Fig. 6: Dipeptide coacervates as synthetic organelles in biological cells.

a Schematic representation of dimerized dipeptide coacervates (DDCs) as a catalytic organelle in a living cell; b Confocal imaging and DLS analysis of dimerized FF-OMe coacervates (0.25 mg mL⁻¹ in PBS buffer), scale bar: 10 μm; scale bar: 5 μm (inset); The droplets were loaded with Nile Red (NR, red) or Ru catalyst (0.5 μg mL⁻¹). 3 experiments were repeated independently with similar results; c Viability of HeLa cells after treatment with different amounts of dimerized dipeptide coacervates for 2 h, determined by MTT assay, data represent mean ± SD for n = 3 independent samples; d Confocal imaging of HeLa cells after treatment with the dimerized dipeptide coacervates (0.25 mg mL⁻¹) for 2 h, stained with Calcein-AM (green) for live cells and PI (red for dead cells, scale bar: 50 μm. 3 experiments were repeated independently with similar results; e Cellular internalization of DDCs (red) after 2 h incubation, cells were washed with cold PBS for 3 times then stained with Lysol tracker (green) and cell mask (blue), scale bar: 10 μm (middle); scale bar: 5 μm (right). 3 experiments were repeated independently with similar results; f Confocal images of HeLa cells after treatment with Ru-organelles (0.25 mg mL⁻¹) showed significantly higher emission of product (green) than controls, cell membrane was stained with cell mask (red). DDCs: dimerized dipeptide coacervates, scale bar: 20 μm; g HeLa cells incubated with Ru-organelles (0.25 mg mL⁻¹) showed significantly higher fluorescence intensity (from Rho-110 emission) compared to controls as determined by microplate reader, data represent mean ± SD for n = 3 independent samples. Error bars represent the standard deviation (n = 3) from microplate reader analysis.