Metal nano-hole arrays, modulating resonances intensity and spectral position, span visible to near-infrared ranges, unlocking sensing applications. Displacing electric fields toward the interface with air, facilitated by a high-index material (SiN) substrate, refines the sensitive region and improve enhancement. Efficient and reproducible fabrication protocols, such as the modified nanosphere lithography (NSL) method, have been developed by our group for the creation of highly ordered nano-hole arrays (NHAs) in thin gold films. These arrays feature diverse properties, including thickness, hole shape, diameter, and lateral periodic or quasi-periodic spacing. Interference and coupling between plasmonic modes of different natures present a route for enhancement for SERS applications. Integrating these nanostructures within a fiber-based microfluidic system offers an innovative solution for pesticide detection. This …