Optimizing nanostructured platform for enhanced detection of photosynthetic pigments

• Optimal florescence enhancement of chlorophyll a at 10 nm thickness of aluminum oxide. • A linear response of a sensor across a wide range of chlorophyll a concentrations. • Reliable fluorescence measurements despite the inhomogeneous distribution of nanorods. Advancements in plasmonic nanotechnology have revolutionized the study of photosynthetic pigments, enabling the development of efficient artificial devices for diverse applications. In this study, we developed a nanoplatform comprising gold nanorods functionalized with promesogenic and decanethiol ligands and incorporated into Langmuir-Schaefer monolayers protected by aluminum oxide layers. The nanoplatform was further functionalized with chlorophyll a , enabling plasmonic enhancement for improved pigment detection. Our findings demonstrate a strong dependence on the spacer layer thickness, with optimal enhancement at approximately 10 nm. Notably, the system’s design supports the detection of other photosynthetic pigments with Q-band maxima shifted to wavelengths beyond 750 nm. This work provides fundamental insights into plasmon-induced effects in photosynthetic pigments and highlights the potential of this nanoplatform for applications in sensing and plasmonic-based architectures due to the wide concentration range of dye connected with a low value of its limit of detection.