Metal–organic frameworks modified electrode for H2S detections in biological and pharmaceutical agents

The development of hydrogen sulfide (H₂S) sensors is essential to address H₂S-related pharmacology since slow-releasing H₂S medications have been identified to be prospective options for cancer treatments. Here, we described an electrochemical sensor for highly selective and sensitive detection of aqueous H₂S, using a thin film of fumarate-based face-centered cubic (fcu)-based metal–organic frameworks (fum-fcu-MOF) modified on laser-scribed graphene (LSGE). The fum-fcu-MOF has shown a strong affinity and chemical stability to H₂S analysis. The electrochemical and H₂S catalytic properties were studied for fum-fcu-MOF/LSGE. An amperometry and differential pulse voltammetry techniques were demonstrated to validate the sensor. The resulting sensor delivered acceptable analytical parameters in terms of; detection limit (3.0 µM), dynamic range (10–500 µM), reproducibility, and stability (94.7%). The sensor's practical validity was demonstrated in bacterial cells and H₂S-releasing drug, where the sensor was able to monitor the continuous release of in-situ H₂S. The pharmacokinetics of a slow releasing H₂S donor is accessed at different time intervals and different concentration levels. Our research indicate that this fum-fcu-MOF based H₂S sensor holds potential in understanding pharmacokinetics of H₂S releasing drugs.