Silver Nanoparticle-Decorated Chitosan Aerogels as Three-Dimensional Porous Surface-Enhanced Raman Scattering Substrates for Ultrasensitive Detection

Abstract

Surface-enhanced Raman scattering (SERS) has attracted widespread attention because of its high sensitivity and label-free detection capabilities. Here, chitosan aerogels decorated with Ag nanoparticles (CAA) are used as a three-dimensional (3D) SERS substrate to achieve ultrasensitive detection. The CAA produces a high specific surface area and high porosity, which generates numerous hot spots and adsorption sites for SERS. With crystal violet as a probe molecule, a SERS enhancement factor of 1.4 × 109 was realized, with a detection limit of 10–13 M. Furthermore, quantitative detection in the 10–5–10–10 M range and good reproducibility were achieved. This work proposes a cost-effective aerogel-based SERS substrate with high sensitivity and reproducibility.

Antibacterial nanocomposite of chitosan/silver nanocrystals/graphene oxide (ChAgG) development for its potential use in bioactive wound dressings

“…On the other hand, to identify the characteristic bands of chitosan and silver nanocrystals, these are indicated based on what is cited in the literature, which indicates that chitosan can be found at 2885 cm −1 and 1654 cm −1 43 , mainly the amine group of chitosan at 1593 cm −1 44 . While AgNCs are concerned, as previously reported, where these nanostructures have decorated chitosan in aerogel, they showed an important interaction in the range of 1000–1800 cm −1 45 , precisely where the ChAgG spectrum widens enormously, overlapping between them, the signals are interacting, corresponding to the D and G bands of graphene, chitosan and silver nanocrystals. This broadening has also been documented when silver nanocrystals interact with graphene bilayers 46 .…”

Effective adsorption of heavy metal ions in water by sulfhydryl modified nano titanium dioxide

“…(Cardinal et al, 2017;Grasseschi and Toma, 2017;Sun et al, 2019;Sahin et al, 2022). In our experiment, silver nanowires supported by cellulose film were used as the reinforcement substrate, (Koh et al, 2021;Feng et al, 2022) so as to improve the accurate characterization of related groups of nano TiO 2 -SH hybrid materials and accurate detection of the heavy metal adsorption process of materials in Raman test (Figure 3A). In the Raman test results, the characteristic peaks at 142 cm −1 , 395 cm −1 , 513 cm −1 and 637 cm −1 were corresponding to nano TiO 2 , which proved that nano TiO 2 was successfully synthesized (Supplementary Figure S5).…”

Ag Aerogel-Supported Single-Atom Hg Nanozyme Enables Efficient SERS Monitoring of Enhanced Oxidase-Like Catalysis

“…Over the past few years, aerogels with macroscopic dimensions have been demonstrated as promising supports to enhance single-atom metal loading. , A three-dimensional (3D) porous network architecture and abundant interaction sites of the aerogels promote the number of active centers through the loading of SACs, which can effectively inhibit the aggregation of active sites and activity weakening. Because of their excellent characteristics, aerogels are also broadly used in many fields, such as the electrochemistry process, oil–water separation, and surface-enhanced Raman spectroscopy (SERS). − For SERS application, the porous structure of the aerogel is beneficial to achieving rich “hot spots”, which endows it with a high sensitivity to detect liquid and gas analytes. − …”