Silica Nanoparticle-Based FRET System for Hydrogen Sulfide Detection in Biological and Food Samples

Hydrogen sulfide (H2S), a crucial endogenous gasotransmitter, plays a significant role in monitoring pathological and physiological processes as well as in the realm of food safety control. The detection of H2S poses numerous challenges due to the complexity of biological fluids and food samples and the high demands for biocompatible probe molecules. To address these challenges, we have developed an innovative silica nanoparticle-based Förster resonance energy transfer (FRET) system with pyrene (Py) and pyronine (Pyr) embedded as energy donors and acceptors (Pyr@Py-SiO2 NPs). This system not only enhances the biocompatibility of fluorescent probes but also effectively mitigates interference from complex samples in the detection of endogenous H2S through its dual-mode FRET response. Our study reveals that pyrene and pyronine units embedded within the silica nanoparticles facilitate efficient energy transfer, enabling both colorimetric and ratiometric dual-mode optical detection of H2S. This approach is highly sensitive (detection limit of 71.5 nM), rapid (response time of ≤10 s), and uninfluenced by common anions and biological thiols. Moreover, we have successfully applied this system to the detection of H2S in various practical scenarios, including human urine, onion slices, and food spoilage. This work provides an effective and practical method for monitoring H2S in complex biological systems and real-world food samples.