Mesoporous silica coated core-shell nanoparticles substrate for size-selective SERS detection of chloramphenicol

• Published in: Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy Vol. 284; p. 121817
• Main Authors: Jayan, Heera, Sun, Da-Wen, Pu, Hongbin, Wei, Qingyi
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 05.01.2023
• Subjects: Au@Ag@mSiO2NP substrate; Chloramphenicol; Mesoporous structure; SERS; Chloramphenicol; Mesoporous structure; SERS; Au@Ag@mSiO2NP substrate
• ISSN: 1386-1425
• DOI: 10.1016/j.saa.2022.121817

[Display omitted] •Mesoporous silica coating was achieved on Au@Ag core–shell nanoparticles.•Au@Ag@mSiO2NP showed high enhancement ability for SERS detection.•Mesoporous silica coating provides selective screening based on molecular size.•Chloramphenicol was detected with a limit of detection of 6.68 × 10−8 M.•Au@Ag@mSiO2NP showed stability over long period of storage. With the growing popularity of the non-destructive technique, surface-enhanced Raman spectroscopy (SERS) demands a highly sensitive and reproducible plasmonic nanoparticles substrate. In this study, a novel bimetallic core–shell nanoparticles (Au@Ag@mSiO2NP) substrate consisting of a gold core, silver shell, and a mesoporous silica coating was synthesized. The mesoporous coating structure was created by employing template molecules such as surfactant and their subsequent removal allowing selective screening based on the size of analyte molecules. Results showed that the plasmonic substrate could selectively enhance small molecules by preventing large macromolecules to reach the exciting zone of the substrate core, achieving the detection of chloramphenicol in milk samples with a detection limit of 6.68 × 10−8 M. Moreover, the mesoporous coating provided additional stability to the Au@Ag nanoparticles, leading to the reusability of the substrate. Thus, this work offered a simple and smart Au@Ag@mSiO2NP substrate for effective SERS detection of analytes.