Interpretation of spectra responses of metal nanoparticles to analyte based on localized surface plasmon resonance

Metal nanoparticles have potential utilities in biochemical sensing applications owing to their localized surface plasmon resonance characteristics. To facilitate the application of localized surface plasmon resonance sensors, a simple and effective interpretation of spectra responses of metal nanoparticles to analyte was developed in this paper. Based on a bilayer structure model and a trilayer structure model, a general relationship between the peak wavelength changes of extinction spectra and the thickness of the receptor layer as well as the analyte layer was established. Both analytical analysis and chloroform vapor test experiment demonstrate that the sensing performance is greatly dependent on the receptor thickness, and a thinner receptor layer will induce a greater sensitivity. These insights can be used as guidelines in fabricating highly sensitive localized surface plasmon resonance-based biochemical sensors.