Multi-dimensional synergistically coupled signal enhancement on nano-micro hierarchical anemone-like substrates integrated SERS-based microfluidic sensor

We designed and prepared a novel anemone-like array substrate (ALAS) integrated pump-free microfluidic sensor based on surface-enhanced Raman spectroscopy (SERS). ALAS substrate forms ordered nanoantenna arrays on polystyrene (PS) nanospheres, which can improve the light-capturing efficiency of the substrate and induce surface plasmon resonance. It successfully achieved multi-dimensional enhancement of electric field coupling and further enhanced the Raman scattering signals of the Raman reporter molecules. Driven by a capillary pump, the seawater containing Hg2+ can be loaded in 100 seconds without the need for cumbersome syringe pumps. Our results demonstrated that the integrated sensor exhibits excellent responsiveness in detecting Hg2+ within the concentration range of 10-7 to 10-12 mol L-1. The detection limit can reach 1 pmol L-1. Therefore, we believe that this ALAS integrated microfluidic sensor provides a promising solution for the rapid and sensitive detection of Hg2+.