Surface-enhanced Raman scattering (SERS) spectroscopy is one of the most powerful analytical techniques in which significant field enhancement can be realized upon adsorption of molecules (analytes) on the surface of metal nanostructure that allow detection (sensing) of analytes at a very lower concentration. A key element for the better outcome through this method is the SERS substrate that needs to be equipped with plenty of hotspots as well as metallic rich and relatively roughened surface. Despite a large number of SERS substrates are routinely utilizing, there is still room and hence search is continuing for the dynamic substrates that reveal the extraordinary signal outcome. Polymers can provide the platform to meet such requirements by systematically depositing metal nanostructures at the surface. Polymer supported sensor particles (as substrate) are versatile due to the fascinating characteristics of the polymers such as swellability, porosity, transparency, metal loading ability, and high surface area. Microfluidics is a promising technique for the fabrication of polymer-supported sensor particles of nanoscale and microscale with uniformity. For nanoscale sensor particles, the metal nanoparticles can be incorporated and anchored at the surface of polymer nanoparticles electrostatically, and a ligand-free metal layer can be deposited by a metal-catalyzed metal enforcement process. Here, the development of the polymer-metal composite particles at nanometer and micrometer length scales, and their applications as sensor particles for SERS sensing are presented. Microfluidic techniques were utilized for the generation of uniform sensor particles with the precise distribution of metal nanoparticles in the interior and at the surface. Furthermore, metal-catalyzed metal enforcement approaches initiated for achieving a ligand-free metal surface for direct analyte interactions, and experimental demonstration of sequential SERS analysis of multiple analytes through microfluidics has been established.

Multiscale metal-polymer composite sensor particles for surface-enhanced Raman scattering (SERS) sensing through microfluidics

ACS Fall 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.