Stationary, Continuous, and Sequential Surface‐Enhanced Raman Scattering Sensing Based on the Nanoscale and Microscale Polymer‐Metal Composite Sensor Particles through Microfluidics: A Review

Abstract

Surface‐enhanced Raman scattering (SERS) is a label‐free and accurate analytical technique for the detection of a broad range of various analytes such as, biomolecules, pesticides, petrochemicals, as well as, cellular and other biological systems. A key component for the SERS analysis is the substrate which is required to be equipped with plasmonic features of metal nanostructures that directly interact with light and targeted analytes. Either metal nanoparticles can be deposited on the solid support (glass or silicon) which is suitable for stationary SERS analysis or dispersed in the solution (freely moving nanoparticles). Besides these routinely utilizing SERS substrates, polymer–metal composite particles are promising for sustained SERS analysis where metal nanoparticles act as plasmon‐active (hence SERS‐active) components and polymer particles act as support to the metal nanoparticles. Composite sensor particles provide 3D interaction possibilities for analytes, suitable for stationary, continuous, and sequential analysis, and they are reusable/regenerated. Therefore, this review is focused on the experimental procedures for the development of multiscale, uniform, and reproducible composite sensor particles together with their application for SERS analysis. The microfluidic reaction technique is highly versatile in the production of uniform and size‐tunable composite particles, as well as, for conducting SERS analysis.

Recent Progress of Droplet Microfluidic Emulsification Based Synthesis of Functional Microparticles

“…Metal Microparticles: Due to the size and shape dependent properties, [112] metal microparticles play an extremely important role in metallic materials. As a result of a high ratio of surface area to volume, metal particles, especially in nanoscale, can be se-lected as effective catalysts for certain reactions.…”

MoS2 Nanoplatelets on Hybrid Core-Shell (HyCoS) AuPd NPs for Hybrid SERS Platform for Detection of R6G

“…The SERS has offered fascinating opportunities for a wide range of applications such as optoelectronics, photocatalysis, gas sensors, energy harvesting, etc. [ 4 , 5 , 6 ]. Regarding SERS enhancement mechanisms, the electromagnetic mechanism (EM) has been widely adapted as a dominant mechanism for various configurations of metallic micro- and nano-structures [ 5 , 6 , 7 , 8 ].…”

“…[ 4 , 5 , 6 ]. Regarding SERS enhancement mechanisms, the electromagnetic mechanism (EM) has been widely adapted as a dominant mechanism for various configurations of metallic micro- and nano-structures [ 5 , 6 , 7 , 8 ]. The EM is induced by the photon-driven excitation of localized surface plasmon resonance (LSPR), enabling giant enhancement of local e-fields that are significantly stronger than the incident photon [ 9 , 10 , 11 , 12 ].…”

The volatile release evaluation of nicotine from snus products under different storage conditions based on surface-enhanced Raman spectroscopy technology

“…Here, it is worth mentioning that the development and application of SERS technology depend on the design of the substrates as well as the construction of the corresponding module. [17][18][19][20][21][22] For many more substrates, especially practical SERS substrates, their current development needs to consider the characteristics of high reliability, fast operation, easy maintenance and portability. [23][24][25] Researchers found that binary nano-or micro-particles composed of a superparamagnetic core and Au or Ag nanoshell, such as Fe 3 O 4 microparticles coated with Au nanorods (Fe 3 O 4 @-AuNRs), 26 Fe 3 O 4 coated with Au nanoparticles (Fe 3 O 4 @-AuNPs), 27 etc., have a lot of advantages.…”