Templating assisted fabrication of flexible, highly stable and uniform plasmonic platform for ultrahigh enhancement of Raman and fluorescence signals: Model sensing of rhodamine-6G

Abstract

Raman-fluorescence dual enhancement offers transformative potential in fields like biosensing and bioimaging, combining exceptional sensitivity with rapid response. In this study, a novel flexible plasmonic platform, composed of silver nanocolumns (Ag-NCOLs) embedded in polydimethylsiloxane (PDMS), was investigated using 4-aminothiophenol (4-ATP) for Raman and rhodamine-6G (R6G) for fluorescence studies. This platform demonstrated remarkable enhancement factors (EFs) of ∼10¹⁴ for Raman and ∼273 for fluorescence, surpassing Ag-NCOLs on silicon (Si) by factors of 10 and 24.8, respectively. A number of control experiments confirmed the platform’s uniformity, long-term stability, and flexibility (bending and stretching). The system’s efficacy was validated through R6G detection, achieving detection limits of 0.54 nM for Raman and 0.26 nM for fluorescence. These findings establish the platform as a promising tool for diverse applications, including label-free and labeled biosensing, pathogen detection, bioimaging, in vitro diagnostics, wearable sensors, material characterization, and environmental monitoring. This work underscores the immense potential of flexible plasmonic platforms for advancing next-generation sensing and imaging technologies.