Plasmonic Superstructure Arrays Fabricated by Laser Near-Field Reduction for Wide-Range SERS Analysis of Fluorescent Materials

Abstract

Surface-enhanced Raman scattering (SERS) enables trace-detection for biosensing and environmental monitoring. Optimized enhancement of SERS can be achieved when the energy of the localized surface plasmon resonance (LSPR) is close to the energy of the Raman excitation wavelength. The LSPR can be tuned using a plasmonic superstructure array with controlled periods. In this paper, we develop a new technique based on laser near-field reduction to fabricate a superstructure array, which provides distinct features in the formation of periodic structures with hollow nanoclusters and flexible control of the LSPR in fewer steps than current techniques. Fabrication involves irradiation of a continuous wave laser or femtosecond laser onto a monolayer of self-assembled silica microspheres to grow silver nanoparticles along the silica microsphere surfaces by laser near-field reduction. The LSPR of superstructure array can be flexibly tuned to match the Raman excitation wavelengths from the visible to the infrared regions using different diameters of silica microspheres. The unique nanostructure formed can contribute to an increase in the sensitivity of SERS sensing. The fabricated superstructure array thus offers superior characteristics for the quantitative analysis of fluorescent perfluorooctanoic acid with a wide detection range from 11 ppb to 400 ppm.

Ultraminiaturized Microfluidic Electrochemical Surface‐Enhanced Raman Scattering Chip for Analysis of Neurotransmitters Fabricated by Ship‐in‐a‐Bottle Integration

“…The silver nuclei induced LSPR to enhance the surface electric field and subsequently attracted the silver ions, leading to a continuous reduction process to form silver nanoparticles. [ 22 ] In addition, the synthesized silver nanoparticles were capped by citrate, indicating the presence of a strongly negatively charged surface (zeta‐potential: −39.66 mW). The negative charges were accumulated at the silver nanoparticle surface to facilitate the growth of silver nanoparticles.…”

Periodic Surface Structuring of Copper with Spherical and Cylindrical Lenses

“…Several applications of laser-structured surfaces have been already addressed in relation to their intriguing optical, wetting, mechanical, and biological-active properties [ 1 , 2 , 3 , 4 , 5 ]. However, they might express their potential in other fields like, for example, those pursuing the elaboration of nano-engineered plasmonic surfaces for SERS and metal-enhanced fluorescence [ 30 , 31 , 32 , 43 , 44 , 45 , 46 ].…”

Analysis of needs for enforcement of PFAS in articles and chemical products

“…Only few studies on the detection of PFAS using SERS have been reported today although there is an urgent need to develop rapid and ultrasensitive detection methods (M.B et al, 2023). In 2022, Bai et al created plasmonic superstructure arrays made of Ag nanoparticles and used them to detect PFOA during SERS analysis (Bai et al, 2022). To prevent luorescence and promote Raman signal detection, the authors incorporate crystal violet into PFOA.…”