Surface functionalization of mesoporous silica nanoparticles with pyronine derivative for selective detection of hydrogen sulfide in aqueous solution

Abstract

The selective detection of hydrogen sulfide (H2S) in aqueous solution has drawn increasing attention over the past decade. Although many fluorescent chemosensors in homogeneous solutions have been developed, the creation of rapid, highly sensitive and selective fluorescent nanoparticle sensors for detection of H2S are still less reported. In the present work, a novel organic-inorganic composite fluorescent sensor, M-SiO2@PYR, was synthesized by covalent coupling pyronine (PYR) on the solid surface of mesoporous silica nanoparticles. The obtained mesoporous nanoparticles were characterized by TEM and BET measurements. The chemical immobilization of organic fluorophores on the silica nanoparticles were analyzed by FT-IR, XPS, TGA, and solid state NMR methods. The fluorescent mesoporous nanoparticle sensor, M-SiO2@PYR, was found to show sensitive and selective quenching responses toward H2S in aqueous solution compared to a series of competitive analytes. The nanoparticle sensor also displayed a low detection limit of 103.6 nM to H2S, illustrating a high sensitivity. Moreover, the detection of H2S could be also realized in biological fluids like serum or urine. The present work provides a novel way to prepare fluorescent sensor for detecting biothiols in aqueous solution, which may be further used to develop discriminative sensor for multiple biothiols by modulating surface modification.