【Abstract】 A novel ultrasensitive detection in a small volume of a low refractive index liquid via Surface enhanced Raman scattering(SERS)-active liquid core waveguide is described. The liquid core waveguide demonstrated was constructed by using the light-guiding silica capillary modified with SERS-active nanoparticles on the inner surface of the fiber wall. The Raman signal of the sample can be remarkably enhanced by the immobilized Ag nanoparticles. The laser and SERS scattering from the flowing liquid in the core possess the totally reflective waveguide model within the fiber wall. Thus, the sample dissolved in the low refractive index liquid, e.g. methanol, can be quantitatively monitored by Raman spectra in the liquid core cell and the detection limit can reach 10 -8 mol/L.更多还原