Large-Scale Fabrication of Nanostructure on Bio-Metallic Substrate for Surface Enhanced Raman and Fluorescence Scattering

Abstract

The integration of surface-enhanced Raman scattering (SERS) and surface-enhanced fluorescence (SEF) has attracted increasing interest and is highly probable to improve the sensitivity and reproducibility of spectroscopic investigations in biomedical fields. In this work, dual-mode SERS and SEF hierarchical structures have been developed on a single bio-metallic substrate. The hierarchical structure was composed of micro-grooves, nano-particles, and nano-ripples. The crystal violet was selected as reporter molecule and both the intensity of Raman and fluorescence signals were enhanced because of the dual-mode SERS−SEF phenomena with enhancement factors (EFs) of 7.85 × 105 and 14.32, respectively. The Raman and fluorescence signals also exhibited good uniformity with the relative standard deviation value of 2.46% and 5.15%, respectively. Moreover, the substrate exhibited high sensitivity with the limits of detection (LOD) as low as 1 × 10−11 mol/L using Raman spectroscopy and 1 × 10−10 mol/L by fluorescence spectroscopy. The combined effect of surface plasmon resonance and “hot spots” induced by the hierarchical laser induced periodical surface structures (LIPSS) was mainly contributed to the enhancement of Raman and fluorescence signal. We propose that the integration of SERS and SEF in a single bio-metallic substrate is promising to improve the sensitivity and reproducibility of detection in biomedical investigations.

Classification of Preeclamptic Placental Extracellular Vesicles Using Femtosecond Laser-fabricated Nanoplasmonic Sensors and Machine Learning

“…[44][45][46] These efforts have been directed solely towards LIPSS nanostructuring of base materials, such as silicon or glass, followed by the deposition of a SERS-active film of gold or silver. [47][48][49][50][51][52][53] Despite the potential benefits, fs-laser nanopatterning directly on SERS-active thin films…”

Attomolar Sensing Based on Liquid Interface-Assisted Surface-Enhanced Raman Scattering in Microfluidic Chip by Femtosecond Laser Processing

“…Specifically, besides the localized electric field, the SERS enhancement also depends on the analyte adsorption properties of the substrate and the SERS cross-section of the analyte molecule. To verify experimentally the SERS EF, the SERS analytical EF (AEF) was calculated using the expression AEF = ( I SERS / I OR )/( C SERS / C OR ), where I SERS and I OR correspond to the Raman intensities of R6G on the SERS substrate and on the glass, respectively, and C SERS and C OR denote the molar concentration of the R6G solution in the microfluidic SERS chip and on the glass, respectively. , The advantage of using the AEF to define the SERS enhancement is that the AEF should result in a reproducible value when all experimental procedures are clearly stated and controlled . Using the data of Figure a, the detection limit for the microfluidic SERS chips was 10 –9 M. The detection limit for the Raman measurement on glass was calculated to be 10 –2 M, as shown in Figure c (black line: ordinary).…”

An efficient dual functional Raman and Fluorescence detection platform achieved by controlling the electromagnetic enhanced field in three-dimensional Ag/ZnO composited arrays

“…S3a (ESI †), and the value of EF was estimated to be 8 Â 10 11 for our 20 min Ag/ZnO platform, which is higher than the previous report with an average EF of 10 7 -10 10 . 26,27 The detection limit of the R6G molecule was further evaluated with the optimized 20 min-Ag/ZnO NR samples and shown in Fig. S3b (ESI †).…”