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Updated: May 29, 2026

Observation and Analysis of Blinking Surface-enhanced Raman Scattering
Published on: January 11, 2018
Fluorescence and Raman study of pH effect on the adsorption orientations of methyl red on silver colloids
Szetsen Lee1, Jian-How Wong, Shiao-Jun Liu
1Department of Chemistry, Center for Nano-technology, and Research Center for Analysis and Identification, Chung Yuan Christian University, Jhongli, Taoyuan, 32023, Taiwan. slee@cycu.edu.tw
Abstract:
We report the fluorescence and surface-enhanced Raman scattering (SERS) analysis of methyl red (MR) isomers (o-MR, m-MR, p-MR) on silver (Ag) colloids at different pH conditions. The changes in simultaneous fluorescence quenching around 400 nm accompanied by enhancement around 540 nm with pH are closely related to energy transfer efficiency and the interaction between the carboxylic group and the Ag surface. The change of SERS signals with pH values can be ascribed to different adsorption orientations of MR on the Ag surface, from near flat (o-MR) to near perpendicular (p-MR).
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