A highly reproducible and sensitive fiber SERS probe fabricated by direct synthesis of closely packed AgNPs on the silanized fiber taper

A surface-enhanced Raman scattering (SERS) tapered fiber probe has been developed by using a chemically-etched tapered fiber tip and silanization of the surface of the fiber taper, followed by the hydrothermal growth of silver nanoparticles (AgNPs) on the silanized fiber taper. 4-Aminothiophenol (4-ATP) was selected as the target analyte to study the SERS responses of the prepared fiber SERS probe in an optrode remote detection mode. The experimental results show that the prepared fiber probe exhibited the ability to detect the 4-ATP molecule at a concentration as low as 10-9 M and good reproducibility with the relative standard deviation (RSD) values being less than 9.1% for the strongest Raman peak. This work gives a novel and reliable way to realize a fiber SERS probe with high sensitivity, long-term stability, good reproducibility, and superior recyclability, exhibiting potential in SERS-based in situ detection application.