1：Experimental Design and Method Selection:

The study designed a multifunctional reduced graphene oxide (rGO)-based nanosheet loaded with an IDO inhibitor (IDOi) for combined PTT and immunotherapy. Methods included synthesis of rGO-FA and PEG-rGO-FA nanosheets, characterization using FTIR, Raman spectroscopy, UV-Vis-NIR absorption, AFM, and photothermal effect evaluation. In vitro and in vivo experiments assessed cellular uptake, biodistribution, photothermal toxicity, DC activation, and antitumor efficacy in a bilateral CT26 tumor mouse model.

2：Sample Selection and Data Sources:

CT26 murine colon carcinoma cell lines and female BALB/c mice (6-8 weeks old) were used. Data were obtained from at least three independent experiments.

3：List of Experimental Equipment and Materials:

Equipment included FTIR spectrometer, Raman spectrometer, UV-Vis-NIR spectrophotometer, AFM (Veeco Instruments), particle size analyzer (Brookhaven 90Plus), FLIR Ax5 camera for temperature measurement, confocal laser scanning microscopy (CLSM), flow cytometer (BD Accuri C6), Maestro imaging system (CRI, USA), HPLC system, and ELISA kits (eBiosciences). Materials included graphene oxide, folic acid, polyethylene glycol, IDOi (Epacadostat), anti-PD-L1 antibody, and various chemicals for synthesis.

4：Experimental Procedures and Operational Workflow:

Synthesis involved conjugating FA to rGO, PEG modification, IDOi loading, and characterization. In vitro studies included cellular uptake assays and photothermal toxicity tests. In vivo studies involved tumor inoculation, intravenous injection of nanosheets, NIR laser irradiation (808 nm, 1 W/cm2), biodistribution imaging, flow cytometry for immune cell analysis, and tumor growth monitoring.

5：Data Analysis Methods:

Data were analyzed using one-way ANOVA with Tukey's post-test in GraphPad Prism 5.0. Statistical significance was set at p < 0.05.