Quantitative surface‐enhanced resonance Raman scattering analysis of methylene blue using silver colloid

Abstract

Quantitative analysis of methylene blue (MB) has been performed with Surface Enhanced Raman Scattering, SERS, using citrate reduced silver colloid activated with NaCl. In this study, the combination of SERS occurring at the proximity of the plasmon surface and of resonance Raman with excitation wavelength matched to the maximum absorbance of the molecule being analyzed, was successfully applied to maximize the Raman scattering intensity. The surface‐enhanced resonance Raman scattering (SERRS) spectra of aqueous solutions of the dye at various concentrations were collected in right‐angle scattering geometry configuration which results favorable when nanocolloidal dispersions are used. The MB concentration was correlated with the intensity of the peak centered at 1,625 cm−1 in the SERRS spectrum and this correlation resulted in an extremely sensitive quantitative investigation of the MB with limit of detection in pM level. Among others, this method can be easily applied for the examination of both the selectivity of waste water purification membranes for relevant small molecular weight contaminants or/and the solar photocatalytic effectiveness of such membranes for the degradation of pertinent pollutants by their quantitative assessment in the permeate at very low concentration range.

Femtosecond Laser Fabricated Ag@Au and Cu@Au Alloy Nanoparticles for Surface Enhanced Raman Spectroscopy Based Trace Explosives Detection

“…Figure 6C shows the SERS spectra of MB (5 nM) with observed modes at 449, 776, 947, 1,175, 1,396, and 1,621 cm −1 are in good agreement with the earlier works [43]. The major MB peaks were located at 449, 1,621 cm −1 were assigned to skeletal deformation of C-N-C, Ring stretching of C-C, respectively [44] and the other peaks and their assignments were reported in earlier literature [13,45]. A strong peak at 520 cm −1 observed is from the silicon substrate with NPs (a break in spectra shown in Figure 6C) and also a broad flat edged peak between 900 and 1,000 cm −1 corresponds to the 2nd order Si Raman band.…”

Surface‐enhanced Raman scattering studies of gold‐coated ripple‐like nanostructures on iron substrate achieved by femtosecond laser irradiation in water

“…The high‐intensity Raman modes observed at 446 and 1620 cm −1 can be ascribed to the skeletal deformation of C‐N‐C and C‐C ring stretching. The lower intensity modes noticed at 499, 769, and 1,393 cm −1 are assigned to the C‐N‐C skeletal deformation, C‐H in‐plane bending, and C‐N symmetric stretching, which are in accordance with the earlier published results . Figure b presents the recorded SERS spectra of MB (5nM) from the FeDNS1, FeDNS2, and FeDNS3 substrates, and the noticed spectral modes are slightly shifted, which can possibly be due to the orientation of probe molecule on the NSs.…”

Impact of the anodization time on the photocatalytic activity of TiO2 nanotubes

“…The spectra of the electrolyte and Ti plate were considered as well, to cancel out their corresponding bands that are still visible in the solution spectra. The characteristic assignments for MB were within the range of 1800–250 cm −1 and have the following interpretation: C–N–C skeletal deformation (448 and 501 cm −1 ), C–S–C skeletal deformation (596 cm −1 ) in-plane bending mode C–H (770, 951 and 1154 cm −1 ), in-plane ring-deformation mode C–H (1302 cm −1 ), asymmetrical stretching C–C (1502 cm −1 ), and two prominent peaks for C–N symmetrical stretching (1394 cm −1 ) and C–C ring stretching (1623 cm −1 ) [91–92]. The vibrational bands observed in the recorded spectra agree with those values reported in the literature.…”