Fabrication of highly sensitive biomimetic SERS substrates for detection of herbicides in trace concentration

Abstract

Fabrication of facile, efficient, low cost, reproducible substrates for surface enhanced Raman scattering (SERS) based on leaf-inspired biomimetic material has been demonstrated. The naturally occurring microstructures on the surface of the plant leaves were replicated using soft lithography technique and were utilized to assemble gold nanoparticles (GNP) in order to create electromagnetic hot spots. The surface architecture of different biomimetic surfaces tends to influence the SERS performance of the substrates, which was demonstrated using methylene blue as analyte molecule. On comparison of the enhancement factors calculated from the different substrates, the effect of surface morphology of the biomimetic surface with SERS performance was correlated. Furthermore, the fabricated biomimetic SERS substrate was found to be highly efficient even for real life applications, which was demonstrated by the detection of two common herbicides, carbendazim and thiabendazole, at trace (nanomolar) concentrations.