1：Experimental Design and Method Selection:

The probe DP5 was designed based on pentapeptide conjugated with dansyl groups using solid phase peptide synthesis (SPPS) technology. Fluorescence spectroscopy was used to detect Cu2+ and H2S through "turn-off" and "turn-on" responses, respectively. Theoretical calculations (Gaussian 09 at B3LYP/6-31G(d) level) were employed to optimize molecular structures.

2：Sample Selection and Data Sources:

Metal ions (nitrates and perchlorates), anions (sodium or potassium salts), and H2S (from NaHS) were used. Living cells (HK2 and EJ cells) were cultured in RPMI-1640 medium with 10% fetal bovine serum.

3：List of Experimental Equipment and Materials:

Instruments included Bruker Daltonics Esquire 6000 spectrometer, JNM-ECS-400 MHz NMR, pHS-3E digital pH meter, Varian UV-Cary100 spectrophotometer, Cary eclipse spectrofluorometer, LSM 710 inverted fluorescence microscope, and HPLC with Vydac C18 column. Materials included Fmoc-Rink Amide resin, Fmoc L-amino acids, dansyl chloride, solvents from Sigma Aldrich, and HEPES buffer.

4：Experimental Procedures and Operational Workflow:

DP5 synthesis via SPPS, purification by HPLC, characterization by ESI-MS and 1H NMR. Fluorescence measurements in HEPES buffer (pH 7.4) with excitation at 330 nm. Titration studies for Cu2+ and H2S, Job's plot analysis, and cell imaging with incubation steps.

5：4) with excitation at 330 nm. Titration studies for Cu2+ and H2S, Job's plot analysis, and cell imaging with incubation steps. Data Analysis Methods:

5. Data Analysis Methods: Fluorescence intensity analysis, association constant calculation, detection limit determination (3σ/k), and confocal microscopy imaging.