1：Experimental Design and Method Selection:

The study involved designing and synthesizing a FRET-based probe (PHS1) using coumarin and naphthalimide fluorophores to detect H2O2 and H2S. Methods included UV-Vis and fluorescence spectroscopy, cytotoxicity assays, and confocal fluorescence imaging in cells and zebrafish.

2：2S. Methods included UV-Vis and fluorescence spectroscopy, cytotoxicity assays, and confocal fluorescence imaging in cells and zebrafish. Sample Selection and Data Sources:

2. Sample Selection and Data Sources: HT-29 and HeLa cancer cell lines were used, sourced from the Food Industry Research and Development Institute (Taiwan). Zebrafish were used as live specimens, maintained under standard conditions.

3：List of Experimental Equipment and Materials:

Instruments included Shimadzu UV-1800 spectrophotometer, Bruker 400 MHz NMR spectrometer, IonSpec HiResESI mass spectrometer, RF-6000 FL spectrometer, Leica TCS SP5 X AOBS Confocal Fluorescence Microscope, and Mullikan GO microplate reader. Chemicals were procured from various commercial sources (e.g., Avra, Alfa Aesar, Sigma Aldrich).

4：Experimental Procedures and Operational Workflow:

Synthesis of PHS1 and intermediates, UV-Vis and fluorescence measurements with titrations of H2O2 and H2S, cytotoxicity assay using MTT method, cell culture and imaging for endogenous and exogenous analytes, and zebrafish imaging with probe incubation and analyte treatment.

5：Data Analysis Methods:

Fluorescence intensity changes were measured and analyzed, detection limits calculated using regression equations, and images were processed using confocal microscopy.