Probing the enhancement mechanisms of SERS with p-aminothiophenol molecules adsorbed on self-assembled gold colloidal nanoparticles

SERS-based nanobiosensing for ultrasensitive detection of the p53 tumor suppressor

“…The vibrational bands found in the selected wave number region where the main spectral changes occur are listed in Table 1, together with the literature-based assignments. [45][46][47][48] We can note striking differences between the spectra of the 4-ATP linker before ( Figure 2A) and after ( Figure 2B) conjugation with the gold nanoparticles. Indeed, the formation of an S-Au covalent bond, indicative of conjugation of 4-ATP with gold nanoparticles, is evident from the disappearance of the band centered at 2550 cm −1 , inherent to the stretching vibration of S-H (see the insets of Figure 2A and B).…”

“…19,29,30 For 4-ATP molecules bound to gold nanoparticles, the enhancement of bands at about 1141 cm −1 and 1435 cm −1 seen in Figure 2B can be ascribed to the charge transfer mechanism, while the other bands reported in Table 1 for 4-ATP nanoparticles are thought to be selectively enhanced mainly via electromagnetic mechanisms. [45][46][47][48] From the signal to noise intensity ratio of the C-S stretching mode (around 1089 cm −1 and 1078 cm −1 for the solid 4-ATP and the 4-ATP nanoparticle system, respectively), enhancement due to a SERS effect of about seven orders of magnitude was estimated.…”

Multilayer Structures of Self‐Assembled Gold Nanoparticles as a Unique SERS and SEIRA Substrate

“…Nowadays, it is difficult to find a review paper on nanoscale optical properties that does not recommend SERS as the first example of applications. However, the astonishing research interest manifested today concerning how to control, manipulate, and amplify light on the nanometer length scale by using the properties of the collective electronic excitations in noble-metal films or nanoparticles has prompted the resurgence not only of SERS, [4,[11][12][13][14][15][16][17] but also of SEIRA techniques. [18][19][20][21][22] The enhancement of both Raman and IR signals is of particular interest because of the efficiency of these spectroscopic methods in elucidating molecular structures and obtaining complete information on the adsorption behavior and orientation of molecular species.…”

Applications of the Planar Fiber Optic Chip

“…Raman activity of p-ATP in the presence of gold SERS substrates has been well documented. (Baia et al, 2006;Guo et al, 2007;Wang et al, 2008) The analyte was deposited onto the FOC by submersion in an ethanol solution overnight. The FOC was washed and dried under a nitrogen flow before analysis of the thin-film.…”