Abstract: Detection of cis-jasmone (CJ) enables monitoring of growth pressure in plants, which is especially useful for sensing attacks by herbivores. Here, a sensitive and selective nanocomposite-imprinted, localized surface plasmon resonance (LSPR) sensor for CJ vapor was fabricated. Gold (Au) nano-islands were prepared by vacuum sputtering of Au nanoparticles on a glass substrate, followed by thermal annealing. Titanium molecularly imprinted sol-gels (MISGs) were spin-coated on the Au nano-islands as an adsorption layer for enhancing the selectivity of the optical sensor. Gas molecules were detected by using a small spectrometer to monitor variations in absorption spectra. In addition, the functional monomer and the ratio of matrix materials to functional monomers in the MISGs were investigated and optimized. MISGs that contained the functional monomer trimethoxyphenylsilane at a 3:1(v:v) ratio exhibited a higher sensitivity and selectivity than other films. The optical sensor would have advantages of low cost, selectivity, sensitivity, and repeatability. The limit of CJ detection in air was 3.5 ppm (signal/noise = 3). Thus, the sensor is expected to be a potential tool for CJ monitoring in agriculture applications
Author keywords: Plant volatile organic compounds, cis-Jasmone, Localized surface plasma resonance, Molecularly imprinted sol-gel, Functional monomer, Optical sensor