Lakowicz and co-workers have demonstrated the significance of silver (Ag) NPs spacer layer engineering on SPCE platform to further augment the enhancement to 60-fold . With this as a preliminary step for combining PEF and SPCE, diverse nanoarchitectures have been explored to further augment the SPCE enhancements. − The near-field optical confinement provided by the plasmonic NPs generate regions of intense EM “hotspots”, when coated on a metal thin film. , Although a variety of NPs including low-dimensional materials, self-assembled soret colloids, and intermetallics , have been studied for their photoplasmonic contribution to SPCE, physicochemical evaluation of gold (Au) NPs has been inadequate on account of inevitable quenching of fluorophores located in distances <5 nm. In comparison to other coinage NPs (Ag, Pt, Pd), AuNPs exhibit manifold functionalities due to high stability with precise geometries, extraordinary optoelectronic properties, superior biocompatibility, tunable biophysicochemical properties and ability for multifunctionalization with inorganic/biological/organic ligands .…”