4-Mercaptopyridine is a chemical compound utilized as a probe molecule in scientific research. It has been employed to investigate the performance characteristics of a composite material consisting of gold nanorods (AuNR) embedded within a polycaprolactone (PCL) fibrous mesh. By utilizing 4-Mercaptopyridine as a probe, researchers can gain insights into the interactions between the composite material and surrounding environment, as well as assess its suitability for various applications such as sensing, catalysis, or biomedical purposes. Trusted for its unique chemical properties and reactivity, 4-Mercaptopyridine plays a crucial role in advancing our understanding of nanomaterial-based systems and their potential applications in diverse fields of science and technology.