Figure 3.

Optical and fluorescence images of the nanoporous nanoparticles (NPNPs) after incubation with 2 fluorescent polymers of different molecular weights (MWs): dextran-FITC 14 kDa (panels A and B), and dextran-FITC 6 kDa (panels C and D). The adsorption of the lighter polymer is clearly indicated by the green fluorescence emitted from the nanoparticles (panel D). In contrast, no green fluorescence can be observed being emitted from the heavier polymer (the blue fluorescence comes from salt residues), confirming the MW cut-off.