One-Step Preparation Method of Flexible Metafilms on the Water–Oil Interface: Self-Assembly Surface Plasmon Structures for Surface-Enhanced Raman Scattering Detection

Abstract

The present study demonstrated a one-step method for the first time to fabricate self-assembled gold nanoparticle (AuNP) metafilms at the water− toluene interface by adding polystyrene−polyisoprene−polystyrene as the support layer. The thiolated polyethylene glycol and ethanol were used to tune the surface charge density on the AuNPs, constructing a balanced situation at the water− toluene interface. The flexible (AuNP) metafilm can be easily obtained after evaporation of the toluene phase and further used as a surface-enhanced Raman scattering (SERS) substrate for trace thiram detection. The SERS sensitivity was tested using standard Raman probes such as crystal violet and malachite green, both with the detect concentration reaching 1 × 10 −11 M. Moreover, the excellent reproducibility and elastic properties make the metafilm promising in practical detection. Hence, the trace thiram detection on an orange pericarp was inspected with the detection limit of 0.5 ppm (1 × 10 −6 M) as well as a favorable linearity relation with a correlation coefficient of 0.979, exactly matching the realistic application requirements.

Retracted Article: Synergistic action of star-shaped Au/Ag nanoparticles decorated on AgFeO2 for ultrasensitive SERS detection of a chemical warfare agent on real samples

“…PE detection by SERS has significant impacts in various fields, such as analytical chemistry, life science, food safety, biomedical sensing and treatment. 11–13 Recently, a great deal of research has been devoted to develop solid SERS substrates, especially to detect analytes in the environment. To prepare solid substrates, simple and reliable methods such as drop-casting, immersion, aggregation, and self-assembly have been proposed.…”

Permeability of 3D Templates Plays a Considerable Role in Improving the Activity of 3D Composite Surface-Enhanced Raman Scattering Substrates

“…Traditional SERS substrates are usually prepared by depositing various nanocrystals on flat materials. Nevertheless, both the small adsorption area for probe molecules and lower light utilization limit the SERS performance of two-dimensional (2D) substrates. − To address this challenge, the design and establishment of three-dimensional (3D) SERS substrates with high density hot spots are an effective method. − The complex geometric structure of 3D SERS substrates could produce more hot spots in the same laser illumination region than 2D structures. Meanwhile, the larger specific surface area is not only conducive to the absorption of probe molecules on the metal nanoparticles but also improves the light utilization at the same region.…”

Contrastive Study of In Situ Sensing and Swabbing Detection Based on SERS-Active Gold Nanobush–PDMS Hybrid Film

“…18−20 Particularly, some novel strategies such as self-assembly and phase transfer have been proposed to combine these noble-metal nanostructures with poly(dimethylsiloxane) (PDMS) films, resulting in some flexible and transparent SERS substrates. 21,22 Nevertheless, there still exist some disadvantages such as long time, high cost, and low efficiency in the preparation. More poorly, the spherical NPs usually provide weak SERS effects, limiting their applications in the detection of trace analytes.…”