1：Experimental Design and Method Selection:

The study involved designing and synthesizing two BODIPY derivatives (c1 and c2) with meso-substituted indole moieties containing NO2 and NH2 groups to investigate their photophysical properties, electrochemical behavior, and applications in cell imaging and viscosity sensing. Methods included NMR, HRMS, FTIR, UV-vis spectroscopy, fluorescence spectroscopy, cyclic voltammetry, theoretical calculations (DFT), photostability tests, pH stability tests, cytotoxicity assays, and viscosity sensitivity measurements.

2：Sample Selection and Data Sources:

Samples were synthesized from commercial chemicals including 5-nitroindole, 2,4-dimethyl-1H-pyrrole, DDQ, Et3N, 1-bromohexane, indole, and boron trifluoride diethyl etherate. Solvents used were various organic solvents and buffer solutions for different tests.

3：List of Experimental Equipment and Materials:

Equipment included Bruker VECTOR22 spectrometer for FTIR, Bruker AVANCE III 400 MHz spectrometer for NMR, Perkin Elmer Lambda 35 for UV-vis, FluoroMax Spectrofluorometer for emission spectra, Agilent 6540 high-resolution mass spectrometer for HRMS, FLS920 fluorescence spectrophotometer for quantum yield, BRUKER D8 VENTURE for X-ray diffraction, and electrochemical setup with platinum electrodes and Ag/AgCl reference. Materials included silica gel for chromatography, solvents like dichloromethane, hexane, ethanol, glycerol, and chemicals for synthesis and tests.

4：Experimental Procedures and Operational Workflow:

Synthesis involved condensation reactions, oxidation, and complexation with BF3. Characterization included spectral measurements, crystal growth, electrochemical scans, photostability under irradiation, pH titration, cell culture for imaging, and viscosity variation in solvent mixtures. Data were collected and analyzed step by step as per standard protocols.

5：Characterization included spectral measurements, crystal growth, electrochemical scans, photostability under irradiation, pH titration, cell culture for imaging, and viscosity variation in solvent mixtures. Data were collected and analyzed step by step as per standard protocols. Data Analysis Methods:

5. Data Analysis Methods: Data were analyzed using Gaussian 03 for DFT calculations, Lippert-Mataga equations for solvatochromism, Fr?ster-Hoffmann equation for viscosity dependence, and statistical methods for cytotoxicity and imaging results. Software like SHELXTL and GaussView were used for structural analysis.