A portable microcolumn based on silver nanoparticle functionalized glass fibers and its SERS application

Abstract

We presented a facile method for the preparation of a portable detection column integrated with silver nanoparticle (Ag NP) functionalized glass fibers for surface-enhanced Raman scattering (SERS). Ag NPs were immobilized onto the surface of fibers through a two-step self-assembly process, and the cycling of the assembly process was repeated to optimize the SERS activity. The optimized fibers coated with homogeneous and dense Ag NPs were combined with a glass column, displaying good reproducibility. This combination could construct more "hot spots" and the spatial intra-channel structure for high mass transfer, and provide more sufficient interactions between the probing laser and metallic nanoparticles. The capability of the prepared column to have high sensitivity to dyes was demonstrated by the measurements of rhodamine 6G, alizarin red and methyl orange, with low concentrations of 28 pM, 64 pM and 0.36 nM, respectively. The SERS-active column fabricated by a facile, low-cost and high-yield approach is expected to be an effective and practical means for on-site application when rapid separation and detection of analytes in the liquid sample is needed.

Ultrasensitive and in situ DNA detection in various pH environments based on a microfiber with a graphene oxide linking layer

“…Silica ber is a cost-effective, exible, and widely available material. 33,34 Taking advantage of the miniature size and mechanical exibility, the optical ber allows integration with current medical tools for sensing in inaccessible locations. And it could realize the measurement of biological molecules through ber surface functionalization.…”

Tailoring Size and Coverage Density of Silver Nanoparticles on Monodispersed Polymer Spheres as Highly Sensitive SERS Substrates

“…As shown in Figure 1f,t he CPS spheres are almostc ompletely degraded by 600 8Ca nd the residual in the CPS/Ag hybrid particles after pyrolysis can be deemed to be the content of Ag in the hybrid particles. The contentso fA gi nt he hybrid particles gradually rises from 16,19,30,39 to 44 wt %a si ncreasing the amount of AAf rom 0, 5, 10, 15, to 20 wt %, respectively,w hich indicates that more negatively charged ÀCOOH groups can capturem ore silver ions, which are then reduced to more AgNPs. These resultsd emonstrate that the presence of surface ÀCOOH groupsf acilitates the homogeneous attachment of Sn 2 + ions and Ag + ions onto the CPS spheress urfaces by electrostatic interaction, resulting into au niform coverage of Ag nucleia nd finally AgNPs upon redox reaction.…”

“…[3,4,12] Gu and co-workers prepared ap ortable detection columni ntegrated with AgNPsf unctionalized glass fibers for SERS through at wo-step self-assembly process. [19] Although the self-assembly method is effective fort he immobilization AgNPs ontov arious carriers,t he self-assembledn anostructures are weakly bondedo nt he templates and susceptible to the externale nvironment, such as pH andc hemical constituents of the analyte, resulting in poor versatility of the SERS substrate. Li et al prepared Ag nanoparticles coatedp oly(styrene-coacrylic acid) composite spheres by in situ chemical reduction using polyvinyl pyrrolidone (PVP) as reductants.…”

“…For instance, Guerrini's group reported several studies using AgNPs uniformly coated inorganic particles, including silica and polystyrene microbeads, as SERS substrates via the layer‐by‐layer (LBL) self‐assembly method to detect heavy metal inorganics and investigate the correlations between the size of metal NPs and SERS properties . Gu and co‐workers prepared a portable detection column integrated with AgNPs functionalized glass fibers for SERS through a two‐step self‐assembly process . Although the self‐assembly method is effective for the immobilization AgNPs onto various carriers, the self‐assembled nanostructures are weakly bonded on the templates and susceptible to the external environment, such as pH and chemical constituents of the analyte, resulting in poor versatility of the SERS substrate.…”

Dense AuNP/MoS2 hybrid fabrication on fiber membranes for molecule separation and SERS detection

“…24 Compared to monolithic substrates, the glass ber offers a large surface area for adsorption due to its 3D structure and immobilizes SERS-active nanoparticles onto the interior surface of the capillary to avoid oating of the nanoparticle aggregates on the surface; this can highly improve reproducibility, enhance Raman signals of molecules, and extend its application. 25,26 In addition, GF membranes composed of intricate bers allow paper chromatographic separation under the action of capillary effect, which are feasible for the separation and preconcentration of analytes from a complex substrate. Paper, as a substrate, has been used for the separation and detection of complex samples.…”