Attenuated Total Reflection Surface-Enhanced Infrared Absorption (ATR SEIRA) Spectroscopy for the Analysis of Fatty Acids on Silver Nanoparticles

Abstract

The application of attenuated total reflection surface-enhanced infrared absorption spectroscopy (ATR SEIRA) to the analysis of fatty acids on silver nanoparticles was investigated. Attenuated total reflection measurements using four types of internal reflection elements (IREs)-zinc selenide, diamond, silicon, and germanium-were performed for silver nanoparticles modified with fatty acids, and germanium IRE was shown to be suitable for the analysis of silver nanoparticles, even when the sample had a high refractive index. Fatty acids coating the silver nanoparticles could be directly identified by SEIRA enhancement, because both symmetric carboxylate stretching vibration and methylene wagging vibration were strongly detected. Furthermore, the peak positions for methylene wagging vibration differed depending on the carbon number of the fatty acid, so that information from the ATR SEIRA spectra makes it possible to identify substances coating silver nanoparticles. Therefore, ATR SEIRA would appear to have significant potential as a technique for the identification of substances coated on metal nanoparticle surfaces.

Recent Advances in Silver Nanostructured Substrates for Plasmonic Sensors

“…The application of this sensor for shale gas measurement was reported, which is very useful for exploring natural resources. Similarly, an ATR SEIRA analysis of fatty acids was also successfully performed on silver nanoparticles [ 202 ]. Apart from this, many recent review articles have covered the field of biosensors using SEIRA [ 203 , 204 ].…”

Adaptive gold/vanadium dioxide periodic arrays for infrared optical modulation

“…Many applications have emerged from the field enhancement of the LSPR of specific optoelectronic devices, applications ranging from energy harvesting to ultra-sensitive physical, chemical, and biological sensors [5][6][7]. For all of these applications, developing adapted systems with a tunable LSPR position is a challenge of paramount importance [8][9][10][11][12][13][14][15][16]. Significant steps have been made, predominantly in the visible part of the electromagnetic spectrum through the geometrical manipulation of rounded noble metallic nanoparticles of Au and Ag elements associated to different surrounding environments [17][18][19][20][21][22][23][24][25][26][27].…”