In situ detection of fluid media based on a three-dimensional dendritic silver surface-enhanced Raman scattering substrate

Abstract

In this paper, a highly active surface enhanced Raman scattering (SERS) substrate based on a three-dimensional (3D) dendritic silver nanostructure was constructed in a microfluidic channel by a one-step electrodisplacement reaction for in situ detection of fluid media. The finite difference time domain (FDTD) method was used to simulate the mechanism of multiple surface plasmon resonance of dendritic silver structures. The results showed that the existence of secondary branches in silver dendrites could produce stronger local electric field, which verified the effectiveness of the SERS substrate. In addition, the in situ analysis performance of the microfluid-SERS detection system was investigated in different concentrations of rhodamine 6G (R6G), with a detection limit up to 10⁻¹⁰ mol L⁻¹. The successful practice of this method opened a new way for the fabrication of high-performance microfluidic-SERS integrated sensor systems, and is expected to become a powerful analytical tool in the field of ultra-sensitive and rapid in situ analysis.