Single-Step Fabrication of High-Throughput Surface-Enhanced Raman Scattering Substrates

Abstract

The combination of surface-enhanced Raman scattering (SERS) with high-throughput screening (HTS) has significant importance for highly sensitive and massive workload assays. Although fabrication of HTS-SERS substrates can be achieved by several methods, the high cost as well as large-equipment dependence limit their applications. Here, we report a simple method to fabricate HTS-SERS substrates within one-step process. The HTS-SERS substrate is fabricated by simply UV-irradiating a fluoroalkylsilane (FAS)-modified liquid-repellent TiO surface in AgNO solution through a photomask. Owing to the photocatalytic nature of TiO, the UV irradiation simultaneously triggers the degradation of the attached FAS and the generation of liquid-adhesive Ag nanoparticles (NPs) on exposed area. A HTS-SERS substrate could be directly obtained after UV irradiation. The deposited Ag NPs evidently enhance Raman signals, and the significant difference between the wettability of exposed area and masked area enables fast formation of high-throughput liquid droplet arrays through a simple dragging solution process. The fabrication method is applicable to various substrate materials, to introduce additional functionalities. The photocatalytic activity of TiO also allows us to photobleach the residual analyte and Ag NPs after detection to recycle substrate. This single-step method is a highly promising candidate for the fabrication of HTS-SERS substrates.

UV‐Triggered Polydopamine Secondary Modification: Fast Deposition and Removal of Metal Nanoparticles

“…Interestingly, although the use of UV irradiation speeded up the reduction and Ag NP density significantly, the good uniformity and dispersity of Ag NPs were well maintained, as Figure S2 (Supporting Information) shows (the size and density of Ag NPs on these samples, as shown in Figure S3 (Supporting Information), demonstrate that both size and density of Ag NPs increased with UV irradiation time as well as UV light intensity). This observation/uniformity was different from conventional photoreduction methods based on a photocatalytic semiconductor, such as TiO 2 , which generates anisotropic MNPs with large size distribution and uncontrollable morphology under UV irradiation . The reason for this phenomenon is not clear yet, but we assume that PDA might act as a capping agent to stabilize and confine the deposited Ag NPs, in addition to reducing metal cations …”

Photo‐Adjustable TiO2‐Paper as a Smart Substrate for Paper‐Based Analytical Devices

“…The superior photocatalytic and photo‐degradation properties of TiO 2 provide a good countermeasure to such problems. [ 32 ] To demonstrate this, we used an organic dye “methylene blue” as the sample molecule to test photocatalytic degradation property of the TiO 2 ‐paper μPADs. The microfluidic patterns loaded with methylene blue was prepared by UV illumination on FDT‐TiO 2 ‐paper under a photomask.…”

pH-responsive SERS substrates based on AgNP-polyMETAC composites on patterned self-assembled monolayers

“…These investigations have been performed on microstructured substrates which allowed the fabrication of micropatterned brush systems. While the microstructure is in our studies beneficial because of a simplified and reliable characterization of the polymer brushes at defined sample areas, the introduction of the microstructured brush system is regarded moreover attractive for the development of highthroughput platforms for rapid, automated screening and analysis applications [34]. In this contribution, the introduction of the microstructured polymer brushed provides mainly a good possibility to easily compare the influence of different pH value conditions on the SERS enhancement, independent of in the brush morphology or the local filling factor of the Ag NPs.…”