Surface-enhanced Raman Scattering and Localized Surface Plasmon Resonance Detection of Aldehydes Using 4-ATP Functionalized Ag Nanorods

Abstract

Formaldehyde, acetaldehyde, and benzaldehyde are well-known carcinogens affecting human health adversely. Thus, there is a need for efficient detection of these aldehydes. This work uses 4-aminothiophenol (4-ATP) functionalized silver nanorods (Ag NRs) to detect these three aldehydes. The detection mode includes localized surface plasmon resonance (LSPR) and surface-enhanced Raman scattering (SERS). The LSPR band of 4-ATP functionalized Ag NRs shows a linear decrease in absorbance with the increase in formaldehyde and acetaldehyde concentrations. A sensitivity of 0.96 and 0.79 ΔA/mM for formaldehyde and acetaldehyde were obtained. In the case of benzaldehyde, a nearly exponential decrease in absorbance with the increase in concentrations was observed. Above 98.4 μM concentration, the absorbance diminishes completely. The LoD for formaldehyde and acetaldehyde detection using LSPR is 33.8 and 24.6 μM, respectively. The SERS studies reveal that the 4-ATP binds to Ag NRs through both –SH and –NH2 groups and facilitates the inter-particle charge transfer process. The appearance of b2 modes of vibration for 4-ATP evidences this charge transfer process. In the presence of aldehydes, the change in the band shape, relative intensities, and band position were observed primarily in b2 modes of vibration, evidencing the modulation in the charge transfer process. These remarkable changes were seen in μM concentration of aldehydes. Therefore, detection of these aldehydes with 4-ATP functionalized Ag NRs using SERS is possible in concentrations as low as ~ 1 μM.

Visible-Range Multiple-Channel Metal-Shell Rod-Shaped Narrowband Plasmonic Metamaterial Absorber for Refractive Index and Temperature Sensing

“…A microwave frequency band of a PMA was first proposed by Landy et al in 2008 [ 19 ]. The absorption enhancement of an incident EM wave in a PMA is attributed to different patterns of mode resonances, e.g., LSPR, surface lattice resonance (SLR) [ 20 , 21 , 22 ], surface plasmon polariton resonance (SPPR) [ 23 , 24 , 25 ], gap plasmon resonance (GPR), and cavity plasmon resonance (CPR) [ 26 , 27 , 28 ]. After then, a variety of works were proposed to concern the absorptance response of a PMA working at the frequency range from a microwave [ 29 ] through terahertz (THz) [ 30 ], infrared [ 31 , 32 ], and into the visible region [ 33 , 34 , 35 ].…”

“…It contains many exotic EM properties, which have many potential applications in nanophotonics. To improve sensor performance, many structures have been designed on metallic SPP-based subwavelength systems, including grooves [ 43 , 44 ], nanohole arrays [ 45 ], nanorods [ 46 , 47 ], nanorings [ 29 , 48 ], nanodisks [ 21 , 30 ], and so on. Callewaert et al designed a PMA structure based on a dielectric nanoring array on the Ag layer with absorption intensities as large as 95% [ 34 ].…”

Highly Stable 11-MUA Capped Gold Nanobipyramid for Refractive Index Sensing

“…In the recent past, we have worked on the synthesis and evaluation of refractive index (RI) sensitivity of silver [19][20][21][22] and gold nanostructures [23]. In J of Biomedical Photonics & Eng 9(1) 2023 24 Mar 2023 © J-BPE 010308-2 continuation, here we report the synthesis and RI sensitivity of Au nanobipyramids.…”