SERS Research Applied to Polymer Based Nanocomposites

Abstract

Polymer based nanocomposites containing metal nanoparticles (e.g. Au, Ag) have gained increased attention as a new class of SERS (Surface Enhanced Raman Scattering) substrates for analytical platforms. On the other hand, the application of SERS using such platforms can also provide new insights on the properties of composite materials. In this chapter, we review recent research on the development of SERS substrates based on polymer nanocomposites and their applications in different fields. The fundamentals of SERS are briefly approached and subsequently there is a reference to the strategies of preparation of polymer based nanocomposites. Here the main focus is on SERS studies that have used a diversity of polymer based nanocomposites, highlighting certain properties of the materials that are relevant for the envisaged functionalities. A final section is devoted to the joint use of Raman imaging and SERS in nanocomposites development, a topic that presents a great potential still to be explored as shown by the recent research in this field.

Dendrimer‐Based Gold Nanostructures for SERS Detection of Pesticides in Water

“…Several differences are noticeable by comparing the conventional Raman spectrum of thiram with the corresponding SERS spectrum. These differences arise mostly because in the SERS spectrum the spectroscopic fingerprints result from thiram adsorbed on the Au surfaces . The most pronounced difference is the absence of certain vibrational bands (e.g.…”

“…These differences arise mostly because in the SERS spectrum the spectroscopic fingerprints result from thiram adsorbed on the Au surfa- ces. [45][46][47][48][49] The most pronounced difference is the absence of certain vibrational bands (e.g. 389, 845 and 1035 cm -1 ) along with the enhancement of the Raman band at 1376 cm -1 .…”

“…389, 845 and 1035 cm -1 ) along with the enhancement of the Raman band at 1376 cm -1 . Previous reports have suggested that the enhancement of the band at 1376 cm -1 is due to the proximity of the methyl CH 3 and CN groups (Table 1) to the surface of metal nanoparticles [45][46][47][48][49] Note that a detection limit of 10 nM in thiram was achieved by considering this Raman feature as a diagnosis band (1376 cm -1 ). Although for this analyte concentration the band has low intensity, it was assessed as distinct from the background noise.…”

“…For example, the dendritic structure of the polymer, which mimics natural structures such as tree roots, can be regarded as a means for the selective entrapment of chemical species to be detected at the surface of the metallic nanoparticles. This synergistic behavior, together with the well‐known colloidal stability of these systems in aqueous solutions, can be exploited in surface techniques such as the SERS analysis of trace levels of water contaminants , , . However, the research reported on the use of colloidal dendrimer based plasmonic nanostructures for SERS analysis is relatively scarce .…”

“…This synergistic behavior, together with the well-known colloidal stability of these systems in aqueous solutions, can be exploited in surface techniques such as the SERS analysis of trace levels of water contaminants. [20,21,[40][41][42][43][44][45][46][47] However, the research reported on the use of colloidal dendrimer based plasmonic nanostructures for SERS analysis is relatively scarce. [19][20][21]48] To the best of our knowledge, none of these systems have been developed for the trace analysis of molecular pesticides as water contaminants.…”