Fig. 2
Interaction of rbNPs with culture cells. (A) Cell number is measured by CCK-8 assay after 24 h incubation with rbNPs or PS-Lip at varying concentrations. Colon26, B16-BL6, HeLa, MDCK, HaCaT and RAW264.7 cells are incubated with 0.1−10 × 109 rbNPs or PS-Lip/mL. Results are expressed as the mean ± SD of three samples. #p < 0.01 vs. no treatment (NT) group. (B) Confocal microscopic images of colon26 cells after the addition of DiI-labeled rbNPs (DiI-rbNPs). Colon26 cells are incubated with 0.1−10 × 109 DiI-rbNPs/mL for 1, 3, and 12 h. Scale bars indicate 50 μm. White arrows indicate DiI-rbNPs. (C) Cellular uptake of DiO-labeled rbNPs (DiO-rbNPs) in colon26 cells. Colon26 cells are incubated with DiO-rbNPs for 3, 6, 12, and 24 h at 37 °C, then fixed with paraformaldehyde. The fluorescence intensity of colon26 cells is quantified by flow cytometry, and the mean fluorescence intensity (MFI) is calculated. Results are expressed as the mean ± SD of three samples. #p < 0.01 vs. NT group. Colon26, murine colon adenocarcinoma cell line; B16-BL6, murine melanoma cell line; HeLa, human cervix adenocarcinoma cell line; MDCK, canine kidney cell line; HaCaT, human keratinocyte cell line; and RAW264.7, murine macrophage cell line