A robust nanofilm co-assembled from poly(4-vinylpyridine) grafted carbon nanotube and gold nanoparticles at the water/oil interface as highly active SERS substrate for antibiotics detection

The preparation of robust and uniform surface-enhanced Raman scattering (SERS) substrate with high sensitivity and good reproducibility for practical applications remains a challenge. In this work, we develop a general strategy to fabricate robust nanofilms co-assembled from poly(4-vinylpyridine)-grafted carbon nanotube (CNT-g-P4VP) and gold nanoparticles (AuNPs) at the water/oil interface. The prepared CNT-g-P4VP/AuNPs composite nanofilms exhibited better mechanical strength and higher SERS detection sensitivity with good reproducibility, as compared to the nanofilms prepared from pure AuNPs. Also, the CNT-g-P4VP/AuNPs nanofilm can be utilized in rapid SERS detection of two antibiotics (i.e., sulfamonomethoxine and enrofloxacin). Thus, the nanofilm reported here promises great practicality as a robust, efficient, reproducible, and simple-to-fabricate SERS platform.