Fig. 4

a DiD nuclei distribution in HeLa cells. The cells were assessed after 4 and 8 h of incubation with the DiD@mP and DiD@cPRP nanoparticles and monitored by CLSM and mean fluorescence intensity. Scale bar: 25 μm. b DiD penetration in HeLa MCSs after 4 h of incubation with the DiD@mP and DiD@cPRP nanoparticles, as monitored by CLSM and mean fluorescence intensity. Scale bar: 100 μm. Data are shown as mean ± SD (n = 3) (*P < 0.05, **P < 0.01, and ***P < 0.001)