Facile synthesis of metal-phenolic-coated gold nanocuboids for surface-enhanced Raman scattering

Abstract

Metal-phenolic networks (MPNs) have been exploited to be a versatile coating film to fabricate core-shell structure due to their general adherent properties. Herein, gold nanocuboid (GNCB) wrapped by MPNs (GNCB at MPNs) are prepared by a facile encapsulation method for surface-enhanced Raman scattering (SERS) analysis. The MPN coating not only reshapes the electric field distribution around the nanostructures but also allows the substrate to adsorb more analytes, both of which contribute to the superior SERS activity of GNCB at MPNs. The SERS signals induced by plasmonic nanostructures increase four- to sixfold after MPN coating, reaching a maximum Raman enhancement factor calculated to be 9.47 × 1 0 8 . Moreover, the core-shell SERS substrate also demonstrates improved biocompatibility (∼fivefold increase) that facilitates the reliable SERS analysis of cancer cells and further diverse biomedical applications.

Fast Synthesis of Au Nanoparticles on Metal–Phenolic Network for Sweat SERS Analysis

“…After Au NPs generation, a strong LSPR peak at 540 nm emerges ( Figure 1 D), and the synthetic efficiency of Au-MPN is ideal ( Figure S1 ). The Raman spectra of MPN and Au-MPN ( Figure 1 E) show the characteristic Raman bands at 1350 and 1480 cm −1 , ascribing to the skeletal vibrations of the benzene ring [ 20 ]. In addition, the chemical composition of Au-MPN shows the common features of its precursors, as confirmed by the FT-IR spectra ( Figure 1 F), such as 1645 cm −1 (C=O stretching), 1440 cm −1 (C–O stretching), 1282 cm −1 (C–N stretching), 1192 cm −1 (O–H bending), and 1060 cm −1 (C–OH stretching) [ 26 , 38 , 39 ].…”

“…The performance of photoelectric sensors largely depends on the properties of materials. Metal–phenolic network (MPN), an outstanding organic-inorganic hybrid material firstly reported by Caruso’s group [ 15 ], has been widely used as a versatile coating material for multiple applications [ 16 , 17 , 18 , 19 , 20 ]. Different from other supramolecular structures, the construction cost of MPN is low, and its synthesis is extremely simple that can be assembled on a large scale within 20 s [ 21 ].…”

Tunable Nanomaterials of Intracellular Crystallization for In Situ Biolabeling and Biomedical Imaging

“…SERS has been widely used in biomedicine because of the acquisition of molecular fingerprint information. − The enhancement of Raman spectrum is generally through electromagnetic enhancement (EM) and chemical enhancement (CM) to achieve single molecule detection. − Most of the applications in biomedical analysis and imaging are realized by electromagnetic enhancement because of the low content of biomolecules. − Electromagnetic coupling occurs between noble metal nanoparticles, and surface plasmon resonance occurs locally. , Biosynthesis is the synthesis of noble metal nanoparticles in cells, bacteria and plants. This hint can be used for biomedical analysis and mapping of corresponding molecules.…”