Naphthalimide-based fluorescent nanoprobes for the detection of saccharides

Three kinds of fluorescent nano probes SN-A, SN-B and SN-C, based on the photo-induced electron transfer mechanism, were synthesized for the detection of saccharides, in which small fluorescent probes with 1,8-naphthalimide as the fluorophore and phenylboronic acid as the receptor were covalently bound to SiO2 nanoparticles. The fluorescent nano particles were characterized by TEM, IR, UV-Vis and fluorescence spectra. The results showed that the particle diameter exerted a significant influence on the performance of the nanoprobes; however, the length of the linker affected the spectral response to a much lesser extent. The fluorescence intensity at 530 nm (I-530) of SN-B exhibited a good linear relationship with the fructose/sorbitol concentration and was employed in the detection of the fructose content in drinks.