Abstract
A simple and sensitive method to determinate glucose content was developed based on single plasmonic nanoparticles by conventional dark-field microscopy (DFM). An enzyme-responsive plasmonic Ag/Au bilayer of rods was designed and prepared. Their localized surface plasmon resonance (LSPR) could be tailored by the enzyme reaction of glucose oxidase (GOx) by finely tuning the morphology and plasmonic optical response of the hybrid nanostructure. It was found that the plasmon resonance scattering (PRS) spectra peak (λmax) shifted to longer wavelengths under enzyme reactions, and the degree of the shift were proportional to the content of glucose. This approach is convenient to study the local concentration of glucose in real time.