A Serinol-Modified 1,8-Naphthalimide Fluorescent Probe for Selective Detection of H₂S in Human Serum and Hypertensive Patients.

This research involved the design, preparation, and both structural and fluorescent characterization of a novel fluorescent probe (probe 2) for H2S detection in human blood serum as well as in samples from patients with hypertension. The fluorophore 1,8-naphthalimide was selected, while an azide group served as the chemical reactive site for H2S. To increase the bioavailability of the prepared fluorescent probe, the basic 1,8-naphthalimide scaffold was modified by introducing a 2-aminopropane-1,3-diol (serinol) moiety. Fluorescence spectra were recorded to evaluate the effects of pH, time, selectivity, and H₂S concentration on fluorescence intensity. The detection limit of the target fluorescent probe was found to be 0.16 µmol L-1. Probe 2 was successfully employed for the detection of H₂S in human blood serum, with a measured concentration of 17.98 µmol L⁻¹. The accuracy of H₂S quantification was validated using the standard addition method and confirmed by UV-Vis spectrophotometry employing the methylene blue assay, whereby the concentration was found to be 17.32 µmol L⁻¹. Ultimately, probe 2 was utilized to determine H₂S levels in samples from patients with hypertension, revealing decreased concentrations relative to the concentration observed in a human serum sample as a healthy control.