Fig. 2: Characterization of the nanoparticles (NPs) and experimental evidence for their co-localization with the mitochondria.

a TEM images of the 70DSS-DDAB@PLGA/Kolliphor EL NPs (scale bar = 100 nm). b Size (blue) and zeta potential (orange) of 10DSS-DDAB@PLGA/Kolliphor EL NPs, 40DSS-DDAB@PLGA/Kolliphor EL NPs and 70DSS-DDAB@PLGA/Kolliphor EL NPs in pure water measured using DLS. Data in (b) was presented as mean values ± SD, n = 3 independent experiments. c The loading efficiency of DSS in the 10DSS-DDAB@PLGA/Kolliphor EL NPs, 40DSS-DDAB@PLGA/Kolliphor EL NPs and 70DSS-DDAB@PLGA/Kolliphor EL NPs, measured using HPLC. Data in (c) was presented as mean values ± SD, n = 3 independent experiments. d Co-localizations of the PLGA/Kolliphor EL NPs/mitochondria, as measured using CLSM, with the PLGA/Kolliphor EL NPs and mitochondria labeled with Cy5 (red) and MitoTracker Green (green), respectively. Scale bars = 10 μm. e Co-localizations of the DSS-FITC-DDAB@PLGA/Kolliphor EL NP/mitochondria, as measured using CLSM, where DSS was functionalized with FITC (green). The mitochondria were labeled with MitoTracker Deep Red (red). Scale bars = 10 μm. Dimethyldioctadecylammonium bromide (DDAB), disuccinimidyl suberate (DSS), poly (lactic-co-glycolic acid) (PLGA). Confocal images in d and e were both processed by the deconvolution method in NIS-Elements AR 5.20.00 (Nikon). Confocal image d and e from co-localization experiments are representative of biological duplicates. Source data for (a–c) are provided as a Source Data file, and source data for (b–e) also are available in the figshare repository (https://doi.org/10.6084/m9.figshare.23261618).